JP3373658B2 - Transfer device and transfer material neutralization device - Google Patents

Transfer device and transfer material neutralization device

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Publication number
JP3373658B2
JP3373658B2 JP15760094A JP15760094A JP3373658B2 JP 3373658 B2 JP3373658 B2 JP 3373658B2 JP 15760094 A JP15760094 A JP 15760094A JP 15760094 A JP15760094 A JP 15760094A JP 3373658 B2 JP3373658 B2 JP 3373658B2
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JP
Japan
Prior art keywords
transfer
image
transfer material
static elimination
bias
Prior art date
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Expired - Fee Related
Application number
JP15760094A
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Japanese (ja)
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JPH0822204A (en
Inventor
克哉 川越
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Ricoh Co Ltd
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Ricoh Co Ltd
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Priority to JP15760094A priority Critical patent/JP3373658B2/en
Publication of JPH0822204A publication Critical patent/JPH0822204A/en
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Publication of JP3373658B2 publication Critical patent/JP3373658B2/en
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Expired - Fee Related legal-status Critical Current

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Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は複写機，ファクシミリ，
プリンタ等の画像形成装置における転写装置及び転写材
除電装置に関する。The present invention relates to a copying machine, a facsimile,
The present invention relates to a transfer device and a transfer material charge eliminating device in an image forming apparatus such as a printer.

【０００２】[0002]

【従来の技術】複写機，ファクシミリ，プリンタ等の画
像形成装置は、一般に、感光体等からなる像担持体の表
面にトナー像を形成してこのトナー像を転写装置により
転写材に転写し、この転写材をトナー像転写後に転写材
除電装置により除電して像担持体から分離している。上
記転写装置は、コロナ放電器に所定の電圧を印加し、こ
のコロナ放電器により転写材の背面側から像担持体側に
向けてコロナ放電を行って像担持体表面のトナー像を転
写材の表面に転写するコロナ転写装置や、転写ローラに
所定の転写バイアス電圧を印加して転写材が像担持体と
転写ローラとの間を通過する際に像担持体表面のトナー
像を転写材の表面に転写するローラ転写装置などがあ
る。2. Description of the Related Art Generally, an image forming apparatus such as a copying machine, a facsimile or a printer forms a toner image on the surface of an image bearing member such as a photosensitive member and transfers the toner image onto a transfer material by a transfer device. After the transfer of the toner image on the transfer material, the transfer material is removed by a charge removing device to separate the transfer material from the image carrier. The transfer device applies a predetermined voltage to a corona discharger, and performs corona discharge from the back side of the transfer material toward the image carrier side by the corona discharger to transfer the toner image on the surface of the image carrier to the surface of the transfer material. When a transfer material passes between the image carrier and the transfer roller by applying a predetermined transfer bias voltage to the corona transfer device or the transfer roller, the toner image on the surface of the image carrier is transferred to the surface of the transfer material. There is a roller transfer device for transferring.

【０００３】これらの転写装置では、コロナ放電器や転
写ローラに対する電圧印加は、転写材が像担持体とコロ
ナ放電器や転写ローラとの間にある時にのみ行ってお
り、像担持体に対して不要な電圧印加を行わないよう
に、また、オゾンを発生しないようにタイミングをとっ
ているものが多い。また、特開平１ー１３６１８０号公
報には、転写材搬送タイミングの誤差により転写バイア
ス電圧印加タイミングがずれることを防ぐために、感光
体上のトナー像を転写ローラを用いて記録紙に転写する
電子写真記録装置において、記録すべき画像信号を検出
する手段により、記録信号の有無に応じて転写ローラに
転写バイアス電圧を印加するようにしたことを特徴とす
る転写制御法が記載されている。In these transfer apparatuses, the voltage application to the corona discharger or the transfer roller is performed only when the transfer material is between the image carrier and the corona discharger or the transfer roller, and the voltage is applied to the image carrier. In many cases, timing is set so that unnecessary voltage is not applied and ozone is not generated. Further, in Japanese Patent Application Laid-Open No. 1-136180, in order to prevent the transfer bias voltage application timing from being deviated due to an error in the transfer material conveyance timing, an electrophotographic image in which a toner image on a photoconductor is transferred onto a recording sheet by using a transfer roller. In a recording apparatus, a transfer control method is described in which a transfer bias voltage is applied to a transfer roller according to the presence or absence of a recording signal by means of detecting an image signal to be recorded.

【０００４】特開平２ー３２３８５号公報には、像担持
体上に形成されたトナー像をコロナ放電器から前記像担
持体に向けて放出されるコロナイオンを利用して転写材
に転写する画像形成装置において、前記転写材のサイズ
及び／又は材質を検知する検知手段と、前記検知手段の
検知情報に応じて前記コロナ放電器の前記像担持体に放
出するコロナイオン電流を予め設定された最適値に制御
する制御手段とを備え、前記コロナイオン電流の内の前
記転写材に流れる電流をサイズ及び／又は材質に拘らず
略一定に制御することを特徴とする画像形成装置が記載
されている。In JP-A-2-32385, an image in which a toner image formed on an image carrier is transferred to a transfer material by using corona ions emitted from a corona discharge device toward the image carrier. In the forming apparatus, a detection unit that detects the size and / or the material of the transfer material, and an optimum preset corona ion current to be emitted to the image carrier of the corona discharger according to the detection information of the detection unit. An image forming apparatus is described, which comprises a control unit for controlling the value to a value, and controls a current of the corona ion current flowing through the transfer material to be substantially constant regardless of size and / or material. .

