JP2019012144A

JP2019012144A - Fixation device

Info

Publication number: JP2019012144A
Application number: JP2017128002A
Authority: JP
Inventors: 遼森原; Ryo Morihara; 鈴見　雅彦; Masahiko Suzumi; 雅彦鈴見; 秋月　智雄; Tomoo Akizuki; 智雄秋月; 達也衣川; Tatsuya Kinugawa; 丈晴仲田; Takeharu Nakada; 金森　昭人; Akito Kanamori; 昭人金森; 中園　祐輔; Yusuke Nakazono; 祐輔中園; 伸二久保; Shinji Kubo
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 2017-06-29
Filing date: 2017-06-29
Publication date: 2019-01-24
Anticipated expiration: 2037-06-29
Also published as: JP6995509B2

Abstract

【課題】ヒータに接触している熱伝導部材を安定的にフィルムに接触させることが可能な構成を有する定着装置を提供する。
【解決手段】回転可能な筒状のフィルムと、第１の面と、前記第１の面と反対側の第２の面を有する板状のヒータであって、前記第１の面で前記フィルムの内面に接触する長細い板状のヒータと、前記ヒータの長手方向に長く、前記ヒータの前記第２の面に接触している熱伝導部材と、
を有し、前記フィルムを介した前記ヒータの熱でトナー画像を加熱し前記トナー画像を記録材に定着する定着装置において、前記熱伝導部材は、前記フィルムの回転方向における前記ヒータの上流側端部よりも外側で前記ヒータの前記第２の面から前記第１の面に向かう方向に延びる延長部を有し、前記延長部は、前記ヒータの前記第１の面から前記フィルム側に突出し前記フィルムと接触することを特徴とする。
【選択図】図１４PROBLEM TO BE SOLVED: To provide a fixing device having a configuration capable of stably contacting a heat conducting member in contact with a heater with a film.
A plate-like heater having a rotatable cylindrical film, a first surface, and a second surface opposite to the first surface, wherein the film is formed on the first surface. A long thin plate-shaped heater that contacts the inner surface of the heater, a heat conducting member that is long in the longitudinal direction of the heater and is in contact with the second surface of the heater,
A fixing device that heats a toner image with heat of the heater via the film and fixes the toner image on a recording material, wherein the heat conducting member is an upstream end of the heater in the rotation direction of the film. An extension portion extending in a direction from the second surface of the heater toward the first surface outside the portion, the extension portion projecting from the first surface of the heater toward the film side, and It is in contact with a film.
[Selection] FIG.

Description

本発明は、電子写真方式の複写機・レーザープリンタ等の画像形成装置に用いられる定着装置に関するものである。 The present invention relates to a fixing device used in an image forming apparatus such as an electrophotographic copying machine or a laser printer.

電子写真方式の画像形成装置で用いられる定着装置として、次の構成が知られている。筒状のフィルムと、フィルムに接触するヒータと、フィルムを介してヒータと共にニップ部を形成する加圧ローラと、を有する構成である。未定着トナー画像を担持する記録材は、このニップ部で搬送されつつ加熱され、トナー画像が記録材に定着される。 The following configuration is known as a fixing device used in an electrophotographic image forming apparatus. It is the structure which has a cylindrical film, the heater which contacts a film, and the pressurization roller which forms a nip part with a heater through a film. The recording material carrying the unfixed toner image is heated while being conveyed at the nip portion, and the toner image is fixed on the recording material.

ところで、高速プリントに対応させるために定着装置のフィルムを高速回転させると、ヒータからフィルムへの熱供給が間に合わなくなる場合がある。そこで、特許文献１には、ヒータのフィルムと接触する面以外からもヒータからフィルムに熱伝達を行うことができる構成が開示されている。具体的な構成としては、ヒータのフィルムと接触する面と反対側の面に熱伝導部材（金属板）を接触させ、その熱伝導部材をフィルムに接触させる構成である。この構成により、より高速で定着処理することが可能になる。 By the way, if the film of the fixing device is rotated at high speed in order to cope with high-speed printing, the heat supply from the heater to the film may not be in time. In view of this, Patent Document 1 discloses a configuration in which heat can be transferred from the heater to the film other than the surface that contacts the heater film. As a specific configuration, a heat conduction member (metal plate) is brought into contact with a surface of the heater opposite to the surface in contact with the film, and the heat conduction member is brought into contact with the film. With this configuration, the fixing process can be performed at a higher speed.

特開２００３−２５７５９２JP 2003-257592 A

ヒータに接触している熱伝導部材を安定的にフィルムに接触させて、熱伝導部材を介してヒータの熱をフィルムに供給することが可能な定着装置を提供する。 Provided is a fixing device capable of stably bringing a heat conducting member in contact with a heater into contact with a film and supplying heat of the heater to the film through the heat conducting member.

上記課題を解決するための本発明の側面は、回転可能な筒状のフィルムと、第１の面と、前記第１の面と反対側の第２の面を有する板状のヒータであって、前記第１の面で前記フィルムの内面に接触する長細い板状のヒータと、前記ヒータの長手方向に長く、前記ヒータの前記第２の面に接触している熱伝導部材と、を有し、前記フィルムを介した前記ヒータの熱でトナー画像を加熱し前記トナー画像を記録材に定着する定着装置において、前記熱伝導部材は、前記フィルムの回転方向における前記ヒータの上流側端部よりも外側で前記ヒータの前記第２の面から前記第１の面に向かう方向に延びる延長部を有し、前記延長部は、前記ヒータの前記第１の面から前記フィルムの側に突出し前記フィルムと接触することを特徴とする。 A side surface of the present invention for solving the above problems is a plate-shaped heater having a rotatable cylindrical film, a first surface, and a second surface opposite to the first surface. A long and thin plate-like heater that contacts the inner surface of the film on the first surface, and a heat conduction member that is long in the longitudinal direction of the heater and that contacts the second surface of the heater. In the fixing device that heats the toner image with the heat of the heater through the film and fixes the toner image on the recording material, the heat conducting member is from an upstream end of the heater in the rotation direction of the film. An extension portion extending in a direction from the second surface of the heater toward the first surface on the outer side, and the extension portion protrudes from the first surface of the heater toward the film side, and the film It is characterized by contacting with.

ヒータに接触した熱伝導部材を安定的にフィルムに接触させて、熱伝導部材を介してヒータの熱をフィルムに供給することができる。 The heat conducting member in contact with the heater can be stably brought into contact with the film, and the heat of the heater can be supplied to the film through the heat conducting member.

