JP2008268374A

JP2008268374A - Fixing device and image forming apparatus

Info

Publication number: JP2008268374A
Application number: JP2007108592A
Authority: JP
Inventors: Masahiro Ishino; 正浩石野
Original assignee: Fuji Xerox Co Ltd
Current assignee: Fujifilm Business Innovation Corp
Priority date: 2007-04-17
Filing date: 2007-04-17
Publication date: 2008-11-06

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing device capable of preventing fixing failures, such as wrinkles and irregularities in an image. <P>SOLUTION: Regarding the fixing device 10, a fixing belt 13 is stretched to be laid between a heat roll 11 and a peeling roll, and a nip part N is formed by the fixing belt 13 and a pressure mechanism 20. The pressure mechanism 20 is configured to press a pressure belt 21 against the fixing belt 13 through the use of a pressure pad 30 comprising a hard pad 31 and a soft pad 32. The pressure surface 31c of the hard pad 31, that forms the exit part of the nip part N, is substantially parallel to the straight path part 13a of the fixing belt 13 that travels from the nip part N to the peeling roll, and the pressure surface 31c forms an angle 31e together with the front surface 31d of the hard pad 31. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、電子写真方式を利用した画像形成装置に用いられる定着装置および画像形成装置に関する。 The present invention relates to a fixing device and an image forming apparatus used in an image forming apparatus using an electrophotographic system.

近年のデジタル化・高精細化などの改善によって、カラーの画像形成装置で高画質な画像が得られるようになってきている。この高画質化に伴い、電子写真方式を利用したカラー画像形成装置を印刷市場や写真市場に展開しようという試みがなされている。このような試みに対応するための技術が、例えば特許文献１に開示されている。特許文献１には、画像形成部、第一定着装置及び第二定着装置を備えている画像形成装置が開示されている。この画像形成装置では、第一定着装置により一次定着を行った後に第二定着装置により二次定着を行うことで、高光沢度の画像出力が可能になる。 Due to recent improvements such as digitalization and high definition, a color image forming apparatus can obtain high-quality images. Along with this improvement in image quality, attempts have been made to develop color image forming apparatuses using an electrophotographic system in the printing market and the photographic market. For example, Patent Document 1 discloses a technique for dealing with such an attempt. Patent Document 1 discloses an image forming apparatus including an image forming unit, a first fixing device, and a second fixing device. In this image forming apparatus, high-gloss image output is possible by performing primary fixing with the first fixing device and then secondary fixing with the second fixing device.

また、電子写真方式の画像形成装置に用いられる定着装置として、特許文献２乃至３に開示のごとき構成のものが知られている。
特許文献２には、円筒状芯金に耐熱性弾性体層が形成され、さらにその表面に耐熱性樹脂層が被覆された加熱定着ローラと、エンドレスベルトと、エンドレスベルト内側に配置された圧力部材と、を具備した定着装置であって、エンドレスベルトを加熱定着ローラに所定角度巻き付けて、エンドレスベルトと加熱定着ローラとの間に記録シートが通過させられるニップ部を形成し、該ニップ部において、圧力部材をエンドレスベルトを介して加熱定着ローラに押圧させることにより、加熱定着ローラの耐熱性弾性体層に歪みを生じさせる定着装置が開示されている。
特許文献３には、定着対象の記録シートを無端ベルトに当接させた状態で冷却手段により冷却してから剥離する方式の定着装置において、加熱ロールから剥離用ロールに向かう無端ベルト及びそのベルトに当接した状態で搬送される定着対象の記録シートを均一にかつ安定して冷却し、冷却ムラのない良好な定着を可能にする定着装置が開示されている。 In addition, as a fixing device used in an electrophotographic image forming apparatus, those having configurations as disclosed in Patent Documents 2 to 3 are known.
In Patent Document 2, a heat-fixing roller having a heat-resistant elastic body layer formed on a cylindrical metal core and a heat-resistant resin layer coated on the surface thereof, an endless belt, and a pressure member disposed inside the endless belt The endless belt is wound around the heat fixing roller at a predetermined angle to form a nip portion through which the recording sheet can pass between the endless belt and the heat fixing roller. A fixing device is disclosed in which a pressure member is pressed against a heat-fixing roller via an endless belt to cause distortion in the heat-resistant elastic layer of the heat-fixing roller.
In Patent Document 3, in a fixing device in which a recording sheet to be fixed is brought into contact with an endless belt and then cooled by a cooling unit and then peeled, an endless belt heading from a heating roll to a peeling roll and the belt are disclosed. There has been disclosed a fixing device that uniformly and stably cools a recording sheet to be fixed conveyed in a contact state, and enables good fixing without uneven cooling.

特開２００４−１０９９０５号公報JP 2004-109905 A 特開平１１−１３３７７６号公報Japanese Patent Application Laid-Open No. 11-133776 特開２００２−９９１６８号公報JP 2002-99168 A

ところで、定着装置では、定着作用中や排出中に記録媒体が接している部材と相対移動してシワや画像の乱れ等の定着不具合を生ずることのない構成が望まれる。
本発明は、シワや画像乱れ等の定着不具合を防ぐことのできる定着装置等を提供することを目的とする。 By the way, it is desired that the fixing device has a configuration that does not cause a fixing defect such as wrinkles or image distortion due to relative movement with a member in contact with the recording medium during the fixing operation or discharging.
An object of the present invention is to provide a fixing device or the like that can prevent fixing problems such as wrinkles and image distortion.

かかる目的のもと、本発明の定着装置は、周回可能に設けられた定着ベルト部材と、前記定着ベルト部材を加熱する加熱手段と、前記定着ベルト部材との間に記録媒体を挟んで加圧する加圧域を形成する加圧部材と、前記定着ベルト部材の前記加圧域より移動方向下流側で当該定着ベルト部材から前記記録媒体を剥離する剥離部と、を備え、前記加圧部材は、前記加圧域の出口部分で前記定着ベルト部材に前記記録媒体を押圧し当該加圧域から前記剥離部に向かう当該定着ベルト部材の移動経路と略平行な押圧面を有し、当該押圧面は当該加圧部材の出口側の端面と角を成していることを特徴とする。 For this purpose, the fixing device of the present invention presses the fixing belt member provided in a rotatable manner, a heating means for heating the fixing belt member, and a recording medium between the fixing belt member. A pressure member that forms a pressure area; and a peeling portion that peels the recording medium from the fixing belt member on the downstream side in the movement direction from the pressure area of the fixing belt member. The pressing surface has a pressing surface that is substantially parallel to a moving path of the fixing belt member that presses the recording medium against the fixing belt member at the outlet portion of the pressing region and travels from the pressing region toward the peeling portion. It is characterized in that it forms a corner with the end face on the outlet side of the pressure member.