【０００５】特開平４ー３３６５７６号公報には、少な
くとも導電性を有する弾性部材からなる転写ローラの導
電層を軸方向に電気的に独立した複数の領域に分割し、
紙幅検出器により記録紙の紙幅方向ガイドの位置を検出
してこの紙幅検出器の検出結果から記録紙幅に応じてバ
イアス制御装置により上記複数の領域への転写バイアス
印加と印加量制御とを行うようにした転写装置が記載さ
れている。In Japanese Patent Laid-Open No. 4-336576, a conductive layer of a transfer roller made of at least a conductive elastic member is divided into a plurality of axially independent regions.
The paper width detector detects the position of the guide in the paper width direction of the recording paper, and based on the detection result of the paper width detector, the bias control device controls the application of the transfer bias and the application amount to the plurality of areas according to the recording paper width. Described transfer device.

【０００６】また、上記転写材除電装置は、コロナ除電
装置等に電圧を印加して該コロナ除電装置等により転写
材をトナー像転写後に除電し、異常画像の防止や転写材
分離性の向上を計っている。そして、コロナ除電装置で
は、転写材の除電は、転写材が像担持体とコロナ除電装
置との間にある時にのみ行っており、像担持体に対して
不要な電圧印加を行わないように、また、余分なオゾン
を発生しないようにタイミングをとっているものが多
い。Further, in the above-mentioned transfer material static eliminator, a voltage is applied to a corona static eliminator or the like to charge the transfer material after transferring the toner image by the corona static eliminator or the like, thereby preventing abnormal images and improving transfer material separability. I am measuring. Then, in the corona charge eliminator, charge elimination of the transfer material is performed only when the transfer material is between the image carrier and the corona charge eliminator, so as not to apply unnecessary voltage to the image carrier, In addition, many of them are timed so as not to generate excess ozone.

【０００７】特開昭６１ー１６２０７３号公報には、感
光体を帯電手段、像露光手段、現像手段、転写コロナ発
生手段および分離手段の各部位を順次通過移動せしめ、
該感光体上に形成されたトナー粒子の現像像を該感光体
に密着して同期的に移送される転写材上に転写し、該転
写後の転写材を前記感光体より分離するようにした電子
写真装置において、前記分離手段は、前記感光体との間
に所要の間隙を保持して配置された絶縁体ブロックに先
端が突出しないように取り付けられた除電針からなる除
電器であり、該除電器の除電針には、前記転写コロナ発
生手段と共通に用いる同一電源により該コロナ発生手段
に印加される電圧とは逆極性の成分を含む電圧を印加
し、該印加電圧を前記除電針が自己放電を開始する電圧
よりも低くしたことを特徴とする電子写真装置における
転写材分離装置が記載されている。In Japanese Patent Laid-Open No. 61-162073, a photosensitive member is moved sequentially through respective portions of a charging means, an image exposing means, a developing means, a transfer corona generating means and a separating means.
The developed image of the toner particles formed on the photoconductor is transferred onto a transfer material that is in close contact with the photoconductor and is transferred synchronously, and the transfer material after the transfer is separated from the photoconductor. In the electrophotographic apparatus, the separating unit is a static eliminator including a static elimination needle attached to an insulator block arranged so as to maintain a required gap between the photoconductor and the tip so as not to project, A voltage including a component having a polarity opposite to the voltage applied to the corona generating means is applied to the charge removing needle of the static eliminator by the same power source used in common with the transfer corona generating means, and the applied voltage is applied to the charge eliminating needle by the charge removing needle. There is described a transfer material separating device in an electrophotographic device, which is characterized in that the voltage is lower than the voltage at which self-discharge is started.

【０００８】[0008]

【発明が解決しようとする課題】上記転写装置では、コ
ロナ放電器や転写ローラに対する電圧印加は転写材が像
担持体とコロナ放電器や転写ローラとの間にある時にの
み行っているが、コロナ放電器や転写ローラへの電圧印
加を最適に行うことができなくて転写材の必要の無い部
分に対して過剰に行うので、余分な電力を消費し、ま
た、コロナ転写装置では余分なオゾンを発生する。ま
た、上記転写材除電装置では、転写材の除電は転写材が
像担持体とコロナ除電装置との間にある時にのみ行って
いるが、転写材除電装置への電圧印加を最適に行うこと
ができなくて転写材の必要の無い部分に対して過剰に行
うので、余分な電力消費や、過剰な電圧印加による像担
持体の疲労，抵抗低下及び異常画像が生じ、また、コロ
ナ除電装置では余分なオゾンを発生する。In the above transfer device, the voltage is applied to the corona discharger or the transfer roller only when the transfer material is between the image carrier and the corona discharger or the transfer roller. Since the voltage cannot be optimally applied to the discharger or transfer roller and it is applied excessively to unnecessary parts of the transfer material, extra power is consumed and extra ozone is used in the corona transfer device. Occur. Further, in the above-mentioned transfer material charge eliminating device, charge removal of the transfer material is performed only when the transfer material is between the image carrier and the corona charge eliminating device, but it is possible to optimally apply voltage to the transfer material charge eliminating device. Since it is performed excessively on the unnecessary portion of the transfer material, excessive power consumption, fatigue of the image bearing member due to excessive voltage application, resistance decrease and abnormal images occur. Generates ozone.

