JPS61212873A - Fixing device for electronic copying machine - Google Patents

Fixing device for electronic copying machine

Info

Publication number
JPS61212873A
JPS61212873A JP5248685A JP5248685A JPS61212873A JP S61212873 A JPS61212873 A JP S61212873A JP 5248685 A JP5248685 A JP 5248685A JP 5248685 A JP5248685 A JP 5248685A JP S61212873 A JPS61212873 A JP S61212873A
Authority
JP
Japan
Prior art keywords
roll
fixing
pressure roll
outer diameter
pressure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP5248685A
Other languages
Japanese (ja)
Inventor
Hiroo Nishide
西出 裕勇
Hideo Saito
秀夫 斉藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujifilm Business Innovation Corp
Original Assignee
Fuji Xerox Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fuji Xerox Co Ltd filed Critical Fuji Xerox Co Ltd
Priority to JP5248685A priority Critical patent/JPS61212873A/en
Publication of JPS61212873A publication Critical patent/JPS61212873A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00Apparatus for electrographic processes using a charge pattern
    • G03G15/20Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat
    • G03G15/2003Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat using heat
    • G03G15/2014Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat using heat using contact heat
    • G03G15/2017Structural details of the fixing unit in general, e.g. cooling means, heat shielding means
    • G03G15/2032Retractable heating or pressure unit

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Fixing For Electrophotography (AREA)
  • Control Of Resistance Heating (AREA)

Abstract

PURPOSE:To fix stably a picture without fail by providing an outer diameter detecting means of a pressure roll pressing a fixing paper to a heater incorporating fixing roll, and allowing the pressure roll to contact with the fixing roll and rotate when the outer diameter is smaller than a reference, and expanding said diameter by the frictional heat. CONSTITUTION:In terms of fixing a toner image, the fixing roll 1 incorporating the heater 2 is provided with the outer diameter detecting means 7 of the pressure roll 3 pressing a fixing paper 4. In terms of the pressure roll 3, the periphery of a core 3a made of metal, for instance, is coated with a silicone rubber elastic layer 3b, and the surface is coated with a peel-off type layer 3c made of a 'Teflon(R)' thermal contraction tube. At a fixing position shown by a solid lien and a standby position shown by a broken line, a detecting means 7 is supported by a lever 11 where a detecting lever 9 adjacent to the roll 3 is made movable by a guide roll 10, and one end of the lever 11 is connected to a position detector 12, whereby an increase or decrease in the diameter of the roll 3 is electrically detected. When a detected current is less than a reference value, the roll 3 is brought into contact with the roll 2 and is rotated in such a way that the outer diameter is thermal by expanded until said current reaches the reference value. Thus the appropriate fixing can be possible without fail.

Description

【発明の詳細な説明】 産業上の利用分野 この発明は用紙上に転写されたトナー像を用紙に熱定着
する電子複写機の定着装置に関する。
DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a fixing device for an electronic copying machine that thermally fixes a toner image transferred onto a sheet of paper.

従来の技術 従来電子複写機に用いられる定着装置とじて第5図に示
すものが公知である。上記定着装置はヒータaを内装し
た定着ロールbと、定着すべき用紙dを上記定着ロール
bへ圧接する加圧ロールeとよりなり、定着ロールbの
表面はテフロンやシリコーンゴムなとの離型層fで被覆
されている。
2. Description of the Related Art A fixing device shown in FIG. 5 is known as a fixing device used in a conventional electronic copying machine. The fixing device consists of a fixing roll b equipped with a heater a, and a pressure roll e that presses the paper d to be fixed onto the fixing roll b, and the surface of the fixing roll b is coated with a release material such as Teflon or silicone rubber. It is coated with a layer f.

また加圧ロールeは表面がシリコーンゴムなどの弾性層
gで被覆されており、これら定着ロールb及び加圧ロー
ルeは軸間距離が一定となるようフレームに支承されて
いる。
The surface of the pressure roll e is covered with an elastic layer g made of silicone rubber, and the fixing roll b and pressure roll e are supported by a frame so that the distance between their axes is constant.