ここで、上記構成に加えて、前記加圧部材の周囲を周回可能に設けられ、当該加圧部材によって前記定着ベルト部材に押圧されて当該定着ベルト部材との間に前記加圧域を形成する加圧ベルト部材をさらに備えることを特徴とすることができる。
また、前記加圧域から前記剥離部に至る前記定着ベルト部材に付着した前記記録媒体を冷却する冷却手段をさらに備えることを特徴とすることができる。
また、前記冷却手段は、前記加圧域から前記剥離部に至る間の前記定着ベルト部材の周回移動経路の内側に配設されて、当該定着ベルト部材を冷却すると共に当該定着ベルト部材の移動経路を規定する冷却部材を備え、前記冷却部材によって規定される前記定着ベルト部材の移動経路は、前記加圧域の出口における当該定着ベルト部材の移動経路と同一平面または同一平面より前記記録媒体の画像形成面側に設定されていることを特徴とすることができる。
また、前記定着ベルト部材が掛け回され回転する定着ロール部材をさらに備え、前記加圧部材は、前記定着ロール部材の前記定着ベルト部材が掛け回した部位を加圧しており、前記冷却部材によって規定される前記定着ベルト部材の移動経路は、前記加圧部材の加圧によって前記定着ロール部材が最も変形した位置の前記加圧域の出口における当該定着ベルト部材の移動経路と同一平面または同一平面より前記記録媒体の画像形成面側に設定されていることを特徴とすることができる。 Here, in addition to the above configuration, the pressure member is provided so as to be able to circulate, and is pressed against the fixing belt member by the pressure member to form the pressure region between the fixing belt member and the fixing belt member. A pressure belt member may be further provided.
The image forming apparatus may further include a cooling unit that cools the recording medium attached to the fixing belt member from the pressurizing region to the peeling portion.
In addition, the cooling means is disposed inside a circulation movement path of the fixing belt member between the pressure region and the peeling portion, and cools the fixing belt member and moves the fixing belt member. And a moving path of the fixing belt member defined by the cooling member is the same plane as the moving path of the fixing belt member at the outlet of the pressurizing zone or an image of the recording medium from the same plane. It can be characterized in that it is set on the formation surface side.
Further, the image forming apparatus further includes a fixing roll member that is wound around and rotated by the fixing belt member, and the pressure member pressurizes a portion of the fixing roll member around which the fixing belt member is wound, and is defined by the cooling member. The moving path of the fixing belt member is the same plane or the same plane as the moving path of the fixing belt member at the outlet of the pressurizing zone at the position where the fixing roll member is most deformed by the pressurization of the pressurizing member. It is characterized in that it is set on the image forming surface side of the recording medium.

他の視点で捉えた本発明の定着装置は、加熱されて移動する定着ベルト部材を加圧部材で加圧して加圧域を形成し、当該加圧域を記録媒体が通過する際に当該記録媒体上のトナー像を当該定着ベルト部材の熱で溶融させて当該記録媒体に圧着させる溶融圧着部と、前記溶融圧着部で前記トナー像が溶融圧着されて前記定着ベルト部材に付着した前記記録媒体を当該定着ベルト部材から剥離させる剥離部と、を備え、前記定着ベルト部材は、前記加圧域の出口で前記記録媒体側に屈曲せずに前記溶融圧着部から前記剥離部に当該記録媒体を搬送するように構成されていることを特徴とする。 The fixing device of the present invention viewed from another viewpoint forms a pressure area by pressing a heated and moving fixing belt member with a pressure member, and the recording medium passes through the pressure area when the recording medium passes through the pressure area. A melt-bonding portion that melts the toner image on the medium with the heat of the fixing belt member and presses the toner image on the recording medium; and the recording medium that the toner image is melt-pressed and adhered to the fixing belt member at the melt-pressing portion. A peeling portion that peels the recording medium from the fixing belt member, and the fixing belt member does not bend toward the recording medium at the outlet of the pressurizing region, and the recording medium is transferred from the melt-bonding portion to the peeling portion. It is comprised so that it may convey.

本発明の画像形成装置は、トナー像を形成するトナー像形成手段と、前記トナー像形成手段によって形成されたトナー像を記録媒体上に転写する転写手段と、前記記録媒体上に転写されたトナー像を当該記録媒体上に定着する定着装置と、を備え、前記定着装置は、周回可能に設けられた定着ベルト部材と、前記定着ベルト部材を加熱する加熱手段と、前記定着ベルト部材との間に前記記録媒体を挟んで加圧する加圧域を形成する加圧部材と、前記定着ベルト部材の前記加圧域より移動方向下流側で当該定着ベルト部材から前記記録媒体を剥離する剥離部と、を備え、前記加圧部材は、前記加圧域の出口部分で前記定着ベルト部材に前記記録媒体を押圧し当該加圧域から前記剥離部に向かう当該定着ベルト部材の移動経路と略平行な押圧面を有し、当該押圧面は当該加圧部材の出口側の端面と角を成していることを特徴とする。 The image forming apparatus of the present invention includes a toner image forming unit that forms a toner image, a transfer unit that transfers a toner image formed by the toner image forming unit onto a recording medium, and a toner that is transferred onto the recording medium. A fixing device that fixes an image on the recording medium, and the fixing device is provided between a fixing belt member that is rotatively provided, a heating unit that heats the fixing belt member, and the fixing belt member. A pressurizing member that forms a pressurizing region that pressurizes the recording medium, and a peeling unit that peels the recording medium from the fixing belt member on the downstream side of the pressurizing region of the fixing belt member in the moving direction; The pressing member presses the recording medium against the fixing belt member at an outlet portion of the pressing area, and presses substantially parallel to a moving path of the fixing belt member from the pressing area toward the peeling portion. Face And, the pressing surface is characterized in that it forms an end surface and corners of the outlet side of the pressure member.

請求項１の定着装置によれば、本発明を適用しない場合と比べて、シワや画像乱れ等の定着不具合の発生を抑えることができる。
請求項２によれば、本発明を適用しない場合と比べて、小型の構成で広い加圧域幅を得ることができる。
請求項３によれば、本発明を適用しない場合と比べて、記録媒体を迅速に冷却して冷却効率を高めることができる。
請求項４によれば、本発明を適用しない場合と比べて、加圧域の出口で生ずる画像乱れの発生を抑えることができる。
請求項５によれば、本発明を適用しない場合と比べて、定着ロール部材の軸方向全域で画像不良の発生を抑えることができる。
請求項６の定着装置によれば、本発明を適用しない場合と比べて、シワや画像乱れ等の定着不具合の発生を抑えることができる。
請求項７の画像形成装置によれば、本発明を適用しない場合と比べて、シワや画像乱れ等の定着不具合の発生を抑え、高品質な画像出力が可能となる。 According to the fixing device of the first aspect, it is possible to suppress the occurrence of fixing problems such as wrinkles and image distortion as compared with the case where the present invention is not applied.
According to the second aspect, compared with the case where the present invention is not applied, a wide pressure range width can be obtained with a small configuration.
According to the third aspect, compared with the case where the present invention is not applied, the recording medium can be rapidly cooled to increase the cooling efficiency.
According to the fourth aspect, compared to the case where the present invention is not applied, it is possible to suppress the occurrence of image disturbance that occurs at the outlet of the pressurization region.
According to the fifth aspect, compared to the case where the present invention is not applied, it is possible to suppress the occurrence of image defects in the entire axial direction of the fixing roll member.
According to the fixing device of the sixth aspect, it is possible to suppress the occurrence of fixing problems such as wrinkles and image disturbance as compared with the case where the present invention is not applied.
According to the image forming apparatus of the seventh aspect, compared with the case where the present invention is not applied, it is possible to suppress the occurrence of fixing problems such as wrinkles and image disturbance and to output a high quality image.