【０００９】本発明は、上記問題点を改善し、最適な電
圧印加を行うことができて余分な電力消費や過剰な電圧
印加による像担持体の疲労，抵抗低下及び異常画像、余
分なオゾン発生の防止、転写材分離性の向上を計ること
ができる転写装置及び転写材除電装置を提供することを
目的とする。The present invention solves the above problems and enables optimum voltage application, resulting in fatigue of the image carrier due to excessive power consumption and excessive voltage application, resistance reduction and abnormal images, and extra ozone generation. It is an object of the present invention to provide a transfer device and a transfer material static eliminator that can prevent the above phenomenon and improve the transfer material separability.

【００１０】[0010]

【課題を解決するための手段】上記目的を達成するた
め、請求項１記載の発明は、像担持体の表面にトナー像
を形成してこのトナー像を転写材に転写し、この転写材
をトナー像転写後に除電する画像形成装置の転写材除電
装置において、除電バイアスが印加されて転写材を除電
する除電手段と、この除電手段に対して少なくとも２つ
以上の異なる除電バイアスを転写材幅方向位置に応じて
同時に印加する除電バイアス印加手段とを備えたもので
ある。To achieve the above object, the invention according to claim 1 provides a toner image on the surface of an image carrier.
And transfer this toner image to a transfer material.
Of the transfer material of the image forming device that removes the charge after transferring the toner image
In the device, a static elimination bias is applied to neutralize the transfer material.
Static elimination means and at least two for this static elimination means
Depending on the position of the transfer material width direction
It is provided with a discharging bias applying means for simultaneously applying .

【００１１】請求項２記載の発明は、請求項１記載の転
写装置において、記録すべき画像信号を検出する画像信
号検出手段の検出結果により、画像信号に応じて除電バ
イアスの電圧値と印加位置を決定する手段を備えたもの
である。The invention of claim 2 is the same as that of claim 1.
The image signal for detecting the image signal to be recorded in the copying device.
According to the detection result of the signal detection means, the static elimination
It is provided with a means for determining the voltage value of the bias and the application position .

【００１２】請求項３記載の発明は、像担持体の表面に
トナー像を形成してこのトナー像を転写材に転写し、こ
の転写材をトナー像転写後に除電する画像形成装置にお
ける転写材除電装置において、のこ歯状若しくは針状に
形成されて転写材幅方向に複数に分割され、転写材を除
電する導電板からなる除電用電極と、この除電用電極の
各分割部分にそれぞれ別々に除電バイアスを印加する除
電バイアス印加手段とを備えたものである。According to a third aspect of the invention, the surface of the image carrier is
A toner image is formed, and this toner image is transferred to a transfer material.
In the image forming device that removes the charge from the transfer material after transferring the toner image.
In the transfer material static eliminator,
The transfer material is formed and divided into multiple pieces in the width direction of the transfer material.
Of the static elimination electrode, which consists of a conductive plate
Static elimination bias is applied to each divided part separately.
And an electric bias applying means .

【００１３】[0013]

【００１４】[0014]

【００１５】[0015]

【００１６】[0016]

【作用】請求項１記載の発明では、除電バイアス印加手
段が除電手段に対して少なくとも２つ以上の異なる除電
バイアスを転写材幅方向位置に応じて同時に印加し、除
電手段が転写材を除電する。 According to the first aspect of the present invention, the static elimination bias applying step is performed.
The stage has at least two different static eliminations with respect to the static elimination means.
A bias is applied at the same time according to the position in the width direction of the transfer material, and the bias is removed.
The charging means removes the charge from the transfer material.

【００１７】請求項２記載の発明では、請求項１記載の
転写装置において、記録すべき画像信号を検出する画像
信号検出手段の検出結果により、画像信号に応じて除電
バイアスの電圧値と印加位置が決定される。 According to the invention of claim 2, the invention of claim 1
Image that detects the image signal to be recorded in the transfer device
Charge removal according to the image signal by the detection result of the signal detection means
The bias voltage value and the application position are determined.

【００１８】請求項３記載の発明では、除電バイアス印
加手段が除電用電極の各分割部分にそれぞれ別々に除電
バイアスを印加し、除電用電極が転写材を除電する。 According to the third aspect of the invention, the static elimination bias mark is used.
The adding means removes charge separately to each divided part of the charge removal electrode.
A bias is applied, and the static elimination electrode neutralizes the transfer material.

【００１９】[0019]

【００２０】[0020]

【００２１】[0021]

【００２２】[0022]

【実施例】図１は請求項１〜３記載の発明を適用した画
像形成装置の第１の例を示し、図２はその一部を示す。
この第１の例は、複写機からなる電子写真方式の画像形
成装置の例であり、像担持体として感光体ドラム１１が
用いられている。画像形成動作時には、原稿画素は画像
検知板からなる原稿読み取り手段１２により検知され、
時系列の画像信号に変換される。この原稿読み取り手段
１２からの画像信号は画像処理装置１３により所定の画
像処理がなされて露光手段を構成するレーザ発光源１４
へ出力される。レーザ発光源１４は、画像処理装置１３
からの画像信号により駆動され、画像信号により強度変
調されたレーザ光を出射する。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a first example of an image forming apparatus to which the invention described in claims 1 to 3 is applied, and FIG. 2 shows a part thereof.
The first example is an example of an electrophotographic image forming apparatus including a copying machine, in which a photosensitive drum 11 is used as an image carrier. During the image forming operation, the document pixels are detected by the document reading unit 12 including an image detection plate,
It is converted into a time series image signal. The image signal from the document reading means 12 is subjected to a predetermined image processing by an image processing device 13 and a laser emission source 14 constituting an exposing means.
Is output to. The laser emission source 14 is the image processing device 13.
It is driven by the image signal from and emits a laser beam whose intensity is modulated by the image signal.