発明が解決しようとする問題点 上記のような定着装置では、定着時に最適なニップ幅が
定着ロールbと加圧ロールeの間で得られるよう両ロー
ルb、eの軸間距離が設定されている。しかし加圧ロー
ルeが冷えていて、径が細い状態では十分なニップ幅及
びニップ圧が得られず定着不良が発生することから、従
来では加圧ロールe内にも加熱ランプなどの熱源を入れ
て、加圧ロールeを内部より加熱するよう対策したもの
が例えば特開昭56−57070号公報などで提案され
ている。しかしこの方法では肉厚の厚い弾性層gの内側
より加熱するため、弾性層gの内側だけが異常に高温と
なる”不具合があると共に、これを改善するため弾性層
gの肉厚を薄くすると十分なニップ幅及びニップ圧が得
られなくなる。
Problems to be Solved by the Invention In the above-described fixing device, the distance between the axes of the fixing rolls b and e is set so that an optimal nip width is obtained between the fixing roll b and the pressure roll e during fixing. There is. However, if the pressure roll e is cold and the diameter is small, sufficient nip width and nip pressure cannot be obtained, resulting in poor fixing. Therefore, a method has been proposed in which the pressure roll e is heated from the inside, for example, in Japanese Patent Laid-Open No. 56-57070. However, in this method, heating is performed from the inside of the thick elastic layer g, so there is a problem that only the inside of the elastic layer g becomes abnormally high temperature. Sufficient nip width and nip pressure cannot be obtained.

上記加圧ロールeの熱膨張による径の変化を考慮して両
ロールb、eの軸間距離を固定せず、一方のロールを他
方のロールへばね等の付勢手段で圧接させるようにした
ものも実施されている。しかしこの方法では両ロールb
、e間に100〜400 Kgもの付勢力を加える必要
があることから、強力な圧縮ばねを必要とするなど付勢
手段が大型となる不具合がある。
Considering the change in diameter of the pressure roll e due to thermal expansion, the distance between the axes of both rolls b and e is not fixed, and one roll is brought into pressure contact with the other roll using a biasing means such as a spring. Things are also being implemented. However, with this method, both roles b
, e, it is necessary to apply a biasing force of 100 to 400 Kg, which results in the disadvantage that the biasing means becomes large in size, such as requiring a strong compression spring.

また別の方法として定着ロールのウオームアツプ後設定
温度に達する少し前に、定着ロール及び加圧ロールを接
触回転させて、定着ロールで加圧ロールの表面を加熱す
るようにしたものが例えば特開昭56−142563号
公報などで公知である。この方法では加圧ロールの表面
温度を検出して、所定温度に達したところで両ロールの
接触回転を停止するか、予め設定した時間両ロールを接
触回転させた後停止させることにより加圧ロールの予熱
を完了している。
Another method is to heat the surface of the pressure roll with the fixing roll by rotating the fixing roll and the pressure roll in contact with each other a little before the temperature reaches the set temperature after the fuser roll has warmed up, for example in Japanese Patent Publication No. This is known from Publication No. 56-142563. In this method, the surface temperature of the pressure roll is detected, and the contact rotation of both rolls is stopped when a predetermined temperature is reached, or the pressure roll is rotated in contact with each other for a preset time and then stopped. Preheating has been completed.

しかし前者の加圧ロールeの表面温度を検出する方法で
は、弾性層gの熱伝導率が低いことから、弾性層gの内
部まで十分に加熱されることなしに加圧ロールeの予熱
が完了してしまうため、加圧ロールeの径が所定の太さ
に達せず定着不良の原因となる不具合がある。
However, in the former method of detecting the surface temperature of the pressure roll e, because the thermal conductivity of the elastic layer g is low, the preheating of the pressure roll e is completed without sufficiently heating the inside of the elastic layer g. Therefore, there is a problem that the diameter of the pressure roll e does not reach a predetermined thickness, resulting in poor fixing.

また後者の所定時間両ロールb、eを接触回転させるも
のにあっては、環境温度等によって本来必要な接触回転
時間が異なることから、もつとも悪い条件下でも安定し
た定着が得られるよ5W触回転時間を設定する必要があ
り、その結果条件のよいときには加圧ロールeが加熱し
すぎて径が大きくなり、定着ロールbへのオフセットが
増加する不具合があった。
In addition, in the case of the latter method in which both rolls b and e are rotated in contact for a predetermined period of time, since the required contact rotation time differs depending on the environmental temperature, etc., stable fixing can be obtained even under adverse conditions. It is necessary to set the time, and as a result, when the conditions are good, the pressure roll e is heated too much and its diameter becomes large, resulting in an increase in offset to the fixing roll b.

この発明は上記従来の不具合を改善する目的でなされた
ものである。
This invention has been made to improve the above-mentioned conventional problems.