以下、添付図面を参照して、本発明を実施するための最良の形態(以下、実施の形態)の一構成例について詳細に説明する。
図１は本実施の形態に係る定着装置１０の全体構成を示す縦断面図、図２はその要部拡大図である。
定着装置１０は、定着ロール部材および加熱手段である加熱ロール１１と、剥離ロール１２と、加熱ロール１１と剥離ロール１２とに張架された定着ベルト１３とを備えている。
また、定着装置１０は、定着ベルト１３の周回経路に囲まれた空間内の加熱ロール１１と剥離ロール１２との間に設けられた冷却手段および冷却部材としての冷却装置１４と、定着ベルト１３を挟んで加熱ロール１１に対向して配置された加圧機構２０とを備えている。 Hereinafter, an exemplary configuration of the best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the accompanying drawings.
FIG. 1 is a longitudinal sectional view showing an overall configuration of a fixing device 10 according to the present embodiment, and FIG. 2 is an enlarged view of a main part thereof.
The fixing device 10 includes a heating roll 11 that is a fixing roll member and a heating unit, a peeling roll 12, and a fixing belt 13 stretched between the heating roll 11 and the peeling roll 12.
Further, the fixing device 10 includes a cooling device 14 as a cooling means and a cooling member provided between the heating roll 11 and the peeling roll 12 in a space surrounded by the circulation path of the fixing belt 13, and the fixing belt 13. And a pressurizing mechanism 20 disposed opposite to the heating roll 11.

加熱ロール１１は回転して定着ベルト１３を図中矢印で示す方向に周回駆動するようになっており、加圧機構２０は定着ベルト１３の加熱ロール１１を巻回した部位に圧接して加圧域および溶融圧着部としてのニップ部Ｎを形成している。
そして、定着装置１０は、表面にトナー像が形成された記録媒体としての記録用紙Ｐを、ニップ部Ｎで加圧・加熱し、定着ベルト１３の移動によって搬送しつつ冷却装置１４で冷却し、定着ベルト１３が剥離ロール１２を巻回した部位で定着ベルト１３から剥離して排出する。
すなわち、加熱ロール１１と定着ベルト１３と加圧機構２０とで溶融圧着部を構成し、剥離ロール１２が剥離部を構成しているものである。 The heating roll 11 rotates to drive the fixing belt 13 in the direction indicated by the arrow in the drawing, and the pressure mechanism 20 presses against the portion of the fixing belt 13 around which the heating roll 11 is wound. A nip portion N as a zone and a melt-bonded portion is formed.
Then, the fixing device 10 pressurizes and heats the recording paper P as a recording medium having a toner image formed on the surface thereof at the nip portion N, cools it with the cooling device 14 while being conveyed by the movement of the fixing belt 13, The fixing belt 13 is peeled off from the fixing belt 13 at a portion where the peeling roll 12 is wound and discharged.
That is, the heating roll 11, the fixing belt 13, and the pressure mechanism 20 constitute a melt-bonding part, and the peeling roll 12 constitutes a peeling part.

以下、各部の構成を詳細に説明する。
加熱ロール１１は、所定の径且つ肉厚の円筒状のコア１１ａの周囲に耐熱性の弾性層１１ｂが形成されたロールである。コア１１ａは、例えばアルミニウム、ＳＵＳ（ステンレス合金鋼）等の金属材料にて形成されている。弾性層１１ｂは、所定の弾性を有するたとえばシリコーンゴムまたはフッ素ゴム等により所定の厚さに形成されている。この加熱ロール１１は、図示しない支持フレームに回転自在に設けられている。また、加熱ロール１１は図示しないモータ等の駆動手段と連繋しており、駆動手段によって所定の周速度で回転駆動されるようになっている。
加熱ロール１１の内部には、加熱部材として、例えば定格６００Ｗのハロゲンヒータ１７が配設されている。このハロゲンヒータ１７により、加熱ロール１１が所定の表面温度に加熱されるようになっている。 Hereinafter, the configuration of each unit will be described in detail.
The heating roll 11 is a roll in which a heat-resistant elastic layer 11b is formed around a cylindrical core 11a having a predetermined diameter and thickness. The core 11a is formed of a metal material such as aluminum or SUS (stainless alloy steel). The elastic layer 11b is formed to have a predetermined thickness with, for example, silicone rubber or fluorine rubber having predetermined elasticity. The heating roll 11 is rotatably provided on a support frame (not shown). Further, the heating roll 11 is connected to driving means such as a motor (not shown), and is driven to rotate at a predetermined peripheral speed by the driving means.
Inside the heating roll 11, for example, a halogen heater 17 having a rating of 600 W is disposed as a heating member. The halogen roller 17 heats the heating roll 11 to a predetermined surface temperature.

剥離ロール１２は、所定の径且つ肉厚の円筒状のロールであって、例えばアルミニウム、ＳＵＳ（ステンレス合金鋼）等の金属材料にて形成され、図示しない支持フレームに回転自在に設けられている。
また、剥離ロール１２は、図示しないバネ等からなる公知の張力付与機構によって加熱ロール１１と離間する側に所定の力で付勢されており、加熱ロール１１との間に張架された定着ベルト１３に所定の張力を付与するようになっている。
さらに、剥離ロール１２の表面には、温度センサ１８が接触して配置されている。この温度センサ１８は、剥離ロール１２の表面温度を検出するためのものである。 The peeling roll 12 is a cylindrical roll having a predetermined diameter and thickness, and is formed of a metal material such as aluminum or SUS (stainless alloy steel), and is rotatably provided on a support frame (not shown). .
Further, the peeling roll 12 is urged with a predetermined force toward the side away from the heating roll 11 by a known tension applying mechanism including a spring or the like (not shown), and the fixing belt stretched between the heating roll 11. A predetermined tension is applied to 13.
Further, a temperature sensor 18 is disposed in contact with the surface of the peeling roll 12. The temperature sensor 18 is for detecting the surface temperature of the peeling roll 12.

定着ベルト１３は、ベルト基材の外面側に弾性離型層が形成されて成る所定幅で継ぎ目なしの無端状のベルトである。ベルト基材は、たとえばポリイミド、ポリアミド等の耐熱性樹脂やニッケル、アルミニウム等の金属材料によって厚さが３０〜２００μｍ程度に形成され、また、弾性離型層は、たとえばシリコーン系ゴム、フッ素系ゴム等によって１０〜２００μｍ程度の厚さに形成されている。なお、この定着ベルト１３の外周面（弾性離型層の表面）は、できる限り平滑面（鏡面に近いもの）であることが望ましい。 The fixing belt 13 is an endless belt having a predetermined width and having no seam formed by forming an elastic release layer on the outer surface side of the belt base material. The belt base material is formed to a thickness of about 30 to 200 μm using a heat-resistant resin such as polyimide or polyamide, or a metal material such as nickel or aluminum, and the elastic release layer is formed of, for example, silicone rubber or fluorine rubber. The thickness is about 10 to 200 μm. The outer peripheral surface of the fixing belt 13 (the surface of the elastic release layer) is preferably as smooth as possible (as close to a mirror surface) as possible.