【００２３】また、感光体ドラム１１はモータにより回
転駆動されて帯電手段たる帯電チャージャ１５により均
一に帯電され、レーザ発光源１４からのレーザ光は偏向
器により偏向されて光学系により感光体ドラム１１に結
像されることにより感光体ドラム１１に画像露光がなさ
れて静電潜像が形成される。この感光体ドラム１１上の
静電潜像は現像装置１６により現像されてトナー像とな
り、給紙装置から給送されてきた転写紙からなる転写材
は転写装置１７により感光体ドラム１１上のトナー像が
転写された後に分離手段により感光体ドラム１１から分
離されて定着装置によりトナー像が定着される。また、
感光体ドラム１１は、転写紙分離後にクリーニング装置
１８によりクリーニングされて残留トナーが除去され、
次の画像形成動作に備える。Further, the photosensitive drum 11 is rotationally driven by a motor and is uniformly charged by a charging charger 15 as a charging means, and the laser light from the laser emission source 14 is deflected by a deflector and the photosensitive drum 11 by an optical system. By forming an image on the photosensitive drum 11, an image is exposed on the photosensitive drum 11 to form an electrostatic latent image. The electrostatic latent image on the photosensitive drum 11 is developed into a toner image by the developing device 16, and the transfer material composed of the transfer paper fed from the paper feeding device is transferred onto the photosensitive drum 11 by the transfer device 17. After the image is transferred, it is separated from the photoconductor drum 11 by the separating means and the toner image is fixed by the fixing device. Also,
The photosensitive drum 11 is cleaned by the cleaning device 18 after the transfer paper is separated to remove the residual toner,
Prepare for the next image forming operation.

【００２４】転写装置１７は感光体ドラム１１側に開口
部を有する遮蔽枠１９内にのこ歯状（若しくは針状）に
形成された導電板からなる転写用電極２０を配置した転
写手段を備えたコロナ転写装置であり、転写用電極２０
は転写紙が感光体ドラム１１と転写用電極２０との間を
通過する時に電源２１〜２３からスウィッチング回路２
４を介して転写バイアス電圧が印加されることにより転
写紙の背面側から感光体ドラム１１に向けてコロナ放電
を行って感光体ドラム１１上のトナー像を転写紙に転写
させる。The transfer device 17 is equipped with a transfer means in which a transfer electrode 20 made of a conductive plate formed in a sawtooth shape (or a needle shape) is arranged in a shield frame 19 having an opening on the side of the photosensitive drum 11. It is a corona transfer device, and the transfer electrode 20
Is a switching circuit 2 from the power sources 21 to 23 when the transfer paper passes between the photoconductor drum 11 and the transfer electrode 20.
A transfer bias voltage is applied via 4 to perform corona discharge from the back side of the transfer paper toward the photoconductor drum 11 to transfer the toner image on the photoconductor drum 11 to the transfer paper.

【００２５】導電板２０は感光体ドラム１１と対向して
転写紙幅方向（転写紙搬送方向と直角な方向）と平行に
配置される。この導電板２０は転写紙幅方向へ所定の長
さ（例えば一定の長さ）毎に分割されて複数の部分Ａ，
Ｂ，Ｃ・・・Ｊに分割され、これらの部分Ａ〜Ｊはそれ
ぞれスウィッチング回路２４により互いに独立して互い
に異なる少なくとも２種類以上の転写バイアス電圧、例
えば互いに異なる３種類の電圧Ｖ1，Ｖ2，Ｖ3が電源２
１〜２３から選択的に印加される。従って、スウィッチ
ング回路２４及び電源２１〜２３は導電板２０の各部分
Ａ，Ｂ，Ｃ・・・Ｊにそれぞれ転写バイアスを印加する
転写バイアス印加手段を構成する。The conductive plate 20 faces the photoconductor drum 11 and is arranged in parallel with the width direction of the transfer paper (direction perpendicular to the transfer paper transport direction). The conductive plate 20 is divided into a plurality of parts A, each having a predetermined length (for example, a fixed length) in the transfer paper width direction.
The parts A to J are divided into B, C, ... J, and these parts A to J are each independently separated by the switching circuit 24 from at least two types of transfer bias voltages different from each other, for example, three types of voltages V 1 and V different from each other. 2 , V 3 is power supply 2
1 to 23 are selectively applied. Therefore, the switching circuit 24 and the power supplies 21 to 23 constitute transfer bias applying means for applying the transfer bias to the respective portions A, B, C, ... J of the conductive plate 20.

【００２６】図１に示すように画像記憶演算装置２５は
画像処理装置１３からの画像信号を一旦メモリに記憶す
る。また、画像記憶演算装置２５は、記録すべき画像信
号（記録すべき画素の信号）を検出する画像信号検出手
段を兼ね、図２に示すように転写紙２６を転写用電極２
０の各部分Ａ〜Ｊに対応して転写紙幅方向へ複数に分割
すると共に転写紙搬送方向に複数に所定の長さ（例えば
一定の長さ）毎に分割することにより、複数の領域０Ａ
〜０Ｊ，１Ａ〜１Ｊ，２Ａ〜２Ｊ・・・ｎＡ〜ｎＪに分
割し、上記メモリに記憶した画像信号から転写紙２６の
各領域０Ａ〜ｎＪに転写される画像の面積率（画像部の
全体に対する面積率）ｓを求める。As shown in FIG. 1, the image storage / calculation device 25 temporarily stores the image signal from the image processing device 13 in the memory. Further, the image storage / calculation device 25 also serves as an image signal detecting means for detecting an image signal to be recorded (a signal of a pixel to be recorded), and as shown in FIG.
A plurality of areas 0A are obtained by dividing the transfer paper in the transfer paper width direction into a plurality of areas A to J corresponding to 0 and dividing the transfer paper in the transfer paper conveyance direction into a plurality of predetermined lengths (for example, constant lengths).
..0J, 1A to 1J, 2A to 2J ... nA to nJ, and the area ratio of the image transferred to the respective areas 0A to nJ of the transfer paper 26 from the image signal stored in the memory (the entire image portion Area ratio) s is calculated.