実施例１に係る画像形成装置の概略断面図。1 is a schematic cross-sectional view of an image forming apparatus according to Embodiment 1. FIG. 実施例１に係る定着装置の概略断面図。1 is a schematic cross-sectional view of a fixing device according to Embodiment 1. FIG. 実施例１に係る熱伝導部材とヒータとの位置関係を示す概略断面図。FIG. 2 is a schematic cross-sectional view illustrating a positional relationship between a heat conducting member and a heater according to the first embodiment. 実施例１の変形例１に係る熱伝導部材とヒータとの位置関係を示す概略断面図。FIG. 6 is a schematic cross-sectional view showing a positional relationship between a heat conducting member and a heater according to Modification 1 of Example 1. 実施例１の変形例２に係る熱伝導部材とヒータとの位置関係を示す概略断面図。FIG. 6 is a schematic cross-sectional view showing a positional relationship between a heat conducting member and a heater according to a second modification of the first embodiment. （ａ）（ｂ）実施例１に係る定着フィルムの回転軌道と、熱伝導部材と、の位置関係を示す概略断面図。（ｃ）実施例２に係る定着フィルムの回転軌道と、熱伝導部材と、の位置関係を示す概略断面図。(A) (b) The schematic sectional drawing which shows the positional relationship of the rotation track | orbit of the fixing film which concerns on Example 1, and a heat conductive member. (C) The schematic sectional drawing which shows the positional relationship of the rotation track | orbit of the fixing film which concerns on Example 2, and a heat conductive member. 実施例２の変形例１に係るヒータホルダの規制部と、熱伝導部材と、ヒータと、の位置関係を示す概略断面図である。FIG. 10 is a schematic cross-sectional view showing a positional relationship among a restricting portion of a heater holder, a heat conducting member, and a heater according to Modification 1 of Example 2. 実施例２の変形例２に係るヒータホルダの規制部と、熱伝導部材と、ヒータと、の位置関係を示す概略断面図である。It is a schematic sectional drawing which shows the positional relationship of the control part of the heater holder which concerns on the modification 2 of Example 2, a heat conductive member, and a heater. 実施例３に係る定着フィルム回転軌道と、熱伝導部材と、ヒータと、の位置関係を示す概略断面図である。FIG. 6 is a schematic cross-sectional view illustrating a positional relationship among a fixing film rotation track, a heat conduction member, and a heater according to Example 3. 実施例３の変形例１に係る熱伝導部材とヒータの概略断面図。FIG. 6 is a schematic cross-sectional view of a heat conducting member and a heater according to Modification 1 of Example 3. 実施例３の変形例２に係る熱伝導部材とヒータの概略断面図。FIG. 6 is a schematic cross-sectional view of a heat conducting member and a heater according to a second modification of the third embodiment. 実施例４における定着フィルムユニットの構成を示した斜視図。FIG. 6 is a perspective view showing a configuration of a fixing film unit in Example 4. 実施例４における定着フィルムユニットの長手端部の拡大図。FIG. 6 is an enlarged view of a longitudinal end portion of a fixing film unit in Example 4. 実施例４における定着フィルムユニットの長手端部の断面図。FIG. 6 is a cross-sectional view of a longitudinal end portion of a fixing film unit in Example 4. 実施例４の変形例におけるフィルムユニットの長手端部の拡大図。The enlarged view of the longitudinal end part of the film unit in the modification of Example 4. FIG. 実施例４の変形例おけるフィルムユニットの長手端部の断面図。Sectional drawing of the longitudinal end part of the film unit in the modification of Example 4. FIG.

〔実施例１〕
本発明の第１の実施例に係る定着装置について図面を参照しながら以下に説明する。最初に本実施例における画像形成装置の全体構成を説明し、次いで、定着装置について説明する。 [Example 1]
A fixing device according to a first embodiment of the present invention will be described below with reference to the drawings. First, the overall configuration of the image forming apparatus in this embodiment will be described, and then the fixing device will be described.

（画像形成装置本体）
本実施例において、記録材上に未定着トナー像を形成する方法及び画像形成装置の一例を図１に示す概略図を用いて説明する。本実施例における画像形成装置５０は、感光ドラム上のトナー像を直接記録材Ｐ上に転写する電子写真方式の画像形成装置である。像担持体である感光ドラム１の周面には、回転方向（矢印Ｒ１方向）に沿って順に、帯電器２、レーザー光Ｌを感光ドラム１に照射する露光装置３、現像器５、転写ローラ１０、及び感光ドラムクリーナー１６が配置されている。まず、感光ドラム１は、その表面が帯電器２によってマイナス極性に帯電される。次に帯電された感光ドラム１は、露光手段３のレーザー光Ｌにより、その表面上に静電潜像が形成（露光された部分は表面電位が上がる）される。本実施例のトナーはマイナス極性に帯電されており、ブラックトナーが入った現像器５によって、感光ドラム１上の静電潜像部にのみマイナストナーが付着し、感光ドラム１上にトナー像が形成される。記録材Ｐは、給紙ローラ４によって給紙されると、搬送ローラ６によって記録材Ｐが転写ニップＮに搬送される。転写ローラ１０に、不図示の電源からトナーの極性とは逆の極性であるプラス極性の転写バイアスが印加され、感光ドラム１上のトナー像は、転写ニップ部Ｎにおいて記録材Ｐ上に転写される。転写後の感光ドラム１は、弾性体ブレードを有する感光ドラムクリーナー１６によって表面の転写残トナーが除去される。トナー像を担持した記録材Ｐは、定着装置１００に搬送され、表面のトナー像の加熱定着が行なわれる。 (Image forming device main unit)
In this embodiment, an example of a method for forming an unfixed toner image on a recording material and an example of an image forming apparatus will be described with reference to a schematic diagram shown in FIG. The image forming apparatus 50 in this embodiment is an electrophotographic image forming apparatus that directly transfers a toner image on a photosensitive drum onto a recording material P. On the peripheral surface of the photosensitive drum 1 as an image carrier, the charger 2, the exposure device 3 for irradiating the photosensitive drum 1 with the laser light L, the developing device 5, and the transfer roller in order along the rotation direction (arrow R1 direction). 10 and a photosensitive drum cleaner 16 are arranged. First, the surface of the photosensitive drum 1 is charged to a negative polarity by the charger 2. Next, an electrostatic latent image is formed on the surface of the charged photosensitive drum 1 by the laser beam L of the exposure means 3 (the surface potential of the exposed portion is increased). The toner of this embodiment is charged with a negative polarity, and the developing device 5 containing black toner attaches the negative toner only to the electrostatic latent image portion on the photosensitive drum 1, and the toner image is formed on the photosensitive drum 1. It is formed. When the recording material P is fed by the paper feed roller 4, the recording material P is transported to the transfer nip N by the transport roller 6. A positive-polarity transfer bias that is opposite to the polarity of the toner is applied to the transfer roller 10 from a power source (not shown), and the toner image on the photosensitive drum 1 is transferred onto the recording material P at the transfer nip N. The The transfer residual toner on the surface of the photosensitive drum 1 after the transfer is removed by a photosensitive drum cleaner 16 having an elastic blade. The recording material P carrying the toner image is conveyed to the fixing device 100, where the toner image on the surface is heated and fixed.

（定着装置）
本実施例の定着装置１００について以下に説明する。図２は、本実施例における定着装置１００の断面図である。 (Fixing device)
The fixing device 100 of this embodiment will be described below. FIG. 2 is a cross-sectional view of the fixing device 100 in this embodiment.

定着装置１００は、定着フィルム１１２と、ヒータ１１３と、ヒータホルダ１３０と、加圧ローラ１１０と、熱伝導部材１４０と、を有する。 The fixing device 100 includes a fixing film 112, a heater 113, a heater holder 130, a pressure roller 110, and a heat conduction member 140.

ヒータ１１３は、定着フィルム１１２の内面に接触し定着フィルム１１２を加熱する。加圧ローラ１１０は、定着フィルム１１２を介してヒータ１１３と共にニップ部Ｎを形成する。加圧ローラ１１０が図中矢印Ｒ１方向に駆動されると、定着フィルム１１２はニップ部Ｎで加圧ローラ１１０から摩擦力を受けて矢印Ｒ２方向に回転する。未定着トナー像Ｔが転写された記録材Ｐが、図中矢印Ａ１方向からニップ部Ｎに搬送されると、トナー像Ｔが記録材に加熱定着されるようになっている。 The heater 113 contacts the inner surface of the fixing film 112 and heats the fixing film 112. The pressure roller 110 forms a nip portion N together with the heater 113 via the fixing film 112. When the pressure roller 110 is driven in the direction of arrow R1 in the drawing, the fixing film 112 receives frictional force from the pressure roller 110 at the nip portion N and rotates in the direction of arrow R2. When the recording material P to which the unfixed toner image T has been transferred is conveyed from the direction of arrow A1 to the nip portion N in the drawing, the toner image T is heated and fixed to the recording material.