このような定着ベルト１３は、加熱ロール１１と剥離ロール１２との間に、所定長さの直線状の直線経路部１３ａを有する周回経路で張架されており、加熱ロール１１の回転によって周回駆動されるようになっている。
定着ベルト１３が加熱ロール１１を掛け回した部位には、後述する加圧機構２０によってニップ部Ｎが形成されている。また、定着ベルト１３が剥離ロール１２を掛け回す部位は、前述のごとく剥離部を構成しており、その剥離ロール１２の周面に沿った屈曲（曲率の変化）によって定着ベルト１３から記録用紙Ｐを剥離する。 Such a fixing belt 13 is stretched between a heating roll 11 and a peeling roll 12 by a circulation path having a linear straight path portion 13 a having a predetermined length, and is driven by rotation of the heating roll 11. It has come to be.
A nip portion N is formed at a portion where the fixing belt 13 is wound around the heating roll 11 by a pressurizing mechanism 20 described later. Further, as described above, the part where the fixing belt 13 wraps around the peeling roll 12 constitutes a peeling portion, and the recording paper P is removed from the fixing belt 13 by bending (change in curvature) along the peripheral surface of the peeling roll 12. To peel off.

さらに、加熱ロール１１から剥離ロール１２に至る定着ベルト１３（直線経路部１３ａ）の外側（図１中下側）には、用紙ガイド２３が配置されている。
用紙ガイド２３は、定着ベルト１３の直線経路部１３ａに沿って延設されており、これによって、定着ベルト１３に密着した状態の記録用紙Ｐは、定着ベルト１３と用紙ガイド２３との間を搬送されるようになっている。
また、加熱ロール１１の図１中上側に、加熱ロール１１を掛け回す定着ベルト１３に近接して、定着ベルト１３の表面温度を検出する温度センサ２５が配置されている。この温度センサ２５による検知情報（定着ベルト１３の温度情報）は図示しない制御装置に入力され、制御装置がこの温度情報に基づいて定着ベルト１３の温度制御を行うようになっている。 Further, a paper guide 23 is disposed on the outer side (lower side in FIG. 1) of the fixing belt 13 (straight path portion 13a) from the heating roll 11 to the peeling roll 12.
The paper guide 23 is extended along the linear path portion 13 a of the fixing belt 13, so that the recording paper P in close contact with the fixing belt 13 is conveyed between the fixing belt 13 and the paper guide 23. It has come to be.
In addition, a temperature sensor 25 that detects the surface temperature of the fixing belt 13 is disposed on the upper side of the heating roll 11 in FIG. Information detected by the temperature sensor 25 (temperature information of the fixing belt 13) is input to a control device (not shown), and the control device controls the temperature of the fixing belt 13 based on the temperature information.

冷却装置１４は、基板部１４ａの上面に複数の放熱フィン１４ｂが立設されて、アルミニウム合金等の熱伝導の良い素材によって形成されている。このような冷却装置１４は、定着ベルト１３の直線経路部１３ａの内側に、放熱フィン１４ｂの延設方向を定着ベルト１３の幅方向とし、基板部１４ａの外面が定着ベルト１３に熱伝導可能に接触するように配設されている。なお、図示しないが、放熱フィン１４ｂに向けて送風して放熱を促進する放熱ファン等を備えて構成しても良い。 The cooling device 14 includes a plurality of heat radiation fins 14b standing on the upper surface of the substrate portion 14a, and is formed of a material having good heat conductivity such as an aluminum alloy. In such a cooling device 14, the extending direction of the radiating fins 14 b is set in the width direction of the fixing belt 13 inside the linear path portion 13 a of the fixing belt 13, and the outer surface of the substrate portion 14 a can conduct heat to the fixing belt 13. It arrange | positions so that it may contact. In addition, although not shown in figure, you may comprise and comprise the radiation fan etc. which ventilate toward the radiation fin 14b and accelerate heat dissipation.

加圧機構２０は、加圧ベルト部材としての加圧ベルト２１と、加圧ベルト２１の内側に設けられた押圧ガイド２２とにより構成されている。そして、押圧ガイド２２が、加圧ベルト２１を定着ベルト１３の加熱ロール１１を掛け回した部位に押圧して、加熱ロール１１の弾性層１１ｂを所定量弾性変形させてニップ部Ｎを形成している。 The pressure mechanism 20 includes a pressure belt 21 as a pressure belt member and a pressure guide 22 provided inside the pressure belt 21. Then, the pressing guide 22 presses the pressure belt 21 against the portion of the fixing belt 13 around which the heating roll 11 is wound, and the elastic layer 11b of the heating roll 11 is elastically deformed by a predetermined amount to form the nip portion N. Yes.

加圧ベルト２１は、ベルト基材の表面に離型層が形成されて成る継ぎ目がない無端状のベルトであり、定着ベルト１３と対応する幅に形成されている。ベルト基材はたとえばポリイミド、ポリアミド等の耐熱性樹脂によって厚さ１５〜１２５μｍ程度に形成され、離型層はたとえばフッ系耐熱樹脂等によって厚さ５〜２０μｍに形成されている。
このような加圧ベルト２１は、押圧ガイド２２に外挿され、この押圧ガイド２２によって回動自在に支持されている。その左右方向（定着装置１０の幅方向）の位置は、加圧ベルト２１の両端部に配置された図示しないベルト規制部材によって規定されるようになっている。
そして、加圧ベルト２１は、ニップ部Ｎで圧接する定着ベルト１３の周回移動に従動して、押圧ガイド２２の周囲を回動するようになっている。 The pressure belt 21 is a seamless endless belt formed by forming a release layer on the surface of the belt base material, and is formed in a width corresponding to the fixing belt 13. The belt base material is formed to a thickness of about 15 to 125 μm by a heat resistant resin such as polyimide or polyamide, and the release layer is formed to a thickness of 5 to 20 μm by a fluorine heat resistant resin or the like.
Such a pressure belt 21 is extrapolated to the pressing guide 22 and is rotatably supported by the pressing guide 22. The position in the left-right direction (the width direction of the fixing device 10) is defined by belt regulating members (not shown) disposed at both ends of the pressure belt 21.
The pressure belt 21 is rotated around the pressing guide 22 in accordance with the circumferential movement of the fixing belt 13 pressed in contact with the nip portion N.

押圧ガイド２２は、支持ガイド２２ａによって、加圧部材としての圧力パッド３０と、摺動補助シート２２ｂと、潤滑剤含浸部材２２ｃとを支持して構成され、全体として加圧ベルト２１が余裕を有して外挿される略円形の断面形状を呈している。その長さは加熱ロール１１と対応している。そして、押圧ガイド２２は、前述のごとく加圧ベルト２１の内側に配置され、加圧ベルト２１の回動を案内すると共に、圧力パッド３０で加圧ベルト２１を加熱ロール１１側に押圧付勢してニップ部Ｎを形成するようになっている。 The pressure guide 22 is configured to support a pressure pad 30 as a pressure member, a sliding assist sheet 22b, and a lubricant impregnated member 22c by a support guide 22a, and the pressure belt 21 as a whole has a margin. Thus, it has a substantially circular cross-sectional shape to be extrapolated. The length corresponds to the heating roll 11. The pressure guide 22 is arranged inside the pressure belt 21 as described above, guides the rotation of the pressure belt 21, and presses the pressure belt 21 toward the heating roll 11 with the pressure pad 30. Thus, a nip portion N is formed.