【００２７】そして、画像記憶演算装置２５は、転写紙
２６の各領域毎の画像面積率ｓから転写用電極２０の各
部分Ａ〜Ｊに印加する転写バイアス電圧を決定し、例え
ば０≦ｓ＜３０％の時は転写バイアス電圧をＶ1に決定
し、３０％≦ｓ＜６５％の時は転写バイアス電圧をＶ2
に決定し、６５％≦ｓ≦１００％の時は転写バイアス電
圧をＶ3に決定し、これらの決定した転写バイアス電圧
を転写紙２６の各領域が転写位置を通過する時にスウィ
ッチング回路２４に指示する信号を出力する。Then, the image storage / calculation device 25 determines the transfer bias voltage to be applied to each of the portions A to J of the transfer electrode 20 from the image area ratio s of each region of the transfer paper 26, for example, 0 ≦ s < The transfer bias voltage is determined to be V 1 when 30%, and the transfer bias voltage is V 2 when 30% ≦ s <65%.
When 65% ≦ s ≦ 100%, the transfer bias voltage is determined to V 3, and the determined transfer bias voltage is applied to the switching circuit 24 when each region of the transfer paper 26 passes the transfer position. Output the signal to instruct.

【００２８】スウィッチング回路２４は転写用電極２０
の各部分Ａ〜Ｊに対してそれぞれ電源２１〜２３からの
３種類の転写バイアス電圧Ｖ1，Ｖ2，Ｖ3を画像記憶演
算装置２５の指示に従って印加する。すなわち、スウィ
ッチング回路２４は、転写紙２６の幅方向へ一列に配列
された領域０Ａ〜０Ｊが転写用電極２０と感光体ドラム
１１との間の転写位置を通過する時ｔ0には転写用電極
２０の各部分Ａ〜Ｊに対してそれぞれ電源２１〜２３か
らの３種類の転写バイアス電圧Ｖ1，Ｖ2，Ｖ3を転写紙
２６の各領域０Ａ〜０Ｊの画像面積率に応じて印加し、
転写紙２６の幅方向へ一列に配列された領域１Ａ〜１Ｊ
が転写用電極２０と感光体ドラム１１との間の転写位置
を通過する時ｔ1には転写用電極２０の各部分Ａ〜Ｊに
対してそれぞれ電源２１〜２３からの３種類の転写バイ
アス電圧Ｖ1，Ｖ2，Ｖ3を転写紙２６の各領域１Ａ〜１
Ｊの画像面積率に応じて印加し、転写紙２６の幅方向へ
一列に配列された部分２Ａ〜２Ｊが転写用電極２０と感
光体ドラム１１との間の転写位置を通過する時ｔ2には
転写用電極２０の各部分Ａ〜Ｊに対してそれぞれ電源２
１〜２３からの３種類の転写バイアス電圧Ｖ1，Ｖ2，Ｖ
3を転写紙２６の各領域２Ａ〜２Ｊの画像面積率に応じ
て印加するというように転写用電極２０の各部分Ａ〜Ｊ
に対してそれぞれ電源２１〜２３からの３種類の転写バ
イアス電圧Ｖ1，Ｖ2，Ｖ3を画像記憶演算装置２５の指
示に従って印加する。The switching circuit 24 is used for the transfer electrode 20.
Three types of transfer bias voltages V 1 , V 2 and V 3 from the power sources 21 to 23 are applied to the respective portions A to J in accordance with the instruction of the image storage arithmetic unit 25. That is, switchgrass ring circuit 24, for transfer to the t 0 when regions 0A~0J arranged in a row in the width direction of the transfer sheet 26 passes through the transfer position between the photosensitive drum 11 and the transfer electrode 20 Three types of transfer bias voltages V 1 , V 2 , and V 3 from power sources 21 to 23 are applied to the respective portions A to J of the electrode 20 in accordance with the image area ratios of the regions 0A to 0J of the transfer paper 26. Then
Areas 1A to 1J arranged in a line in the width direction of the transfer paper 26
When passing through the transfer position between the transfer electrode 20 and the photoconductor drum 11, three kinds of transfer bias voltages from the power sources 21 to 23 are supplied to the respective portions A to J of the transfer electrode 20 at t 1. each region of V 1, V 2, V 3 the transfer sheet 26 1A～1
J is applied in accordance with the image area ratio, and when the portions 2A to 2J arranged in a line in the width direction of the transfer paper 26 pass the transfer position between the transfer electrode 20 and the photosensitive drum 11, at t 2 . Is a power source 2 for each part A to J of the transfer electrode 20.
Three types of transfer bias voltages V 1 , V 2 , V from 1 to 23
3 is applied according to the image area ratio of each area 2A to 2J of the transfer paper 26, and each portion A to J of the transfer electrode 20 is applied.
3 types of transfer bias voltages V 1 , V 2 , and V 3 from the power sources 21 to 23 are applied according to the instructions of the image storage arithmetic unit 25.