問題点を解決するための手段および作用ヒータを内装し
た定着ロールに加圧ロールにより定着すべき用紙を圧着
して、用紙上のトナー像を用紙に熱定着するものにおい
て、上記加圧ロールの近傍に、加圧ロールの外径を検出
する検出手段を設けて、この検出手段により検出された
値が基準値より小さい場合に加圧ロールを定着ロールに
圧着させて、加圧ロールが基準値となるまで両ロールを
接触回転させることにより、常に一定したニップ幅及び
ニップ圧で定着を可能とした電子複写機の定着装置。
Means for Solving Problems and Effects In an apparatus for thermally fixing the toner image on the paper by pressing the paper to be fixed onto the fixing roll equipped with a heater with a pressure roll, A detection means for detecting the outer diameter of the pressure roll is provided, and when the value detected by the detection means is smaller than a reference value, the pressure roll is pressed against the fixing roll, and the pressure roll is set to the reference value. A fixing device for an electronic copying machine that enables fixing with a constant nip width and nip pressure by rotating both rolls in contact with each other until the nip width and nip pressure are constant.

芙施例 この発明の一実施例を図面を参照して詳述すると、第1
図において1はヒータ2を内装した定着ロールで、アル
ミニウムなどの金属よりなるコア1aの周囲をテフロン
よりなる離型層1bで被覆することにより形成されてお
り、コア1a内に加熱ランプよりなるヒータ2が収容さ
れている。3は定着すべき用紙4を上記定着ロールIへ
圧接する加圧ロールで、鉄などの金属よりなるコア3a
の周囲をシリコーンゴムよりなる弾性層3bで被覆し、
さらにその表面をテフロン熱収縮チューブよりなる離型
層3Cで被覆することにより形成されている。なお、5
は用紙ガイド、6は定着ロール1に付着した用紙4を剥
離する剥離爪を示す。
Embodiment One embodiment of the present invention will be described in detail with reference to the drawings.
In the figure, reference numeral 1 denotes a fixing roll incorporating a heater 2, which is formed by covering a core 1a made of metal such as aluminum with a release layer 1b made of Teflon, and a heater made of a heating lamp inside the core 1a. 2 is accommodated. A pressure roll 3 presses the paper 4 to be fixed onto the fixing roll I, and has a core 3a made of metal such as iron.
Covering the periphery with an elastic layer 3b made of silicone rubber,
Further, the surface thereof is coated with a release layer 3C made of a Teflon heat-shrinkable tube. In addition, 5
6 indicates a paper guide, and 6 indicates a peeling claw for peeling off the paper 4 attached to the fixing roll 1.

一方上記定着ロール1及び加圧ロール3は図示しないベ
アリングを介してフレームに回転自在に支承されている
と共に、加圧ロール3は定着ロール1に対して接離方向
へ移動自在となっていて、定着時及び加圧ロール3の予
熱時図示しない偏心カムなどの移動手段により定着ロー
ル1側へ移動されて、定着ロール1へ圧接されるように
なっている。
On the other hand, the fixing roll 1 and the pressure roll 3 are rotatably supported by a frame via bearings (not shown), and the pressure roll 3 is movable in the direction toward and away from the fixing roll 1. During fixing and preheating of the pressure roll 3, it is moved toward the fixing roll 1 by a moving means such as an eccentric cam (not shown) and is brought into pressure contact with the fixing roll 1.

また定着ロール1は図示しない駆動系により矢印方向へ
回転されるようになっており、加圧ロール3は定着ロー
ル1と接触状態にあるときニノミ、加熱ロール1の回転
に伴い従動回転するようになっていると共に、加圧ロー
ル3の近傍には、加圧ロール3の外径を検出する検出手
段7が設置されている。
The fixing roll 1 is rotated in the direction of the arrow by a drive system (not shown), and the pressure roll 3 is rotated as the heating roll 1 rotates when it is in contact with the fixing roll 1. In addition, a detection means 7 for detecting the outer diameter of the pressure roll 3 is installed near the pressure roll 3.

上記径検出手段7は加圧口〜ル3が定着位置(第2図実
線位If )及び待機位置(第2図仮想線)にあるとき
、ともに依する位置に圧縮ばね8で加圧ロール3側へ付
勢された検出レバ9が設けられている。上記検出レバ9
の下部は、ガイドロール10により上記加圧ロール3の
径の増減方向に移動自在に支承されたガイド杆11の一
端が固着されていると共に、ガイド杆11の他端はポテ
ンショメータなどの位置検出器12に接続されていて、
上記検出レバ9により加圧ロール3の径の増減を電気的
に検出するようになっている。
When the pressure roller 3 is in the fixing position (solid line If in FIG. 2) and the standby position (phantom line in FIG. 2), the diameter detection means 7 is connected to the pressure roll 3 by a compression spring 8 in a dependent position. A detection lever 9 biased toward the side is provided. The above detection lever 9
One end of a guide rod 11 supported by a guide roll 10 so as to be movable in the direction of increasing and decreasing the diameter of the pressure roll 3 is fixed to the lower part of the guide rod 11, and the other end of the guide rod 11 is fixed to a position detector such as a potentiometer. It is connected to 12,
The detection lever 9 electrically detects an increase or decrease in the diameter of the pressure roll 3.