定着フィルム１１２について説明する。筒状の定着フィルム１１２は、回転可能に構成され、外力が加えられていないときは外径がφ１８ｍｍの円筒形状である。定着フィルム１１２は、厚み方向において多層構成となっている。定着フィルム１１２は、基層と、基層の外側に形成された離型層と、を有する。基層の材質は、耐熱性や剛性を考慮し、ステンレス鋼やニッケルなどの金属や、ポリイミドなどの耐熱性樹脂が用いられる。本実施例では、定着フィルム１１２の基層の材質としてポリイミド樹脂を用い、熱伝導率と強度を向上させるためカーボン系のフィラーを添加して用いた。基層の厚さは薄いほどヒータ１１３の熱を定着ローラ１１０表面に伝達しやすいが強度が低下するため１５μｍ〜１００μｍ程度が好ましく、本実施例では５０μｍとした。離型層の材質は、パーフルオロアルコキシ樹脂（ＰＦＡ）、ポリテトラフルオロエチレン樹脂（ＰＴＦＥ）、テトラフルオロエチレン−ヘキサフルオロプロピレン樹脂（ＦＥＰ）等のフッ素樹脂が好ましい。本実施例ではフッ素樹脂の中でも離型性と耐熱性に優れるＰＦＡを用いた。離型層は、チューブを被覆させたものでも良いが、表面を塗料でコートしたものでも良く、本実施例では、薄肉成型に優れるコートにより離型層を成型した。離型層は薄いほどヒータ１１３の熱を定着フィルム１１２表面に伝達しやすいが、薄すぎると耐久性が悪化するため、５μｍ〜３０μｍ程度が好ましく、本実施例では１０μｍとした。また、本実施例には使用していないが、基層と離型層の間に、弾性層を設けても良い。その場合、弾性層の材質としては、シリコーンゴムやフッ素ゴムなどが用いられる。 The fixing film 112 will be described. The cylindrical fixing film 112 is configured to be rotatable and has a cylindrical shape with an outer diameter of φ18 mm when no external force is applied. The fixing film 112 has a multilayer structure in the thickness direction. The fixing film 112 has a base layer and a release layer formed outside the base layer. In consideration of heat resistance and rigidity, the base layer is made of a metal such as stainless steel or nickel, or a heat resistant resin such as polyimide. In this example, a polyimide resin was used as the material for the base layer of the fixing film 112, and a carbon-based filler was added to improve the thermal conductivity and strength. The thinner the base layer is, the easier it is to transfer the heat of the heater 113 to the surface of the fixing roller 110, but the strength is reduced. Therefore, the thickness is preferably about 15 μm to 100 μm. The release layer is preferably made of a fluororesin such as perfluoroalkoxy resin (PFA), polytetrafluoroethylene resin (PTFE), tetrafluoroethylene-hexafluoropropylene resin (FEP). In this example, among the fluororesins, PFA having excellent releasability and heat resistance was used. The release layer may be a tube-coated one or a surface coated with a paint. In this example, the release layer was molded by a coating excellent in thin-wall molding. The thinner the release layer is, the easier it is to transfer the heat of the heater 113 to the surface of the fixing film 112. However, if the release layer is too thin, the durability deteriorates, so about 5 to 30 μm is preferable. Although not used in this embodiment, an elastic layer may be provided between the base layer and the release layer. In that case, as the material of the elastic layer, silicone rubber, fluorine rubber, or the like is used.

加圧ローラ１１０について説明する。加圧ローラ１１０の外径は、φ２０ｍｍであり、φ１２ｍｍの鉄製の芯金１１７厚さ４ｍｍの弾性層１１６が形成されている。弾性層１１６の材質としては、ソリッドゴムや、発泡ゴムが用いられる。発泡ゴムは、低熱容量で熱伝導率が低く、加圧ローラ１１０表面の熱が内部へ吸収され難いため、表面温度が上昇しやすく、立ち上がり時間を短縮できる利点がある。本実施例においては、シリコーンゴムを発泡した発泡ゴムを使用した。加圧ローラ１１０の外径は小さい方が熱容量を抑えられるが、小さ過ぎると加圧ニップＮの幅が狭くなってしまうので適度な径が必要であり、本実施例では、外径をφ２０ｍｍとした。弾性層１１６の肉厚に関しても、薄過ぎれば金属製の芯金に熱が逃げるので適度な厚みが必要であり、本実施例では、弾性層１１６の厚さを４ｍｍとした。弾性層１１６の上には、トナーの離型層として、パーフルオロアルコキシ樹脂（ＰＦＡ）からなる離型層１１８が形成されている。離型層１１８は定着フィルム１１２の離型層同様、チューブを被覆させたものでも表面を塗料でコートしたものでも良いが、本実施例では、耐久性に優れるチューブを使用した。離型層１１８の材質としては、ＰＦＡの他に、ＰＴＦＥ、ＦＥＰ等のフッ素樹脂や、離型性の良いフッ素ゴムやシリコーンゴム等を用いても良い。加圧ローラ１１０の表面硬度が低いほど、ニップ部Ｎの幅が広くなる。本実施例では、後述するニップ部Ｎの幅のばらつきと熱伝導部材１４０との熱伝導との関係を検証する為、Ａｓｋｅｒ−Ｃ硬度（４．９Ｎ荷重）で、４８°、５０°、５２°の三水準のものを使用した。加圧ローラ１１０は、不図示の加圧手段により、ヒータに加圧されている。加圧力に関しても、後述するニップ部Ｎのばらつきと熱伝導部材の熱伝導を検証する為、総圧１３ｋｇｆ、１４ｋｇｆ、１５ｋｇｆの３水準を使用した。加圧ローラ１１０は、不図示の回転手段により、図中矢印Ｒ１方向に、表面移動速度２００ｍｍ／ｓｅｃで回転するようになっている。 The pressure roller 110 will be described. The outer diameter of the pressure roller 110 is φ20 mm, and an elastic layer 116 having a thickness of 4 mm and an iron cored bar 117 of φ12 mm is formed. As a material of the elastic layer 116, solid rubber or foamed rubber is used. Foamed rubber has a low heat capacity, low thermal conductivity, and heat on the surface of the pressure roller 110 is difficult to be absorbed into the inside, so that there is an advantage that the surface temperature is likely to rise and the rise time can be shortened. In this example, foamed rubber obtained by foaming silicone rubber was used. If the outer diameter of the pressure roller 110 is smaller, the heat capacity can be suppressed. However, if the pressure roller 110 is too small, the width of the pressure nip N becomes narrower, so that an appropriate diameter is necessary. In this embodiment, the outer diameter is φ20 mm. did. Regarding the thickness of the elastic layer 116, if it is too thin, heat escapes to the metal core, so that an appropriate thickness is necessary. In this embodiment, the thickness of the elastic layer 116 is 4 mm. A release layer 118 made of perfluoroalkoxy resin (PFA) is formed on the elastic layer 116 as a toner release layer. Like the release layer of the fixing film 112, the release layer 118 may be a tube coated or a surface coated with a paint, but in this embodiment, a tube having excellent durability was used. As a material for the release layer 118, in addition to PFA, a fluororesin such as PTFE or FEP, a fluororubber having good releasability, a silicone rubber, or the like may be used. The lower the surface hardness of the pressure roller 110, the wider the width of the nip portion N. In this example, in order to verify the relationship between the variation in the width of the nip portion N described later and the heat conduction with the heat conducting member 140, the Asker-C hardness (4.9 N load) is 48 °, 50 °, 52 Three grades of ° were used. The pressure roller 110 is pressed against the heater by a pressing means (not shown). Regarding the applied pressure, three levels of total pressures of 13 kgf, 14 kgf, and 15 kgf were used in order to verify the variation in the nip portion N described later and the heat conduction of the heat conducting member. The pressure roller 110 is rotated by a rotating means (not shown) in the direction of arrow R1 in the drawing at a surface moving speed of 200 mm / sec.

ヒータ１１３について説明する。ヒータ１１３は、アルミナや窒化アルミなどのセラミック製の基板の上に発熱抵抗体を設けたものを用いている。ヒータ１１３は、定着フィルム１１２の内面に接触する第１の面１１３ａと、第１の面１１３ａの反対側の面である第２の面１１３ｂと、を有する長細い板状の部材である。ヒータ１１３は、記録材搬送方向の幅６ｍｍ、厚さ１ｍｍのアルミナの基板の表面に、Ａｇ／Ｐｄ（銀パラジウム）の発熱抵抗体をスクリーン印刷により１０μｍ塗工し、その上に発熱体保護層としてガラスを５０μｍの厚さで覆ったものを用いた。また、ヒータ１１３あるいは、定着フィルム１１２の温度を検知する不図示の温度検知素子１１５の信号に応じて、ヒータ１１３の発熱抵抗体に供給する電力を制御する。 The heater 113 will be described. The heater 113 uses a heating resistor provided on a ceramic substrate such as alumina or aluminum nitride. The heater 113 is a long and thin plate-like member having a first surface 113a that contacts the inner surface of the fixing film 112 and a second surface 113b that is the surface opposite to the first surface 113a. In the heater 113, a heating resistor of Ag / Pd (silver palladium) is applied to the surface of an alumina substrate having a width of 6 mm and a thickness of 1 mm in the recording material conveying direction by screen printing, and a heating element protective layer is formed thereon. A glass covered with a thickness of 50 μm was used. Further, the power supplied to the heating resistor of the heater 113 is controlled in accordance with a signal from a temperature detection element 115 (not shown) that detects the temperature of the heater 113 or the fixing film 112.