【００２９】例えば、スウィッチング回路２４は、転写
紙２６の幅方向へ一列に配列された領域１Ａ〜１Ｊが転
写用電極２０と感光体ドラム１１との間の転写位置を通
過する時ｔ1には、転写紙２６の領域１Ｂの画像面積率
ｓ1Bがｓ1B＝２０％であれば電源２１からの転写バイア
ス電圧Ｖ1を転写用電極２０の分割部分Ｂに印加し、転
写紙２６の領域１Ｃの画像面積率ｓ1Cがｓ1C＝３２％で
あれば電源２２からの転写バイアス電圧Ｖ2を転写用電
極２０の分割部分Ｃに印加し、転写紙２６の領域１Ｄの
画像面積率ｓ1Dがｓ1D＝５０％であれば電源２２からの
転写バイアス電圧Ｖ2を転写用電極２０の分割部分Ｄに
印加し、転写紙２６の領域１Ｅの画像面積率ｓ1Eがｓ1E
＝７０％であれば電源２３からの転写バイアス電圧Ｖ3
を転写用電極２０の分割部分Ｅに印加する。For example, the switching circuit 24 operates at time t 1 when the areas 1A to 1J arranged in a line in the width direction of the transfer paper 26 pass the transfer position between the transfer electrode 20 and the photosensitive drum 11. When the image area ratio s 1B of the area 1B of the transfer paper 26 is s 1B = 20%, the transfer bias voltage V 1 from the power source 21 is applied to the divided portion B of the transfer electrode 20 to obtain the area of the transfer paper 26. If the image area ratio s 1C of 1C is s 1C = 32%, the transfer bias voltage V 2 from the power source 22 is applied to the divided portion C of the transfer electrode 20, and the image area ratio s 1D of the area 1D of the transfer paper 26 is applied. Is s 1D = 50%, the transfer bias voltage V 2 from the power source 22 is applied to the divided portion D of the transfer electrode 20, and the image area ratio s 1E of the region 1E of the transfer paper 26 is s 1E.
= 70%, the transfer bias voltage V 3 from the power source 23
Is applied to the divided portion E of the transfer electrode 20.

【００３０】この第１の例では、転写用電極２０の各部
分Ａ〜Ｊに対して複数種類の転写バイアスを転写紙幅方
向位置に応じて同時に印加するので、転写用電極２０の
各部分Ａ〜Ｊに対して最適な転写バイアス電圧を印加す
ることができ、余分な電力消費を防ぐことができる。ま
た、転写装置はコロナ放電により感光体ドラム１１上の
トナー像を転写紙に転写するコロナ転写装置であるの
で、余分なオゾン発生を防ぐことができる。In the first example, a plurality of types of transfer biases are simultaneously applied to the respective portions A to J of the transfer electrode 20 in accordance with the position in the width direction of the transfer paper, so that the respective portions A to A of the transfer electrode 20 are applied. An optimal transfer bias voltage can be applied to J, and extra power consumption can be prevented. Further, since the transfer device is a corona transfer device that transfers the toner image on the photosensitive drum 11 to the transfer paper by corona discharge, it is possible to prevent excess ozone generation.

【００３１】また、画像記憶演算装置２５は、記録すべ
き画像信号を検出する画像信号検出手段を兼ね、転写用
電極２０の各部分Ａ〜Ｊに印加する転写バイアスの電圧
値と印加位置を記録すべき画像信号に応じて決定するの
で、画像信号に応じて最適な転写バイアスを転写用電極
２０の各部分Ａ〜Ｊに印加することができ、過剰な電圧
印加による感光体ドラム１１の疲労や抵抗低下を防ぐこ
とができる。また、転写材には画像部以外に不要な電荷
を与えずに転写材の分離性を高めることができる。さら
に、転写装置はのこ歯状（若しくは針状）に形成された
導電板からなる転写用電極２０を用いて構成したので、
より簡単な構成で安価にできる。The image storage / calculation device 25 also functions as an image signal detecting means for detecting an image signal to be recorded, and records the voltage value and the application position of the transfer bias applied to each portion A to J of the transfer electrode 20. Since it is determined according to the image signal to be transferred, the optimum transfer bias can be applied to each of the portions A to J of the transfer electrode 20 according to the image signal, and fatigue of the photosensitive drum 11 due to excessive voltage application and Resistance drop can be prevented. In addition, the separability of the transfer material can be improved without giving unnecessary charges to the transfer material other than the image portion. Further, since the transfer device is configured by using the transfer electrode 20 formed of a conductive plate formed in a sawtooth shape (or a needle shape),
It can be made cheaper with a simpler configuration.

【００３２】図３は請求項４〜６記載の発明を適用した
画像形成装置の第２の例を示し、図４はその一部を示
す。この第２の例は、複写機からなる電子写真方式の画
像形成装置の例であり、像担持体として感光体ドラム１
１が用いられている。画像形成動作時には、原稿画素は
画像検知板からなる原稿読み取り手段１２により検知さ
れ、時系列の画像信号に変換される。この原稿読み取り
手段１２からの画像信号は画像処理装置１３により所定
の画像処理がなされて露光手段を構成するレーザ発光源
１４へ出力される。レーザ発光源１４は、画像処理装置
１３からの画像信号により駆動され、画像信号により強
度変調されたレーザ光を出射する。FIG. 3 shows a second example of the image forming apparatus to which the inventions of claims 4 to 6 are applied, and FIG. 4 shows a part thereof. The second example is an example of an electrophotographic image forming apparatus including a copying machine, and the photosensitive drum 1 is used as an image carrier.
1 is used. During the image forming operation, the document pixels are detected by the document reading unit 12 including an image detection plate and converted into a time-series image signal. The image signal from the document reading means 12 is subjected to predetermined image processing by the image processing device 13 and output to the laser emission source 14 which constitutes the exposing means. The laser emission source 14 is driven by the image signal from the image processing device 13 and emits laser light whose intensity is modulated by the image signal.