支持ガイド２２ａは、外形が略円形の中空のパイプ状で、合成樹脂または金属等によって所定の剛性を有して形成されている。その上側に圧力パッド３０が、下側に潤滑剤含浸部材２２ｃがそれぞれ装着されている。 The support guide 22a is a hollow pipe having a substantially circular outer shape, and is formed with a predetermined rigidity using a synthetic resin, metal, or the like. The pressure pad 30 is mounted on the upper side, and the lubricant-impregnated member 22c is mounted on the lower side.

圧力パッド３０は、ハードパッド３１とソフトパッド３２とから構成されている。
ハードパッド３１は、平板状の装着板部３１ａの一方の端に所定幅で所定高さの押圧部３１ｂが立設された断面形状略Ｌ字状で、耐熱性を有する所定の硬度の素材によって形成されている。押圧部３１ｂの上面は、平坦な押圧面３１ｃとなっている。
ソフトパッド３２は、耐熱性を有する弾性素材、たとえば所定硬度のシリコーンゴムやフッ素ゴム等によって所定の厚さに形成され、ハードパッド３１の装着板部３１ａの上に設けられている。このソフトパッド３２は、その硬度がハードパッド３１より相対的に低く、また、その上面の幅はハードパッド３１の押圧面３１ｃより大きく設定されている。 The pressure pad 30 includes a hard pad 31 and a soft pad 32.
The hard pad 31 has a substantially L-shaped cross-section in which a pressing portion 31b having a predetermined width and a predetermined height is erected on one end of a flat mounting plate portion 31a, and is made of a heat-resistant material having a predetermined hardness. Is formed. The upper surface of the pressing portion 31b is a flat pressing surface 31c.
The soft pad 32 is formed with a predetermined thickness from a heat-resistant elastic material such as silicone rubber or fluoro rubber having a predetermined hardness, and is provided on the mounting plate portion 31 a of the hard pad 31. The soft pad 32 is relatively lower in hardness than the hard pad 31, and its upper surface width is set larger than the pressing surface 31 c of the hard pad 31.

このようにハードパッド３１とソフトパッド３２とから構成された圧力パッド３０は、全体として見ると、その上面が硬度の異なる二種類の面を有している。そして、ソフトパッド３２が配設された側を定着ベルト１３の移動方向上流側として支持ガイド２２ａの上部に設けられ、その上面全体で加圧ベルト２１を加熱ロール１１の側に押圧し、加圧ベルト２１と定着ベルト１３との間に略平面状のニップ部Ｎを形成している。 Thus, the pressure pad 30 composed of the hard pad 31 and the soft pad 32 has two types of surfaces with different upper surfaces when viewed as a whole. The side on which the soft pad 32 is disposed is provided on the upper side of the support guide 22a as the upstream side in the moving direction of the fixing belt 13, and the entire upper surface thereof is pressed against the heating roll 11 to press the pressure belt 21. A substantially planar nip portion N is formed between the belt 21 and the fixing belt 13.

このような圧力パッド３０によって形成されたニップ部Ｎは、ソフトパッド３２によって形成される部位は圧接力が弱く、ハードパッド３１によって形成される部位は相対的に圧接力が強い。すなわち、ニップ部Ｎの入口側（定着ベルト１３の移動方向上流側）では圧接力が弱く、出口側（下流側）では圧接力が強い。これにより、ソフトパッド３２でトナー像を溶融させるのに必要な通過時間を得るニップ幅を確保すると共に、ハードパッド３１が出口側の部位で局所的に高い圧力で圧接させてトナー像の表面を平滑化して画像光沢を付与するようになっている。
なお、この圧力パッド３０およびニップ部Ｎの形状等については後に詳述する。 In the nip portion N formed by such a pressure pad 30, a portion formed by the soft pad 32 has a weak pressure contact force, and a portion formed by the hard pad 31 has a relatively strong pressure contact force. That is, the pressure contact force is weak on the inlet side of the nip portion N (upstream side in the movement direction of the fixing belt 13), and the pressure contact force is strong on the outlet side (downstream side). As a result, a nip width for obtaining a passing time necessary for melting the toner image with the soft pad 32 is ensured, and the hard pad 31 is brought into pressure contact with a locally high pressure at a portion on the outlet side so that the surface of the toner image is formed. It smoothes to give image gloss.
The shapes of the pressure pad 30 and the nip portion N will be described in detail later.

摺動補助シート２２ｂは、耐熱性を有する低摩擦の素材、たとえばフッ素樹脂等によって形成された所定厚さのシートであって、圧力パッド３０の上面全体を覆うように設けられている。これにより、摺動補助シート２２ｂは、圧力パッド３０と加圧ベルト２１の間に介在し、加圧ベルト２１の摺動抵抗を軽減させるように作用する。 The sliding assist sheet 22b is a sheet having a predetermined thickness formed of a heat-resistant low-friction material such as a fluororesin, and is provided so as to cover the entire upper surface of the pressure pad 30. Thus, the sliding assist sheet 22b is interposed between the pressure pad 30 and the pressure belt 21 and acts to reduce the sliding resistance of the pressure belt 21.

潤滑剤含浸部材２２ｃは、フェルト等の素材にシリコーンオイル等の潤滑剤を含浸させたものであり、支持ガイド２２ａの下部に加圧ベルト２１の幅方向全域に亘って、加圧ベルト２１の内周面に接触するように配置されている。これにより、加圧ベルト２１の内周面に潤滑剤を塗布し、加圧ベルト２１と摺動補助シート２２ｂとの摺動抵抗の低減と、加圧ベルト２１の内周面や摺動補助シート２２ｂ表面の摩耗を抑制する。 The lubricant-impregnated member 22c is obtained by impregnating a material such as felt with a lubricant such as silicone oil. The lubricant-impregnated member 22c is formed in the lower portion of the support guide 22a over the entire width direction of the pressure belt 21. It arrange | positions so that a surrounding surface may be contacted. Thereby, the lubricant is applied to the inner peripheral surface of the pressure belt 21, the sliding resistance between the pressure belt 21 and the sliding assist sheet 22b is reduced, and the inner peripheral surface of the pressure belt 21 and the sliding assist sheet are reduced. 22b suppresses surface wear.

上記のごとく構成された定着装置１０は下記のごとく作用する。
定着作用時には、加熱ロール１１は、ハロゲンヒータ１７の通電によって加熱され、同時に回転駆動される。これによって、定着ベルト１３が所定の定着温度に加熱されると共に周回駆動され、さらに、ニップ部Ｎで定着ベルト１３に圧接する加圧機構２０の加圧ベルト２１も、定着ベルト１３に従動して周回する。 The fixing device 10 configured as described above operates as follows.
During the fixing operation, the heating roll 11 is heated by energization of the halogen heater 17 and is simultaneously driven to rotate. As a result, the fixing belt 13 is heated to a predetermined fixing temperature and is driven to rotate, and the pressure belt 21 of the pressure mechanism 20 that presses against the fixing belt 13 at the nip portion N is also driven by the fixing belt 13. Go around.