ヒータホルダ１３０について説明する。ヒータホルダ１３０は、ヒータ１１３の第２の面１１３ｂを支持する支持部材である。ヒータホルダ１３０は、耐熱性の樹脂である液晶ポリマー等で形成されている。 The heater holder 130 will be described. The heater holder 130 is a support member that supports the second surface 113 b of the heater 113. The heater holder 130 is formed of a liquid crystal polymer that is a heat-resistant resin.

本実施例の特徴である熱伝導部材１４０について説明する。図３は、ヒータ１１３の長手方向に垂直な断面であって、ヒータ１１３と、熱伝導部材１４０と、の位置関係を拡大して示した概略断面図である。図３（ａ）に示すように、熱伝導部材１４０は、ヒータ１１３の第２の面１１３ｂに接触し、ヒータ１１３とヒータホルダ１３０との間に挟まれている。熱伝導部材１４０のヒータ１１３の第２の面１１３ｂに接触する部分をヒータ接触部１４０ａとする。熱伝導部材１４０は更に、定着フィルム１１２の回転方向（記録材搬送方向）に関しヒータ１１３の端部よりも外側においてヒータ１１３の第２の面１１３ｂから第１の面１１３ａに向かう方向に延び定着フィルム１１２に接触する延長部１４０ｃを有する。延長部１４０ｃは、ヒータ１１３の第１の面１１３ａよりも定着フィルム１１２側に突出している。ヒータ接触部１４０ａはヒータ１１３の摺動面以外のどの面に接触していても良いが、本実施例においては、ヒータ１１３の第２の面１１３ｂに接触するように構成した。熱伝導部材１４０をヒータ１１３の第２の面１１３ｂに接触させることにより、ヒータ１１３に広い面積で接触することが可能になり、加圧ローラ１１０からの加圧力を受けて良好な密着性を得られる利点がある。本実施例においては、熱伝導部材１４０として図３（ａ）に示すような二段曲げ（Ｚ形状）の断面のものを用いたが、図３（ｂ）に示すような一段曲げ（Ｌ形状）のものを用いてもよい。また、熱伝導部材１４０の材質としては、１００Ｗ／ｍ・Ｋ以上の熱伝導率を持つものが望ましい。本実施例においては、熱伝導率が１４０Ｗ／ｍ・Ｋ程度のアルミ合金を用いた。 The heat conducting member 140 that is a feature of the present embodiment will be described. 3 is a cross-sectional view perpendicular to the longitudinal direction of the heater 113 and is an enlarged schematic cross-sectional view showing the positional relationship between the heater 113 and the heat conducting member 140. As shown in FIG. As shown in FIG. 3A, the heat conducting member 140 is in contact with the second surface 113 b of the heater 113 and is sandwiched between the heater 113 and the heater holder 130. A portion of the heat conducting member 140 that contacts the second surface 113b of the heater 113 is referred to as a heater contact portion 140a. The heat conduction member 140 further extends in the direction from the second surface 113b of the heater 113 toward the first surface 113a outside the end of the heater 113 with respect to the rotation direction (recording material conveyance direction) of the fixing film 112. 112 has an extension 140c that contacts 112. The extension portion 140 c protrudes toward the fixing film 112 from the first surface 113 a of the heater 113. The heater contact portion 140a may be in contact with any surface other than the sliding surface of the heater 113, but in this embodiment, the heater contact portion 140a is configured to contact the second surface 113b of the heater 113. By bringing the heat conducting member 140 into contact with the second surface 113b of the heater 113, it becomes possible to make contact with the heater 113 in a wide area and obtain good adhesion by receiving pressure from the pressure roller 110. There are advantages to being In this embodiment, the heat conducting member 140 having a two-step bending (Z-shaped) cross section as shown in FIG. 3A is used, but a one-step bending (L-shaped) as shown in FIG. ) May be used. The material of the heat conducting member 140 is preferably a material having a heat conductivity of 100 W / m · K or more. In this example, an aluminum alloy having a thermal conductivity of about 140 W / m · K was used.

次に、図３（ａ）を用いて、延長部１４０ｃの突出量ｈの定義を説明する。ヒータ１１３の第１の面１１３ａを記録材搬送方向の上流側に延長した線をＳ１とする。ヒータ１１３の第１の面１１３ａに垂直な方向であって第２の面１１３ｂから第１の面１１３ａに向かう方向をａ方向とする。延長部１４０ｃの先端が、線Ｓ１上にあれば０、ａ方向に突出していればその量を正、突出していなければその不足分を負として、その最大値を突出量ｈとする。本実施例においては、ヒータ１１３の第１の面１１３ａがフラットであるものを使用しているがこれに限定されない。図３（ｂ）に示すように、第１の面１１３ａが曲面や傾斜面であっても良い。その場合、ヒータ１１３の短手方向（記録材の搬送方向）の端部において最も加圧ローラ１１０側に突出している部分を通り且つヒータ１１３の第１の面１１３ａに平行である直線をＳ１とし、線Ｓ１について同様の定義をしたものを突出量ｈとする。 Next, the definition of the protrusion amount h of the extension 140c will be described with reference to FIG. A line obtained by extending the first surface 113a of the heater 113 to the upstream side in the recording material conveyance direction is defined as S1. A direction perpendicular to the first surface 113a of the heater 113 and from the second surface 113b toward the first surface 113a is defined as a direction. If the tip of the extension part 140c is on the line S1, the amount is 0 if it protrudes in the a direction, the amount is positive, and if not, the shortage is negative, and the maximum value is the protrusion amount h. In this embodiment, the first surface 113a of the heater 113 is flat, but the present invention is not limited to this. As shown in FIG. 3B, the first surface 113a may be a curved surface or an inclined surface. In that case, a straight line passing through the portion that protrudes most toward the pressure roller 110 at the end of the heater 113 in the short side direction (recording material conveyance direction) and parallel to the first surface 113a of the heater 113 is S1. , The same definition for the line S1 is defined as the protrusion amount h.

延長部１４０ｃを介してヒータ１１３から定着フィルム１１２へ安定的に熱伝導するには、延長部１４０ｃと定着フィルム１１２との接触状態が安定するように構成することが重要である。本実施例では、突出量ｈを確保することによって、延長部１４０ｃと定着フィルム１１２が安定させる。 In order to stably conduct heat from the heater 113 to the fixing film 112 via the extension portion 140c, it is important to configure the contact state between the extension portion 140c and the fixing film 112 to be stable. In this embodiment, the extension 140c and the fixing film 112 are stabilized by securing the protrusion amount h.

本実施例においては、以下の３つの条件で評価した。一つ目は、ニップ部Ｎの加圧力が低く、ローラ硬度が硬く、ニップ部の幅が狭くなる条件（加圧力１３ｋｇｆ、ローラ硬度５２°、加圧ニップ幅５ｍｍ）である。２つ目は、ニップ部Ｎの加圧力が高く、ローラ硬度が低く、ニップ部幅が太くなる条件（加圧力１５ｋｇｆ、ローラ硬度４８°、ニップ部の幅７ｍｍ）である。３つ目は、ニップ部Ｎの加圧力及びローラ硬度が共に中心である条件（加圧力１４ｋｇｆ、ローラ硬度５０°、ニップ部幅６ｍｍ）である。上記３つの条件のそれぞれについて、延長部１４０ｃとフィルム１１２の接触状態の安定性について評価した。 In this example, the evaluation was performed under the following three conditions. The first condition is that the pressure at the nip N is low, the roller hardness is high, and the width of the nip is narrow (pressure 13 kgf, roller hardness 52 °, pressure nip width 5 mm). The second condition is a condition in which the pressing force at the nip portion N is high, the roller hardness is low, and the nip width is large (pressurizing force 15 kgf, roller hardness 48 °, nip width 7 mm). The third condition is that both the pressing force and the roller hardness at the nip portion N are centered (pressurizing force 14 kgf, roller hardness 50 °, nip width 6 mm). For each of the above three conditions, the stability of the contact state between the extension 140c and the film 112 was evaluated.