【００３３】また、感光体ドラム１１はモータにより回
転駆動されて帯電手段たる帯電チャージャ１５により均
一に帯電され、レーザ発光源１４からのレーザ光は偏向
器により偏向されて光学系により感光体ドラム１１に結
像されることにより感光体ドラム１１に画像露光がなさ
れて静電潜像が形成される。この感光体ドラム１１上の
静電潜像は現像装置１６により現像されてトナー像とな
り、給紙装置から給送されてきた転写紙からなる転写材
は転写装置２７により感光体ドラム１１上のトナー像が
転写された後に転写材除電装置２８による除電で感光体
ドラム１１から分離されて定着装置によりトナー像が定
着される。また、感光体ドラム１１は、転写紙分離後に
クリーニング装置１８によりクリーニングされて残留ト
ナーが除去され、次の画像形成動作に備える。転写装置
２７は、例えばコロナ転写装置が用いられ、転写紙が感
光体ドラム１１と転写装置２７との間を通過する時に転
写紙の背面からコロナ放電を行って転写紙を帯電させる
ことにより感光体ドラム１１上のトナー像を転写させ
る。Further, the photosensitive drum 11 is rotationally driven by a motor and uniformly charged by a charging charger 15 which is a charging means, and the laser light from the laser emission source 14 is deflected by a deflector and the photosensitive drum 11 by an optical system. By forming an image on the photosensitive drum 11, an image is exposed on the photosensitive drum 11 to form an electrostatic latent image. The electrostatic latent image on the photosensitive drum 11 is developed by the developing device 16 into a toner image, and the transfer material composed of transfer paper fed from the paper feeding device is transferred onto the toner on the photosensitive drum 11 by the transfer device 27. After the image is transferred, it is separated from the photoconductor drum 11 by the charge removal by the transfer material charge removal device 28, and the toner image is fixed by the fixing device. Further, the photosensitive drum 11 is cleaned by the cleaning device 18 after the transfer paper is separated to remove the residual toner, and prepares for the next image forming operation. As the transfer device 27, for example, a corona transfer device is used, and when the transfer paper passes between the photoconductor drum 11 and the transfer device 27, a corona discharge is performed from the back surface of the transfer paper to charge the transfer paper and thereby the photoconductor. The toner image on the drum 11 is transferred.

【００３４】転写材除電装置２７は転写紙搬送路側に開
口部を有する遮蔽枠２９内にのこ歯状（若しくは針状）
に形成された導電板からなる除電用電極３０を配置した
除電手段を備えたコロナ除電方式の転写材除電装置であ
り、除電用電極３０は転写紙が感光体ドラム１１と除電
用電極３０との間を通過する時に電源３１〜３３からス
ウィッチング回路３４を介して除電バイアス電圧が印加
されることにより転写紙の背面側から転写紙の背面に向
けてコロナ放電を行って転写紙を除電することにより転
写紙を感光体ドラム１１から分離させる。The transfer material static eliminator 27 has a saw-tooth shape (or a needle shape) inside a shield frame 29 having an opening on the transfer paper conveying path side.
Is a corona charge-eliminating type transfer material charge-eliminating device provided with a charge-eliminating unit having a charge-eliminating electrode 30 formed of a conductive plate formed on the transfer plate. A static electricity removing bias voltage is applied from the power sources 31 to 33 through the switching circuit 34 when passing through the space to perform corona discharge from the back side of the transfer sheet toward the back side of the transfer sheet to remove the charge from the transfer sheet. The transfer paper is separated from the photoconductor drum 11 by.

【００３５】導電板３０は転写紙搬送路と対向して転写
紙幅方向（転写紙搬送方向と直角な方向）と平行に配置
される。この導電板３０は転写紙幅方向へ所定の長さ
（例えば一定の長さ）毎に分割されて複数の部分Ａ，
Ｂ，Ｃ・・・Ｊに分割され、これらの部分Ａ〜Ｊはそれ
ぞれスウィッチング回路３４により互いに独立して互い
に異なる少なくとも２種類以上の除電バイアス電圧、例
えば互いに異なる３種類の電圧Ｖ1，Ｖ2，Ｖ3が電源３
１〜３３から選択的に印加される。従って、スウィッチ
ング回路３４及び電源３１〜３３は導電板３０の各部分
Ａ，Ｂ，Ｃ・・・Ｊにそれぞれ除電バイアスを印加する
除電バイアス印加手段を構成する。The conductive plate 30 is arranged in parallel with the transfer paper width direction (direction perpendicular to the transfer paper transfer direction), facing the transfer paper transfer path. The conductive plate 30 is divided into a plurality of parts A, each having a predetermined length (for example, a fixed length) in the transfer paper width direction.
B, C, ... J, and these portions A to J are independently separated by the switching circuit 34 from at least two or more different static elimination bias voltages, for example, three different voltages V 1 and V. 2 , V 3 is power source 3
1 to 33 are selectively applied. Therefore, the switching circuit 34 and the power supplies 31 to 33 constitute a static elimination bias applying means for applying a static elimination bias to the respective portions A, B, C, ... J of the conductive plate 30.