そして、ニップ部Ｎに、未定着のトナー像が形成された記録用紙Ｐを挟み、加熱・加圧してトナー像を記録用紙Ｐに定着させ、冷却装置１４で冷却して排出する。
すなわち、記録用紙Ｐがニップ部Ｎを通過する際、記録用紙Ｐ上のトナー像は、ニップ部Ｎで作用する圧力と定着ベルト１３を介して供給される熱とによって溶融して記録用紙Ｐ内に埋め込まれる。その記録用紙Ｐは、ニップ部Ｎを通過した後も溶融トナーの接着力で定着ベルト１３の外周面に密着した状態を保ち、定着ベルト１３と共に直線経路部１３ａを移動する。記録用紙Ｐは直線経路部１３ａを移動中に冷却装置１４によって定着ベルト１３を介して冷却され、トナーが固化する。その後、定着ベルト１３と共に移動する記録用紙Ｐは、定着ベルト１３が剥離ロール１２を掛け回す部位（剥離部）で、自身の剛性（いわゆる腰）によって定着ベルト１３から剥離する。 Then, the recording paper P on which an unfixed toner image is formed is sandwiched in the nip portion N, heated and pressurized to fix the toner image on the recording paper P, cooled by the cooling device 14, and discharged.
That is, when the recording paper P passes through the nip portion N, the toner image on the recording paper P is melted by the pressure acting on the nip portion N and the heat supplied via the fixing belt 13 to be recorded in the recording paper P. Embedded in. Even after the recording paper P passes through the nip portion N, the recording paper P is kept in close contact with the outer peripheral surface of the fixing belt 13 by the adhesive force of the molten toner, and moves along the linear path portion 13 a together with the fixing belt 13. The recording paper P is cooled by the cooling device 14 via the fixing belt 13 while moving along the linear path portion 13a, and the toner is solidified. Thereafter, the recording paper P moving together with the fixing belt 13 is peeled off from the fixing belt 13 by its own rigidity (so-called waist) at a portion (peeling portion) where the fixing belt 13 is wound around the peeling roll 12.

ここで、本定着装置１０によって定着作用するのに適する記録用紙Ｐについて説明する。
図３は、記録用紙Ｐを説明するための概略断面図である。図３に示すように、記録用紙Ｐは、基材Ｐ１に熱可塑性樹脂を主成分とする透明樹脂Ｐ２を積層形成したものが使用される。この基材Ｐ１としては、画像形成用の普通紙、コート紙や、印画紙等が挙げられる。透明樹脂Ｐ２の層を構成する熱可塑性樹脂としては、ポリエチレン樹脂、スチレン−アクリル酸エステル樹脂等が挙げられる。また、透明樹脂Ｐ２の層は、定着時の加熱加圧により溶融してトナー像が埋め込まれる程度の層厚さからなるものであることが好ましい。なお、記録用紙Ｐは、画像形成装置に適用可能である記録媒体であれば特に制約されるものではないが、この定着装置１０により光沢性に富む写真調の画像を得る観点から、図３に示す記録用紙Ｐを用いるのが好ましい。 Here, the recording paper P suitable for fixing by the fixing device 10 will be described.
FIG. 3 is a schematic cross-sectional view for explaining the recording paper P. As shown in FIG. 3, as the recording paper P, a substrate P1 is used in which a transparent resin P2 mainly composed of a thermoplastic resin is laminated. Examples of the base material P1 include plain paper for image formation, coated paper, and photographic paper. Examples of the thermoplastic resin constituting the layer of the transparent resin P2 include a polyethylene resin and a styrene-acrylate resin. Further, the layer of the transparent resin P2 preferably has a layer thickness that is melted by heat and pressure at the time of fixing to embed the toner image. The recording paper P is not particularly limited as long as it is a recording medium that can be applied to the image forming apparatus. From the viewpoint of obtaining a glossy photographic image by the fixing device 10, FIG. It is preferable to use the recording paper P shown.

つぎに、本発明に特徴的な構成である圧力パッド３０およびニップ部Ｎの形状等について、前述の図１および図２と、図４および図５を用いて詳細に説明する。
図４（ａ）は圧力パッド３０の拡大断面図である。また、図５はニップ部Ｎを記録用紙Ｐの出口側から見た概念図である。
圧力パッド３０は、前述のごとくハードパッド３１とソフトパッド３２とから構成されている。
ハードパッド３１は、装着板部３１ａの端に押圧部３１ｂが立設されており、装着板部３１ａの上にソフトパッド３２を支持する。 Next, the shape and the like of the pressure pad 30 and the nip portion N, which are characteristic features of the present invention, will be described in detail with reference to FIGS. 1 and 2 and FIGS. 4 and 5 described above.
FIG. 4A is an enlarged cross-sectional view of the pressure pad 30. FIG. 5 is a conceptual view of the nip portion N as viewed from the exit side of the recording paper P.
The pressure pad 30 is composed of the hard pad 31 and the soft pad 32 as described above.
The hard pad 31 has a pressing portion 31b erected at the end of the mounting plate portion 31a, and supports the soft pad 32 on the mounting plate portion 31a.

ここで、ハードパッド３１の押圧部３１ｂの上面（押圧面３１ｃ）は、図４（ａ）に示すように略平面状で、この押圧面３１ｃと押圧部３１ｂの出口側（定着ベルト１３および記録用紙Ｐの移動方向下流側）の端面である前面３１ｄとは、角３１ｅを成すように形成されている。
角３１ｅは、直角より小さい鋭角で、鋭利に形成されることが望ましい。本実施の形態では、直角（９０度）で、面取りは０．５ｍｍ以下に形成されている。 Here, the upper surface (pressing surface 31c) of the pressing portion 31b of the hard pad 31 is substantially flat as shown in FIG. 4 (a), and the pressing surface 31c and the outlet side of the pressing portion 31b (the fixing belt 13 and the recording). The front surface 31d, which is the end surface on the downstream side in the movement direction of the paper P, is formed to form a corner 31e.
The corner 31e is preferably an acute angle smaller than a right angle and sharply formed. In the present embodiment, the chamfer is formed at a right angle (90 degrees) and 0.5 mm or less.

そして、圧力パッド３０は、そのハードパッド３１の押圧面３１ｃを、加熱ロール１１から剥離ロール１２に至る定着ベルト１３の移動経路である直線経路部１３ａと略平行として配設され、摺動補助シート２２ｂを介して定着ベルト１３を加圧ベルト２１に押圧してニップ部Ｎを形成している。これにより、押圧面３１ｃの押圧によって形成されるニップ部Ｎの出口部分は平面状となり、このニップ部Ｎの出口部分と直線経路部１３ａとは同一平面で（屈曲することなく）連続するようになっている。 The pressure pad 30 is disposed so that the pressing surface 31c of the hard pad 31 is substantially parallel to the linear path portion 13a that is the moving path of the fixing belt 13 from the heating roll 11 to the peeling roll 12, and the sliding assist sheet. A nip portion N is formed by pressing the fixing belt 13 against the pressure belt 21 through 22b. As a result, the exit portion of the nip portion N formed by the pressing of the pressing surface 31c has a flat shape, and the exit portion of the nip portion N and the straight path portion 13a are continuous on the same plane (without bending). It has become.