評価方法を説明する。室温２３℃、相対湿度５０％の環境で評価を行った。ヒータ１１３に電力を供給せずに約１時間放置し、横線画像（２ｄｏｔ／３ｓｐａｃｅ）を１枚通紙し、定着ムラを確認した。用紙はＸＥＲＯＸＶｉｔａｌｉｔｙ（７５ｇ／ｍ^２、ＬＴＲ）を使用した。 An evaluation method will be described. Evaluation was performed in an environment of a room temperature of 23 ° C. and a relative humidity of 50%. The heater 113 was left for about 1 hour without supplying power, and one horizontal line image (2 dots / 3 spaces) was passed to confirm the fixing unevenness. The paper used was XEROX Vitality (75 g / m ² , LTR).

実施例としては、突出量ｈを１００μｍ確保したものを用いて評価した。比較形態として、熱伝導部材の突出量ｈを−１００μｍとした比較形態１と、０μｍとした比較形態２を用いて評価した。 As an example, evaluation was performed using a projection amount h of 100 μm. As comparative forms, evaluation was performed using comparative form 1 in which the protrusion amount h of the heat conducting member was −100 μm and comparative form 2 in which the protrusion amount h was 0 μm.

上記の各条件を評価した結果を表１に示す。まず、突出量ｈを−１００μｍとした比較形態１は、すべてのニップ部幅の場合について、定着ムラが見られた。これは、ニップ付近の定着フィルム１１２の軌道が加圧ローラ１１０と反対側に撓むと、延長部１４０ｃと定着フィルム１１２が接触して熱伝導が行われるのに対し、加圧ローラ１１０側に撓むと、両者が接触せずに伝熱しないためである。次に、突出量ｈを０μｍとした比較形態２は、ニップ部の幅が７ｍｍの場合には、定着ムラが、問題のないレベルまで改善された。これは、ヒータ幅がニップ部の幅よりも狭いことで、ヒータ１１３近傍のニップ内においては、常に延長部１４０ｃと定着フィルム１１２内面とが加圧により接触し熱伝導が行われるためである。ただし、加圧ニップ幅が６ｍｍの場合と、５ｍｍの場合は比較形態１と同様の理由で定着ムラが発生した。最後に、突出量ｈを１００μｍとした実施例においては、すべてのニップ部の幅について、定着性ムラが問題のないレベルにまで改善した。延長部１４０ｃを突出させることによって、定着フィルム１１２の軌道が変化する量よりも、延長部１４０ｃの突出量ｈが大きくなり、定着フィルム１１２の軌道が変化しても延長部１４０ｃとフィルム１１２内面との接触が保たれたためである。 The results of evaluating each of the above conditions are shown in Table 1. First, in Comparative Example 1 in which the protrusion amount h was −100 μm, fixing unevenness was observed for all nip widths. This is because when the track of the fixing film 112 in the vicinity of the nip bends to the opposite side of the pressure roller 110, the extension 140c and the fixing film 112 come into contact with each other to conduct heat, whereas it is bent toward the pressure roller 110. This is because the two do not contact and do not transfer heat. Next, in Comparative Example 2 in which the protrusion amount h was 0 μm, when the width of the nip portion was 7 mm, the fixing unevenness was improved to a level where there was no problem. This is because the heater width is narrower than the width of the nip portion, and in the nip near the heater 113, the extension portion 140c and the inner surface of the fixing film 112 are always brought into contact with each other by pressurization to conduct heat conduction. However, when the pressure nip width was 6 mm and when the pressure nip width was 5 mm, fixing unevenness occurred for the same reason as in Comparative Example 1. Finally, in the example in which the protrusion amount h was 100 μm, the fixing unevenness was improved to a level at which no problem occurred with respect to the widths of all the nip portions. By projecting the extension portion 140c, the protrusion amount h of the extension portion 140c becomes larger than the amount of change of the trajectory of the fixing film 112. Even if the trajectory of the fixing film 112 changes, the extension portion 140c and the inner surface of the film 112 are changed. This is because the contact was maintained.

なお、上記は熱伝導部材１４０の延長部１４０ｃをヒータ１１３の記録材搬送方向の上流側に配置した場合について説明をしたが、必ずしもこれに限定されない。ヒータ１１３の記録材の搬送方向の上流側は下流側よりも、定着フィルム１１２の温度が低いため、上流側に配置にすることにより、延長部１４０ｃからフィルム１１２への熱伝導が効率良く行われる。 Although the above has described the case where the extended portion 140c of the heat conducting member 140 is disposed on the upstream side of the heater 113 in the recording material conveyance direction, the present invention is not necessarily limited thereto. Since the temperature of the fixing film 112 is lower on the upstream side in the recording material conveyance direction of the heater 113 than on the downstream side, the heat conduction from the extension portion 140c to the film 112 is efficiently performed by arranging the fixing film 112 on the upstream side. .

また、本実施例の変形例の構成を示した断面図を図５に示す。本変形例は、延長部１４０ｃを記録材搬送方向に関し上流側と下流側の双方に設けている。図５（ａ）は、曲げ２段からなるＺ形状の曲げを用いた構成、図５（ｂ）は、コの字形状の曲げを用いた構成である。これらの変形例の特徴は、ヒータ１１３から定着フィルム１１２への熱伝導の効率を実施例１よりも更に高めることができる点である。 FIG. 5 is a cross-sectional view showing a configuration of a modification of the present embodiment. In this modification, the extended portions 140c are provided on both the upstream side and the downstream side in the recording material conveyance direction. FIG. 5A shows a configuration using a Z-shaped bend comprising two steps of bending, and FIG. 5B shows a configuration using a U-shaped bend. A feature of these modified examples is that the efficiency of heat conduction from the heater 113 to the fixing film 112 can be further enhanced as compared with the first embodiment.

尚、この変形例において、記録材搬送方向の上流側と下流側の延長部１４０ｃを異なる形状にしても良い。例えば、上流側の延長部１４０ｃはＺ字形状、下流側はＬ字形状の様に任意に選択してよい。 In this modification, the upstream and downstream extensions 140c in the recording material conveyance direction may have different shapes. For example, the upstream extension 140c may be arbitrarily selected such as a Z shape and the downstream side may be an L shape.

以上述べたように、本実施例においては、延長部１４０ｃを、ヒータ１１３の摺動面よりも加圧ローラ１１０側に突出させることで、定着フィルム１１２の回転軌道によらず定着ムラを防止することができる。 As described above, in this embodiment, the extension 140 c is protruded toward the pressure roller 110 from the sliding surface of the heater 113, thereby preventing uneven fixing regardless of the rotation path of the fixing film 112. be able to.

〔実施例２〕
本実施例では、ヒータホルダ１３０の形状が異なるのみで、それ以外の構成は実施例１と同じである。従って、ヒータホルダ１３０以外の構成の説明は省略する。 [Example 2]
In the present embodiment, only the shape of the heater holder 130 is different, and the other configuration is the same as that of the first embodiment. Therefore, the description of the configuration other than the heater holder 130 is omitted.