また上記位置検出器I2の出力は、加圧ロール3の僅か
な偏心による影替を取くため、時定数が30〜60秒程
夏の比較的大きな時定数を有する積分回路を介して制御
回路(ともに図示せず)へと入力され、制御回路で予め
設定された基準電圧と比較されるようになっている。制
御回路の出力側には前記移動手段が接続されていて、位
置検出器12で検出された値が基準電圧より低い場合は
移動手段により加圧口〜ル3を定着ロール1側へ移動し
て両者を圧着させ、また基準電圧より高い場合は加圧ロ
ール3を定着ロール1より離間させるようになっている
In addition, in order to compensate for the influence caused by slight eccentricity of the pressure roll 3, the output of the position detector I2 is transmitted to the control circuit via an integrating circuit having a relatively large time constant of about 30 to 60 seconds. (both not shown) and is compared with a reference voltage set in advance by a control circuit. The moving means is connected to the output side of the control circuit, and when the value detected by the position detector 12 is lower than the reference voltage, the moving means moves the pressurizing port 3 toward the fixing roll 1 side. Both are pressed together, and when the voltage is higher than a reference voltage, the pressure roll 3 is separated from the fixing roll 1.

なお用紙4の定着時には、位置検出器12の検出電流が
基準電流より大きい場合でも、加圧ロール3は定着ロー
ル1より離間せず、定着に必要なニップ幅及びニップ圧
を維持するようになっている。
Note that when fixing the paper 4, even if the current detected by the position detector 12 is larger than the reference current, the pressure roll 3 does not move away from the fixing roll 1, and the nip width and nip pressure necessary for fixing are maintained. ing.

また図中13は定着ロール1より離間して加圧ロール2
と接して加圧ロール2を回転させる駆動ロールを示す。
In addition, 13 in the figure is a pressure roll 2 spaced apart from the fixing roll 1.
2 shows a drive roll that rotates the pressure roll 2 in contact with the pressure roll 2.

一方第4図は定着ロール1側を偏心カムなどの移動手段
により加圧ロール3に対して接離移動自在とした別の実
施例を示すもので、加圧ロール3の外径を検出する位置
検出器12に歪ゲージが用いられている。上記歪ゲージ
は加圧ロール3に先端が接する弾性板14に取付けられ
ていて、加圧ロール3の外径の変化により弾性板14に
歪が生じるのを電気的に検出するようにしたものである
On the other hand, FIG. 4 shows another embodiment in which the fixing roll 1 side can be moved toward and away from the pressure roll 3 by a moving means such as an eccentric cam, and the position at which the outer diameter of the pressure roll 3 is detected is shown. A strain gauge is used as the detector 12. The strain gauge described above is attached to an elastic plate 14 whose tip is in contact with the pressure roll 3, and is designed to electrically detect strain produced in the elastic plate 14 due to a change in the outer diameter of the pressure roll 3. be.

また加圧ロール3の外径変化を検出する手段としては、
上記実施例の他、光学的な検出器を用いたり、加圧ロー
ル3の径の増加に応じて、定着ロール1及び加圧ロール
3の軸間距離を変化させて常に一定したニップ幅が得ら
れるようにしてもよい。さらに加圧ロール3内に熱源を
設けて、加圧ロール3が早期に所定の径に達するように
してもよいものである。
Further, as a means for detecting a change in the outer diameter of the pressure roll 3,
In addition to the above embodiments, a constant nip width can be obtained by using an optical detector or by changing the distance between the axes of the fixing roll 1 and the pressure roll 3 according to the increase in the diameter of the pressure roll 3. It may be possible to do so. Furthermore, a heat source may be provided in the pressure roll 3 so that the pressure roll 3 reaches a predetermined diameter quickly.

発明の効果 この発明は以上詳述したように、加圧ロールの外径を検
出する検出手段を設けて、この検出手段により検出され
た加圧ロールの外径値が所定の値に達していない場合、
加圧ロールを定着ロールに圧接させて所定の外径になる
まで嵌触回転させるようにしたことから、複写時所定の
径に達した定着ロールで定着すべき用紙を定着ロールに
圧着させながらトナー像を用紙へ熱定着することができ
、常に安定した定着が行なえるようになる。
Effects of the Invention As detailed above, this invention provides a detection means for detecting the outer diameter of the pressure roll, and detects when the outer diameter value of the pressure roll detected by the detection means does not reach a predetermined value. case,
Since the pressure roll is brought into pressure contact with the fixing roll and rotated until it reaches a predetermined outer diameter, the paper to be fixed is pressed against the fixing roll when the fixing roll reaches a predetermined diameter during copying, and the toner is transferred to the fixing roll. Images can be thermally fixed onto paper, ensuring stable fixation at all times.