また、冷却装置１４によって規定される定着ベルト１３の直線経路部１３ａは、圧力パッド３０のハードパッド３１の押圧面３１ｃと同一面か又は記録用紙Ｐのトナー像が形成される面側（図中上側）となるように設定される。なお、図は、同一面に設定されている。
すなわち、冷却装置１４は、基板部１４ａの外面が定着ベルト１３から熱伝導可能とするため、必然的に直線経路部１３ａにおいて定着ベルト１３に圧接するように設けられる。このため、見方を換えると、直線経路部１３ａは冷却装置１４によって規定されていることになる。その冷却装置１４によって規定される直線経路部１３ａを、前述の条件を満たすように設定するものである。 Further, the linear path portion 13a of the fixing belt 13 defined by the cooling device 14 is the same surface as the pressing surface 31c of the hard pad 31 of the pressure pad 30 or the surface side on which the toner image of the recording paper P is formed (in the drawing). (Upper side). The figures are set on the same plane.
That is, the cooling device 14 is inevitably provided in pressure contact with the fixing belt 13 in the linear path portion 13a so that the outer surface of the substrate portion 14a can conduct heat from the fixing belt 13. For this reason, in other words, the linear path portion 13 a is defined by the cooling device 14. The straight path portion 13a defined by the cooling device 14 is set so as to satisfy the above-described conditions.

さらに、より詳細には、ハードパッド３１の押圧面３１ｃと、冷却装置１４によって規定される直線経路部１３ａとの相対的な位置関係は、加熱ロール１１の軸方向の変形を考慮して定められる。
すなわち、加熱ロール１１は、加圧機構２０（圧力パッド３０）によって加えられる圧力によって、その軸方向中央部が加圧機構２０とは反対の側（図中上側）に撓む（変形する）。これによって、ハードパッド３１の押圧面３１ｃの位置も変位し、押圧面３１ｃと冷却装置１４によって規定される直線経路部１３ａの相対位置関係も変わる。このため、このような撓みによる位置関係の変化を考慮し、最も撓みの大きな部位（図５中Ｃ．Ｌ．で示す加熱ロール１１の軸方向中央）におけるハードパッド３１の押圧面３１ｃの位置に対して、冷却装置１４によって規定される直線経路部１３ａの位置が、同一面か又は記録用紙Ｐのトナー像が形成される面側（図中上側）となるように設定するものである。 More specifically, the relative positional relationship between the pressing surface 31 c of the hard pad 31 and the linear path portion 13 a defined by the cooling device 14 is determined in consideration of the axial deformation of the heating roll 11. .
That is, the heating roll 11 bends (deforms) the axial center portion thereof on the side opposite to the pressurizing mechanism 20 (upper side in the drawing) by the pressure applied by the pressurizing mechanism 20 (pressure pad 30). As a result, the position of the pressing surface 31c of the hard pad 31 is also displaced, and the relative positional relationship between the pressing surface 31c and the linear path portion 13a defined by the cooling device 14 is also changed. For this reason, in consideration of the change in the positional relationship due to such bending, the position of the pressing surface 31c of the hard pad 31 at the most bent portion (the center in the axial direction of the heating roll 11 indicated by CL in FIG. 5). On the other hand, the position of the linear path portion 13a defined by the cooling device 14 is set so as to be on the same surface or the surface side (upper side in the figure) on which the toner image of the recording paper P is formed.

上記のごとく構成された圧力パッド３０およびニップ部Ｎの構造によれば、ニップ部Ｎの出口において、記録用紙Ｐが定着ベルト１３から剥離したり、記録用紙Ｐにシワが寄るといった不具合を防ぐことができる。
すなわち、たとえば、図４（ｂ）および（ｃ）に示す圧力パッド３０′および圧力パッド３０″のように、ハードパッド３１′，３１″の押圧面３１ｃの前方側の縁（角３１ｅ′，３１ｅ″）に円弧状や４５度の面取りが施され、さらに、この角３１ｅ′，３１ｅ″に沿うように（角３１ｅ′，３１ｅ″によって移動経路が屈曲するように）定着ベルト１３の移動経路が設定されている場合には、定着ベルト１３に付着した記録用紙Ｐが角３１ｅ′，３１ｅ″でしごかれて丸まり、ニップ部Ｎの出口において、定着ベルト１３から記録用紙Ｐが剥離したり、記録用紙Ｐにシワがよるといった不具合が生じ得る。これらの不具合は、特に、図４（ｂ）に一例としての封筒ＰＥを概念的に示すように、二枚重ねの一方の面に画像形成する場合に生じやすい。 According to the structure of the pressure pad 30 and the nip portion N configured as described above, it is possible to prevent problems such as the recording paper P peeling off from the fixing belt 13 or wrinkles on the recording paper P at the exit of the nip portion N. Can do.
That is, for example, like the pressure pad 30 ′ and the pressure pad 30 ″ shown in FIGS. 4B and 4C, the front edge of the pressing surface 31c of the hard pads 31 ′ and 31 ″ (corners 31e ′ and 31e). ″) Is arcuate or chamfered at 45 degrees, and the movement path of the fixing belt 13 is further along the corners 31e ′ and 31e ″ (the movement path is bent by the corners 31e ′ and 31e ″). When set, the recording paper P adhering to the fixing belt 13 is squeezed and curled at the corners 31e ′ and 31e ″, and the recording paper P is peeled off from the fixing belt 13 at the exit of the nip portion N. There may be a problem that the recording paper P is wrinkled. These problems are particularly likely to occur when an image is formed on one surface of a double stack, as conceptually shown in FIG. 4B as an example of an envelope PE.

本構成では、圧力パッド３０のハードパッド３１の押圧面３１ｃと前面３１ｄとが角３１ｅを成すと共に、ニップ部Ｎと定着ベルト１３の移動経路（直線経路部１３ａ）とが同一平面で連続するように設定されているため、記録用紙Ｐをしごくように作用することが無く、封筒等、二枚重ねの一方の面に画像形成する場合でも、シワを生じさせることなく高光沢で高品質な定着が可能となるものである。 In this configuration, the pressing surface 31c of the hard pad 31 and the front surface 31d of the pressure pad 30 form a corner 31e, and the nip portion N and the moving path (straight path portion 13a) of the fixing belt 13 are continuous on the same plane. Therefore, even if an image is formed on one side of an overlapping sheet such as an envelope, high-gloss and high-quality fixing is possible without causing wrinkles. It will be.