本実施例においては、延長部１４０ｂの突出量ｈを実施例１と同様に１００μｍに設定している。延長部１４０ｂの定着フィルム１１２の回転方向（記録材搬送方向）の上流側において定着フィルム１１２の回転軌道を規制する規制部１５０を設けている。規制部１５０はヒータホルダ１３０に設けられ、定着フィルム１１２の回転方向における熱伝導部材１４０の延長部１４０ｂの上流側端部よりも外側でヒータ１１３の第２の面１１３ｂから第１の面１１３ａに向かう方向に延びている。規制部１５０は、延長部１４０ｂよりも定着フィルム１１２側に突出している。 In the present embodiment, the protruding amount h of the extended portion 140b is set to 100 μm as in the first embodiment. A regulating unit 150 that regulates the rotation trajectory of the fixing film 112 is provided on the upstream side of the extending portion 140b in the rotation direction of the fixing film 112 (recording material conveyance direction). The restricting portion 150 is provided in the heater holder 130, and is directed from the second surface 113 b of the heater 113 to the first surface 113 a outside the upstream end portion of the extension portion 140 b of the heat conducting member 140 in the rotation direction of the fixing film 112. Extending in the direction. The restricting portion 150 protrudes closer to the fixing film 112 than the extension portion 140b.

規制部１５０の突出量ｈ’の定義について図６（ｃ）を用いて説明する。延長部１４０ｂの突出量ｈを定義した時と同様に、ヒータ１１３の定着フィルム１１２と接触する面（第１の面）を記録材搬送方向の上流側に延長した直線をＳ１、ヒータ１１３の第１の面に垂直な方向をａとする。延長部１４０ｂの突出量ｈが定義される最大突出部を通りＳ１と平行な直線をＳ２とする。規制部１５０の最大突出部がＳ１上にあれば突出量は０、ａ方向に突出していればその突出量を正の値として、最大値を規制部１５０の突出量ｈ’とする。本実施例における規制部１５０の突出量ｈ’は、定着フィルム１１２の回転軌道を安定的に規制できるように２００μｍとしている。 The definition of the protrusion amount h ′ of the restricting portion 150 will be described with reference to FIG. Similarly to the case where the protrusion amount h of the extension portion 140b is defined, a straight line obtained by extending the surface (first surface) of the heater 113 in contact with the fixing film 112 to the upstream side in the recording material conveyance direction is S1, and the heater 113 A direction perpendicular to the surface of 1 is a. Let S2 be a straight line that passes through the maximum protruding portion where the protruding amount h of the extending portion 140b is defined and is parallel to S1. If the maximum protrusion of the restricting portion 150 is on S1, the protrusion amount is 0. If the protrusion is in the a direction, the protrusion amount is a positive value, and the maximum value is the protrusion amount h 'of the restricting portion 150. In this embodiment, the protrusion h ′ of the restricting portion 150 is set to 200 μm so that the rotation trajectory of the fixing film 112 can be stably restricted.

ヒータホルダ１３０の規制部１５０の効果について評価する。本実施例においては、より厳しい条件で評価を行うため、低温環境で評価を行った。低温環境においては、ヒータ１１３および延長部１４０ｂから定着フィルム１１２への伝熱量が、常温環境よりも大きいため、延長部１４０ｂと定着フィルム１１２の接触面積の振れも定着ムラの発生に繋がる。本実施例の構成は、定着フィルム１１２と熱伝導部材１４０との接触状態を安定させる効果を奏する。 The effect of the restriction part 150 of the heater holder 130 is evaluated. In this example, evaluation was performed in a low temperature environment in order to perform evaluation under more severe conditions. In a low-temperature environment, the amount of heat transferred from the heater 113 and the extension part 140b to the fixing film 112 is larger than that in the normal temperature environment, so that the fluctuation of the contact area between the extension part 140b and the fixing film 112 also leads to occurrence of fixing unevenness. The configuration of this embodiment has an effect of stabilizing the contact state between the fixing film 112 and the heat conducting member 140.

本実施例の評価方法は、評価する環境を除くと実施例１と同様である。環境は室温１５℃相対湿度１０％の低温低湿環境とした。ヒータ１１３に電力を供給せずに１時間程度放置し、横線画像（２ｄｏｔ／３ｓｐａｃｅ）を１枚通紙し、定着ムラを確認した。用紙はＸＥＲＯＸＶｉｔａｌｉｔｙ（７５ｇ／ｍ^２、ＬＴＲ）を使用した。 The evaluation method of this example is the same as that of Example 1 except for the environment to be evaluated. The environment was a low temperature and low humidity environment with a room temperature of 15 ° C. and a relative humidity of 10%. The heater 113 was left for about 1 hour without supplying power, and one horizontal line image (2 dots / 3 spaces) was passed, and fixing unevenness was confirmed. The paper used was XEROX Vitality (75 g / m ² , LTR).

図６（ａ）（ｂ）は実施例１の構成である。延長部１４０ｂのヒータ１１３の第１の面１１３ａからの突出量ｈを１００μｍ以上とし、規制部１５０を設けていないときの定着フィルム１１２の回転軌道を、延長部１４０ｂを中心に拡大した概略図である。この構成の場合、定着フィルム１１２の回転軌道が変化しても、定着フィルム１１２内面は、延長部１４０ｂの一部と接触を保つことは可能であり、定着ムラを抑制できる。しかしながら、図６（ａ）のように定着フィルム１１２の回転軌道が延長部１４０ｂに沿った形状となっているときは接触面積が大きく、図６（ｂ）のように定着フィルム１１２の軌道が加圧ローラ側に大きく撓んでいる場合は接触面積が小さくなる。特に低温環境における定着装置１００の起動時は、ヒータ１１３からフィルム１１２への伝熱量が大きいため、この接触面積の変化の影響を受けて定着ムラが発生しやすい。 6A and 6B show the configuration of the first embodiment. A schematic diagram in which the protrusion h of the extension portion 140b from the first surface 113a of the heater 113 is set to 100 μm or more, and the rotation trajectory of the fixing film 112 when the restriction portion 150 is not provided is enlarged around the extension portion 140b. is there. In the case of this configuration, even if the rotation trajectory of the fixing film 112 changes, the inner surface of the fixing film 112 can be kept in contact with a part of the extension portion 140b, and fixing unevenness can be suppressed. However, when the rotation trajectory of the fixing film 112 is shaped along the extension 140b as shown in FIG. 6A, the contact area is large, and the trajectory of the fixing film 112 is added as shown in FIG. 6B. When it is greatly bent toward the pressure roller, the contact area is reduced. In particular, when the fixing device 100 is started in a low temperature environment, the amount of heat transferred from the heater 113 to the film 112 is large, and therefore, unevenness of fixing tends to occur due to the influence of this change in contact area.

一方、本実施例の構成においては、規制部１５０を設けて定着フィルム１１２の回転軌道を予め加圧ローラ１１０側に撓ませておくことにより、定着フィルム１１２の回転軌道の変化を抑制し、延長部１４０ｂとの接触面積の振れを安定化することができる。 On the other hand, in the configuration of the present embodiment, the restriction portion 150 is provided so that the rotation trajectory of the fixing film 112 is bent in advance toward the pressure roller 110, thereby suppressing the change in the rotation trajectory of the fixing film 112 and extending it. The fluctuation of the contact area with the portion 140b can be stabilized.

更に、規制部１５０を設けることの別の利点として、延長部１４０ｂの記録材搬送方向の上流側のエッジ１４０ｃが定着フィルム１１２と接触することを抑制することができるということがある。図６（ａ）のように定着フィルム１１２の回転軌道が延長部１４０ｂに沿っている場合、延長部１４０ｂのエッジ１４０ｃが定着フィルム１１２内面と摺動する。熱伝導部材１４０を熱伝導性の高いアルミニウム等の金属板で作製する場合、そのエッジは鋭利になっていることがある。この熱伝導部材１４０のエッジが定着フィルム１１２の内面と摺動すると、定着フィルム１１２が削れやすい。そのため、延長部１４０ｂのエッジ１４０ｃは定着フィルム１１２の内面に接触しないようにすることが望ましい。図６（ｃ）に示すように、延長部１４０ｂの定着フィルム１１２の内面と摺動する部分と、規制部１５０の突出部と、を結んだ直線Ｌに対して、延長部１４０ｂのエッジ１４０ｃが加圧ローラ１１０と反対側に位置するように配置する。 Furthermore, another advantage of providing the restricting portion 150 is that the upstream edge 140c of the extension portion 140b in the recording material conveyance direction can be prevented from coming into contact with the fixing film 112. When the rotation trajectory of the fixing film 112 is along the extension portion 140b as shown in FIG. 6A, the edge 140c of the extension portion 140b slides on the inner surface of the fixing film 112. When the heat conductive member 140 is made of a metal plate such as aluminum having high heat conductivity, the edge may be sharp. When the edge of the heat conducting member 140 slides on the inner surface of the fixing film 112, the fixing film 112 is easily scraped. Therefore, it is desirable that the edge 140c of the extension 140b does not contact the inner surface of the fixing film 112. As shown in FIG. 6C, an edge 140c of the extension 140b is formed with respect to a straight line L connecting the portion of the extension 140b that slides with the inner surface of the fixing film 112 and the protrusion of the restricting portion 150. It arrange | positions so that it may be located on the opposite side to the pressure roller 110. FIG.