【図面の簡単な説明】[Brief explanation of the drawing]

図面はこの発明の一実施例を示し、第1図は断面図、第
2図は定着ロールの外径検出手段を示す側面図、第3図
は加圧ロール部分の正面図、第4図は他の実施例を示す
説明図、第5図は従来の説明図である。 1は定着ロール、2はヒータ、3は加圧ロール、4は用
紙、7は検出手段。
The drawings show an embodiment of the present invention; FIG. 1 is a sectional view, FIG. 2 is a side view showing the outer diameter detection means of the fixing roll, FIG. 3 is a front view of the pressure roll portion, and FIG. 4 is a cross-sectional view. An explanatory diagram showing another embodiment, FIG. 5 is a conventional explanatory diagram. 1 is a fixing roll, 2 is a heater, 3 is a pressure roll, 4 is paper, and 7 is a detection means.

Claims (1)

【特許請求の範囲】[Claims] ヒータ2を内装した定着ロール1に加圧ロール3により
定着すべき用紙4を圧着して、用紙4上のトナー像を用
紙4へ熱定着するものにおいて、上記加圧ロール3の近
傍に該加圧ロール3の外径を検出する検出手段7を設け
ると共に、上記検出手段7で検出した加圧ロール3の外
径値が基準値より小さい場合、定着ロール1に加圧ロー
ル3を圧着させて基準値となるまで両ロール1、3を接
触回転させるようにしてなる電子複写機の定着装置。
A sheet of paper 4 to be fixed is pressed onto a fixing roll 1 equipped with a heater 2 by a pressure roll 3, and the toner image on the paper 4 is thermally fixed onto the paper 4. A detection means 7 for detecting the outer diameter of the pressure roll 3 is provided, and when the outer diameter value of the pressure roll 3 detected by the detection means 7 is smaller than a reference value, the pressure roll 3 is pressed against the fixing roll 1. A fixing device for an electronic copying machine that rotates both rolls 1 and 3 in contact with each other until a reference value is reached.
JP5248685A 1985-03-18 1985-03-18 Fixing device for electronic copying machine Pending JPS61212873A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5248685A JPS61212873A (en) 1985-03-18 1985-03-18 Fixing device for electronic copying machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5248685A JPS61212873A (en) 1985-03-18 1985-03-18 Fixing device for electronic copying machine

Publications (1)

Publication Number Publication Date
JPS61212873A true JPS61212873A (en) 1986-09-20

Family

ID=12916042

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5248685A Pending JPS61212873A (en) 1985-03-18 1985-03-18 Fixing device for electronic copying machine

Country Status (1)

Country Link
JP (1) JPS61212873A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0441351A2 (en) * 1990-02-07 1991-08-14 Canon Kabushiki Kaisha Image forming device
US5264902A (en) * 1990-02-07 1993-11-23 Canon Kabushiki Kaisha Image forming device
JP2006259738A (en) * 2005-03-16 2006-09-28 Toshiba Corp Fixing apparatus and image forming apparatus
JP2011186395A (en) * 2010-03-11 2011-09-22 Ricoh Co Ltd Fixing device, image forming apparatus, and method of controlling fixing device
JP2011191376A (en) * 2010-03-12 2011-09-29 Ricoh Co Ltd Fixing device and image-forming device
JP2011257535A (en) * 2010-06-08 2011-12-22 Ricoh Co Ltd Fixing device and image forming apparatus using the same

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0441351A2 (en) * 1990-02-07 1991-08-14 Canon Kabushiki Kaisha Image forming device
US5264902A (en) * 1990-02-07 1993-11-23 Canon Kabushiki Kaisha Image forming device
JP2006259738A (en) * 2005-03-16 2006-09-28 Toshiba Corp Fixing apparatus and image forming apparatus
JP2011186395A (en) * 2010-03-11 2011-09-22 Ricoh Co Ltd Fixing device, image forming apparatus, and method of controlling fixing device
JP2011191376A (en) * 2010-03-12 2011-09-29 Ricoh Co Ltd Fixing device and image-forming device
JP2011257535A (en) * 2010-06-08 2011-12-22 Ricoh Co Ltd Fixing device and image forming apparatus using the same

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