つぎに、上記のごとき定着装置１０が適用される画像形成装置について説明する。
図６は、定着装置１０が適用される画像形成装置１００の構成を説明するブロック図である。
上述した本実施の形態に係る定着装置１０は、複写機、プリンタ、ファクシミリ、これらの複合機等の電子写真方式を用いた画像形成装置１００に適用することができる。図６に示す画像形成装置１００は、トナー像を形成するトナー像形成手段１１０と、トナー像形成手段１１０によって形成されたトナー像を記録用紙Ｐ上に転写する転写手段１２０と、記録用紙Ｐ上に転写されたトナー像を当該記録用紙Ｐに定着する定着手段１３０と、転写手段１２０に記録用紙Ｐを所定のタイミングで供給する用紙供給手段１４０とを含むものである。そして、この定着手段１３０として、上述した本実施の形態に係る定着装置１０を用いることができる。なお、定着装置１０以外の構成は、従来公知のいずれの構成であっても、本発明の目的に反しない限り用いることができる。また、トナー像形成手段１１０としては、静電潜像保持体上に静電潜像を形成する静電潜像形成部と、当該静電潜像をトナーにより現像する現像部と、で構成される。 Next, an image forming apparatus to which the fixing device 10 as described above is applied will be described.
FIG. 6 is a block diagram illustrating the configuration of the image forming apparatus 100 to which the fixing device 10 is applied.
The fixing device 10 according to the above-described embodiment can be applied to an image forming apparatus 100 using an electrophotographic system such as a copying machine, a printer, a facsimile machine, or a multifunction machine of these. An image forming apparatus 100 shown in FIG. 6 includes a toner image forming unit 110 that forms a toner image, a transfer unit 120 that transfers the toner image formed by the toner image forming unit 110 onto the recording paper P, and a recording paper P The image forming apparatus includes a fixing unit 130 that fixes the toner image transferred onto the recording sheet P, and a sheet supply unit 140 that supplies the recording sheet P to the transfer unit 120 at a predetermined timing. As the fixing unit 130, the above-described fixing device 10 according to the present embodiment can be used. Note that any configuration other than the fixing device 10 can be used as long as it is not contrary to the object of the present invention. The toner image forming unit 110 includes an electrostatic latent image forming unit that forms an electrostatic latent image on the electrostatic latent image holding member, and a developing unit that develops the electrostatic latent image with toner. The

なお、上記実施の形態以外の他の実施の形態も採用可能である。たとえば、冷却装置１４の構成などは、適宜変更可能である。 It should be noted that other embodiments other than the above-described embodiment can be employed. For example, the configuration of the cooling device 14 can be changed as appropriate.

本実施の形態に係る定着装置の縦断面図である。1 is a longitudinal sectional view of a fixing device according to an exemplary embodiment. 定着装置の要部拡大図である。FIG. 記録用紙を説明するための概略断面図である。It is a schematic sectional drawing for demonstrating a recording paper. 圧力パッドの拡大断面図である。It is an expanded sectional view of a pressure pad. ニップ部を記録用紙の出口側から見た概念図である。FIG. 4 is a conceptual diagram of a nip portion as viewed from the exit side of a recording sheet. 定着装置が適用される画像形成装置の構成を説明するブロック図である。1 is a block diagram illustrating a configuration of an image forming apparatus to which a fixing device is applied.

Explanation of symbols

１０…定着装置、１１…加熱ロール（加熱手段、定着ロール部材）、１２…剥離ロール（剥離部）、１３…定着ベルト（定着ベルト部材）、１３ａ…直線経路部（定着ベルトの移動経路）、１４…冷却装置（冷却手段，冷却部材）、１７…ハロゲンヒータ（加熱部材）、２０…加圧機構、２１…加圧ベルト（加圧ベルト部材）、３０…圧力パッド（加圧部材）、３１ｃ…押圧面、３１ｄ…前面（加圧部材の出口側の端面）、３１ｅ…角、１００…画像形成装置、１１０…トナー像形成手段、１２０…転写手段、Ｎ…ニップ部（加圧域、溶融圧着部）、Ｐ…記録用紙（記録媒体） DESCRIPTION OF SYMBOLS 10 ... Fixing apparatus, 11 ... Heating roll (heating means, fixing roll member), 12 ... Peeling roll (peeling part), 13 ... Fixing belt (fixing belt member), 13a ... Linear path | route part (movement path | route of a fixing belt), DESCRIPTION OF SYMBOLS 14 ... Cooling device (cooling means, cooling member), 17 ... Halogen heater (heating member), 20 ... Pressure mechanism, 21 ... Pressure belt (pressure belt member), 30 ... Pressure pad (pressure member), 31c ... Pressing surface, 31d ... Front face (end face on the outlet side of the pressure member), 31e ... Square, 100 ... Image forming apparatus, 110 ... Toner image forming means, 120 ... Transfer means, N ... Nip part (Pressure area, melting) Crimp part), P ... Recording paper (recording medium)

Claims

A fixing belt member provided so as to be capable of rotating,
Heating means for heating the fixing belt member;
A pressurizing member that forms a pressurizing region for pressurizing the recording medium with the fixing belt member interposed therebetween;
A peeling portion for peeling the recording medium from the fixing belt member on the downstream side in the moving direction from the pressure area of the fixing belt member;
With
The pressing member has a pressing surface that is substantially parallel to a moving path of the fixing belt member that presses the recording medium against the fixing belt member at an outlet portion of the pressing area and moves from the pressing area toward the peeling portion. The pressing surface forms an angle with the end surface on the outlet side of the pressing member.

A pressure belt member provided around the pressure member so as to be able to circulate and being pressed against the fixing belt member by the pressure member to form the pressure area between the pressure belt member and the fixing belt member; The fixing device according to claim 1.

The fixing device according to claim 1, further comprising a cooling unit that cools the recording medium attached to the fixing belt member extending from the pressurizing region to the peeling portion.

The cooling means is disposed inside a circumferential movement path of the fixing belt member between the pressure area and the peeling portion, and cools the fixing belt member and defines a movement path of the fixing belt member. A cooling member for
The moving path of the fixing belt member defined by the cooling member is set on the image forming surface side of the recording medium from the same plane or the same plane as the moving path of the fixing belt member at the outlet of the pressurizing area. The fixing device according to claim 3.

A fixing roll member that is wound around and rotated by the fixing belt member;
The pressure member pressurizes a portion of the fixing roll member around which the fixing belt member is wound,
The movement path of the fixing belt member defined by the cooling member is the same as the movement path of the fixing belt member at the outlet of the pressure area at the position where the fixing roll member is most deformed by the pressure of the pressure member. The fixing device according to claim 4, wherein the fixing device is set on the image forming surface side of the recording medium from a plane or the same plane.

The fixing belt member that is heated and moved is pressed by a pressure member to form a pressure area, and when the recording medium passes through the pressure area, the toner image on the recording medium is heated by the heat of the fixing belt member. A melt-bonded portion that is melted and pressure-bonded to the recording medium;
A peeling part for peeling off the recording medium attached to the fixing belt member after the toner image has been melted and pressure-bonded at the fusion pressing part;
With
The fixing belt member is configured to convey the recording medium from the melt-bonding portion to the peeling portion without being bent toward the recording medium at the outlet of the pressurizing region. .

Toner image forming means for forming a toner image;
Transfer means for transferring the toner image formed by the toner image forming means onto a recording medium;
A fixing device for fixing the toner image transferred onto the recording medium onto the recording medium,
The fixing device includes:
A fixing belt member provided so as to be capable of rotating,
Heating means for heating the fixing belt member;
A pressurizing member that forms a pressurizing region for pressurizing the recording medium between the fixing belt member;
A peeling portion for peeling the recording medium from the fixing belt member on the downstream side in the moving direction from the pressure area of the fixing belt member;
With
The pressing member has a pressing surface that is substantially parallel to a moving path of the fixing belt member that presses the recording medium against the fixing belt member at an outlet portion of the pressing area and moves from the pressing area toward the peeling portion. The pressing surface forms an angle with the end surface on the outlet side of the pressing member.