尚、実施例１の場合と同様に、熱伝導部材１４０の延長部１４０ｂをヒータ１１３の記録材搬送方向の上流側に配置した場合について説明をしたが、これに限定されない。つまり、図７に示す本実施例の変形例１のように、延長部１４０ｂをヒータ１１３の定着フィルム１１２の回転方向（記録材搬送方向）の下流側に配置した場合にも本実施例は適用できる。また、図８に示す本実施例の変形例２のように記録材搬送方向の上下流側に配置した構成でも本実施例を適用できる。 As in the case of the first embodiment, the case where the extended portion 140b of the heat conducting member 140 is disposed on the upstream side in the recording material conveyance direction of the heater 113 has been described, but the present invention is not limited to this. That is, as in Modification 1 of the present embodiment shown in FIG. 7, the present embodiment is also applied to the case where the extended portion 140b is arranged on the downstream side of the rotation direction (recording material conveyance direction) of the fixing film 112 of the heater 113. it can. Further, the present embodiment can also be applied to a configuration arranged on the upstream and downstream sides in the recording material conveyance direction as in Modification 2 of the present embodiment shown in FIG.

〔実施例３〕
本発明の実施例３について以下に説明する。実施例３についても、熱伝導部材１４０の延長部１４０ｂとヒータホルダ１３０の形状が異なるのみで、それ以外の構成は実施例１と変わらないため、本体の詳細構成の説明は省略する。 Example 3
Example 3 of the present invention will be described below. Also in the third embodiment, only the shapes of the extended portion 140b of the heat conducting member 140 and the heater holder 130 are different, and the other configuration is the same as that of the first embodiment, so that the detailed configuration of the main body is not described.

本実施例の規制部１５０について図９（ａ）（ｂ）を用いて説明する。本実施例において、延長部１４０ｂの突出量ｈは、実施例１と同様に１００μｍとしている。更に、延長部１４０ｂの記録材搬送方向の上流側の端部を定着フィルム１１２の内面（加圧ローラ１１０）から遠ざかる方向に折り返して定着フィルム内面に接触する部分を曲面形状にしている。図９（ａ）のように、定着フィルム１１２の回転軌道が延長部１４０ｂに沿っている場合と、図９（ｂ）のように定着フィルム１１２の回転軌道が加圧ローラ１１０側に大きく撓んでいる場合と、で延長部１４０ｂと定着フィルム１１２の接触面積が変わりにくい。その結果、低温の環境であっても、熱伝導部材１４０を介してヒータ１１３の熱を定着フィルム１１２に安定して供給できるので定着ムラを抑制することができる。 The restriction part 150 of the present embodiment will be described with reference to FIGS. 9 (a) and 9 (b). In the present embodiment, the protruding amount h of the extension portion 140b is set to 100 μm as in the first embodiment. Further, the end of the extension 140b on the upstream side in the recording material conveyance direction is folded back in a direction away from the inner surface (pressure roller 110) of the fixing film 112, so that the portion contacting the inner surface of the fixing film is curved. As shown in FIG. 9A, when the rotation trajectory of the fixing film 112 is along the extension 140b, the rotation trajectory of the fixing film 112 is greatly bent toward the pressure roller 110 as shown in FIG. 9B. The contact area between the extension portion 140b and the fixing film 112 is less likely to change. As a result, even in a low temperature environment, the heat of the heater 113 can be stably supplied to the fixing film 112 via the heat conducting member 140, so that uneven fixing can be suppressed.

尚、実施例１の場合と同様に、熱伝導部材１４０の延長部１４０ｂをヒータ１１３の記録材搬送方向の上流側に配置した場合について説明をしたが、これに限定されない。図１０に示す本実施例の変形例１のように、延長部１４０ｂをヒータ１１３の記録材搬送方向の下流側に配置した構成でも良い。また、図１１に示す本実施例の変形例２のように、延長部１４０ｂを記録材搬送方向の上下流側に配置した構成でも良い。 As in the case of the first embodiment, the case where the extended portion 140b of the heat conducting member 140 is disposed on the upstream side in the recording material conveyance direction of the heater 113 has been described, but the present invention is not limited to this. As in Modification 1 of this embodiment shown in FIG. 10, the extension 140 b may be arranged on the downstream side of the heater 113 in the recording material conveyance direction. Further, as in Modification 2 of the present embodiment shown in FIG. 11, a configuration in which the extension portion 140b is arranged on the upstream and downstream sides in the recording material conveyance direction may be used.

〔実施例４〕
本実施例においては、図１２〜図１４を参照しながら、熱伝導部材１４０の延長部１４０ｂの長手端部とヒータホルダ１３０の構成について説明する。本実施例は、実施例１の構成に対して熱伝導部材１４０の長手端部と、ヒータホルダ１３０の長手端部と、を除いて同じ構成なので、それらの説明については省略する。 Example 4
In the present embodiment, the configuration of the longitudinal end portion of the extension 140b of the heat conducting member 140 and the heater holder 130 will be described with reference to FIGS. Since the present embodiment has the same configuration as the configuration of the first embodiment except for the longitudinal end portion of the heat conducting member 140 and the longitudinal end portion of the heater holder 130, description thereof will be omitted.

図１２はフィルムユニット１０００をヒータ１１３側から見た斜視図である。図１３はフィルムユニット１０００の長手端部の拡大図であり、図１３（ａ）は定着フィルム１１２を表示した図、図１３（ｂ）は定着フィルム１１２を非表示にした図である。図１３に示すように、熱伝導部材１４０の延長部１４０ｂの長手端面１４０ｄは定着フィルム１１２の長手方向において定着フィルム１１２の長手端部よりも内側に配置されている。
ところで、熱伝導部材１４０としてアルミ合金等の金属板を使用する場合、熱伝導部材１４０はプレス加工で製造されることが多い。従って、この熱伝導部材１４０の長手端面１４０ｄのエッジが定着フィルム１１２と強く接触しながら摺動すると定着フィルム１１２が削れやすいという課題がある。 FIG. 12 is a perspective view of the film unit 1000 as viewed from the heater 113 side. FIG. 13 is an enlarged view of the longitudinal end of the film unit 1000, FIG. 13 (a) shows the fixing film 112, and FIG. 13 (b) shows the fixing film 112 hidden. As shown in FIG. 13, the longitudinal end surface 140 d of the extension portion 140 b of the heat conducting member 140 is disposed inside the longitudinal end portion of the fixing film 112 in the longitudinal direction of the fixing film 112.
By the way, when using metal plates, such as an aluminum alloy, as the heat conductive member 140, the heat conductive member 140 is often manufactured by press work. Therefore, if the edge of the longitudinal end surface 140d of the heat conducting member 140 slides while being in strong contact with the fixing film 112, there is a problem that the fixing film 112 is easily scraped.

上記課題を解決するために、本実施例の特徴は、図１３（ｂ）に示すように、ヒータ１１３の長手方向において、熱伝導部材１４０の長手端面１４０ｄよりも外側のヒータホルダ１３０の部分にフィルム接触部１３０ａを設けている点である。このフィルム接触部１３０ａについて図１４を用いて説明する。図１４は、フィルムユニット１０００の長手端部のヒータ１１３の長手方向に垂直な断面図である。図１４に示すように、フィルム接触部１３０ａは延長部１４０ｂよりも矢印ａ方向に突出している。矢印ａ方向は、ヒータ１１３の第２の面１１３ｂから第１の面１１３ａに向かう方向である。この構成により、定着フィルム１１２がフィルム接触面１３０ａに接触して支持されるので、定着フィルム１１２が熱伝導部材１４０の長手端面１４０ｄのエッジに強く接触することを防止することができる。更に、ヒータホルダ１３０は樹脂で形成することができるので、フィルム接触面１３０ａの長手端面１４０ｄと対向する面の稜線部を曲面になるように形成し、定着フィルム１１２の摩耗を抑制することができる。また、熱伝導部材１４０の延長部１４０ｂ側の面をプレス加工におけるダレ側に設定することで、端部端面１４０ｄの定着フィルム１１２側の稜線部がダレ側となり、定着フィルム１１２の摩耗をより防止することができる。 In order to solve the above problems, the present embodiment is characterized in that a film is formed on the heater holder 130 outside the longitudinal end surface 140d of the heat conducting member 140 in the longitudinal direction of the heater 113 as shown in FIG. The contact point 130a is provided. The film contact portion 130a will be described with reference to FIG. FIG. 14 is a cross-sectional view perpendicular to the longitudinal direction of the heater 113 at the longitudinal end of the film unit 1000. As shown in FIG. 14, the film contact part 130a protrudes in the arrow a direction from the extension part 140b. The direction of arrow a is the direction from the second surface 113b of the heater 113 toward the first surface 113a. With this configuration, since the fixing film 112 is supported in contact with the film contact surface 130 a, it is possible to prevent the fixing film 112 from coming into strong contact with the edge of the longitudinal end surface 140 d of the heat conducting member 140. Furthermore, since the heater holder 130 can be made of resin, the ridge line portion of the surface of the film contact surface 130a that faces the longitudinal end surface 140d can be formed to be a curved surface, and wear of the fixing film 112 can be suppressed. Further, by setting the surface of the heat conducting member 140 on the side of the extended portion 140b to be the sag side in the press working, the ridge line portion on the fixing film 112 side of the end surface 140d becomes the sag side, thereby further preventing wear of the fixing film 112. can do.

尚、図１２の定着フィルムユニットの一方の長手端部について説明したが、他方の長手端部についても同様の構成である。また、フィルム接触面１３０ａは、延長部１４０ｂと同一面になるように構成しても良い。 Although one longitudinal end of the fixing film unit in FIG. 12 has been described, the other longitudinal end has the same configuration. Moreover, you may comprise the film contact surface 130a so that it may become the same surface as the extension part 140b.

また、本実施例では、熱伝導部材１４０の延長部１４０ｂを記録材搬送方向においてヒータ１１３の上流側に配置した場合について説明をした。その理由として、ヒータ１１３の記録材搬送方向の上流側は下流側よりも定着フィルム１１２の温度が低いので、上流側に延長部１４０ｂを配置にすることにより、延長部１４０ｂから定着フィルム１１２への熱伝導を効率的に行うことができるためである。しかしながら、図４に示す構成のように記録材搬送方向におけるヒータ１１３の下流側に延長部１４０ｂを配置する構成でも良い。 In the present embodiment, the case where the extended portion 140b of the heat conducting member 140 is disposed on the upstream side of the heater 113 in the recording material conveyance direction has been described. The reason for this is that the upstream side of the heater 113 in the recording material conveyance direction has a lower temperature of the fixing film 112 than the downstream side. Therefore, by arranging the extension part 140b on the upstream side, the extension part 140b is connected to the fixing film 112. This is because heat conduction can be performed efficiently. However, a configuration in which the extension 140b is disposed on the downstream side of the heater 113 in the recording material conveyance direction as shown in FIG.

また、実施例１で説明した図３と図４に示した構成を組み合わせて、図５に示すように熱伝導部材１４０の延長部１４０ｂをヒータ１１３の記録材搬送方向の上流及び下流の双方に配置すると、定着フィルム１１２への熱伝達をさらに高めることができる。 Further, by combining the configurations shown in FIGS. 3 and 4 described in the first embodiment, the extension 140b of the heat conducting member 140 is provided both upstream and downstream in the recording material conveyance direction of the heater 113 as shown in FIG. When arranged, heat transfer to the fixing film 112 can be further enhanced.

図１５、１６は、実施例４の変形例のフィルムユニット２０００の長手端部の斜視図（定着フィルム１１３は非表示）と、ヒータ１１３の長手方向に垂直な断面図である。本変形例においては、ヒータホルダ１３０のフィルム接触面１３０ａと熱伝導部材１４０の延長部１４０ｂとがヒータ１１３の記録材搬送方向の上流及び下流の双方に配置されている。図１６に示すように、ヒータホルダ１３０のフィルム接触面１３０ａは熱伝導部材１４０の延長部１４０ｂよりも矢印ａ方向に突出している。矢印ａ方向は、延長部１３０ａが対向している定着フィルム１１２の内面に近づく方向である。また、フィルム接触面１３０ａは延長部１４０ｂと同一面でもよい。 FIGS. 15 and 16 are a perspective view of the longitudinal end portion of the film unit 2000 according to a modification of the fourth embodiment (the fixing film 113 is not shown) and a cross-sectional view perpendicular to the longitudinal direction of the heater 113. In this modification, the film contact surface 130a of the heater holder 130 and the extended portion 140b of the heat conducting member 140 are disposed both upstream and downstream in the recording material conveyance direction of the heater 113. As shown in FIG. 16, the film contact surface 130 a of the heater holder 130 protrudes in the arrow a direction from the extension 140 b of the heat conducting member 140. The arrow a direction is a direction approaching the inner surface of the fixing film 112 facing the extension 130a. The film contact surface 130a may be the same surface as the extension 140b.

尚、本実施例、本実施例の変形例においては、フィルムユニットの長手方向の一端側について説明したが、他端側も同様の構成である。 In addition, in the present Example and the modification of this Example, although the one end side of the longitudinal direction of the film unit was demonstrated, the other end side is also the same structure.

また、本実施例及び本実施例の変形例の構成を実施例２及び３の熱伝導部材に適用しても同様の効果が得られる。 Further, the same effect can be obtained even when the configurations of the present embodiment and the modified example of the present embodiment are applied to the heat conducting members of the second and third embodiments.

１００定着装置
１１０加圧ローラ
１１２定着フィルム
１１３ヒータ
１３０ヒータホルダ
１３０ａフィルム接触面
１４０熱伝導部材
１４０ｂ延長部
１４０ｄ延長部の端面
１５０フィルム軌道の規制部材 DESCRIPTION OF SYMBOLS 100 Fixing device 110 Pressure roller 112 Fixing film 113 Heater 130 Heater holder 130a Film contact surface 140 Thermal conduction member 140b Extension part 140d End surface of extension part 150 Film track regulating member

Claims

A rotatable cylindrical film,
A plate-shaped heater having a first surface and a second surface opposite to the first surface, the long and thin plate-shaped heater contacting the inner surface of the film on the first surface;
A heat conducting member that is long in the longitudinal direction of the heater and is in contact with the second surface of the heater;
A fixing device that heats a toner image with the heat of the heater via the film and fixes the toner image on a recording material.
The heat conducting member has an extension that extends in the direction from the second surface of the heater toward the first surface outside the upstream end of the heater in the rotation direction of the film,
The extension unit protrudes from the first surface of the heater toward the film and contacts the film.

A support member for supporting the heater via the heat conducting member;
The support member includes a restricting portion extending in a direction from the second surface of the heater toward the first surface outside the upstream end portion of the extension portion of the heat conducting member in the rotation direction of the film. The fixing device according to claim 1, wherein the restricting portion protrudes closer to the film than the extension portion.

The end face of the extension part of the heat conducting member in the longitudinal direction of the heater is provided inside the end face of the film,
A support member that extends to the outside of the end surface of the extension in the longitudinal direction of the heater and supports the heater via the heat conducting member;
An extension is provided in the portion of the support member that is outside the end face of the extension in the longitudinal direction of the heater;
The fixing device according to claim 1, wherein the extension portion protrudes toward the film from a surface of the extension portion that faces the inner surface of the film.