【００３６】図３に示すように画像記憶演算装置３５は
画像処理装置１３からの画像信号を一旦メモリに記憶す
る。また、画像記憶演算装置３５は、記録すべき画像信
号（記録すべき画素の信号）を検出する画像信号検出手
段を兼ね、図４に示すように転写紙３６を除電用電極３
０の各部分Ａ〜Ｊに対応して転写紙幅方向へ複数に分割
すると共に転写紙搬送方向に複数に所定の長さ（例えば
一定の長さ）毎に分割することにより、複数の領域０Ａ
〜０Ｊ，１Ａ〜１Ｊ，２Ａ〜２Ｊ・・・ｎＡ〜ｎＪに分
割し、上記メモリに記憶した画像信号から転写紙３６の
各領域０Ａ〜ｎＪに転写される画像の面積率（画像部の
全体に対する面積率）ｓを求める。As shown in FIG. 3, the image storage / calculation device 35 temporarily stores the image signal from the image processing device 13 in the memory. The image storage / calculation device 35 also serves as an image signal detecting means for detecting an image signal to be recorded (a signal of a pixel to be recorded), and as shown in FIG.
A plurality of areas 0A are obtained by dividing the transfer paper in the transfer paper width direction into a plurality of areas A to J corresponding to 0 and dividing the transfer paper in the transfer paper conveyance direction into a plurality of predetermined lengths (for example, constant lengths).
.About.0J, 1A to 1J, 2A to 2J ... nA to nJ, and the area ratio of the image transferred to each area 0A to nJ of the transfer paper 36 from the image signal stored in the memory (the entire image area). Area ratio) s is calculated.

【００３７】そして、画像記憶演算装置３５は、転写紙
３６の各領域毎の画像面積率ｓから除電用電極３０の各
部分Ａ〜Ｊに印加する除電バイアス電圧を決定し、例え
ば０≦ｓ＜３０％の時は除電バイアス電圧をＶ4に決定
し、３０％≦ｓ＜６５％の時は除電バイアス電圧をＶ5
に決定し、６５％≦ｓ≦１００％の時は除電バイアス電
圧をＶ6に決定し、これらの決定した除電バイアス電圧
を転写紙３６の各領域が除電位置を通過する時にスウィ
ッチング回路３４に指示する信号を出力する。Then, the image storage / calculation device 35 determines the static elimination bias voltage to be applied to the respective portions A to J of the static elimination electrode 30 from the image area ratio s of each region of the transfer paper 36, for example 0 ≦ s < When 30%, the static elimination bias voltage is determined to be V 4 , and when 30% ≦ s <65%, the static elimination bias voltage is V 5
When 65% ≦ s ≦ 100%, the static elimination bias voltage is determined to be V 6, and the determined static elimination bias voltage is applied to the switching circuit 34 when each region of the transfer paper 36 passes the static elimination position. Output the signal to instruct.

【００３８】スウィッチング回路３４は除電用電極３０
の各部分Ａ〜Ｊに対してそれぞれ電源３１〜３３からの
３種類の除電バイアス電圧Ｖ4，Ｖ5，Ｖ6を画像記憶演
算装置３５の指示に従って印加する。すなわち、スウィ
ッチング回路３４は、転写紙３６の幅方向へ一列に配列
された領域０Ａ〜０Ｊが除電用電極３０と感光体ドラム
１１との間の除電位置を通過する時ｔ0には除電用電極
３０の各部分Ａ〜Ｊに対してそれぞれ電源３１〜３３か
らの３種類の除電バイアス電圧Ｖ4，Ｖ5，Ｖ6を転写紙
３６の各領域０Ａ〜０Ｊの画像面積率に応じて印加し、
転写紙３６の幅方向へ一列に配列された領域１Ａ〜１Ｊ
が除電用電極２０と感光体ドラム１１との間の除電位置
を通過する時ｔ1には除電用電極３０の各部分Ａ〜Ｊに
対してそれぞれ電源３１〜３３からの３種類の除電バイ
アス電圧Ｖ4，Ｖ5，Ｖ6を転写紙２６の各領域１Ａ〜１
Ｊの画像面積率に応じて印加し、転写紙２６の幅方向へ
一列に配列された部分２Ａ〜２Ｊが除電用電極３０と感
光体ドラム１１との間の除電位置を通過する時ｔ2には
除電用電極２０の各部分Ａ〜Ｊに対してそれぞれ電源３
１〜３３からの３種類の除電バイアス電圧Ｖ4，Ｖ5，Ｖ
6を転写紙２６の各領域２Ａ〜２Ｊの画像面積率に応じ
て印加するというように除電用電極３０の各部分Ａ〜Ｊ
に対してそれぞれ電源３１〜３３からの３種類の除電バ
イアス電圧Ｖ 4，Ｖ5，Ｖ6を画像記憶演算装置３５の指
示に従って印加する。The switching circuit 34 is used for the static elimination electrode 30.
From the power sources 31 to 33 for the respective parts A to J of
Three types of static elimination bias voltage VFour, VFive, V6Image memory performance
The voltage is applied according to the instruction of the computing device 35. I.e.
The hatching circuits 34 are arranged in a line in the width direction of the transfer paper 36.
The areas 0A to 0J that are formed are the charge eliminating electrode 30 and the photosensitive drum.
When passing through the static elimination position between 11 and t0For static elimination electrode
Power sources 31 to 33 for the respective parts A to J of 30
3 types of static elimination bias voltage VFour, VFive, V6Transfer paper
36 areas 0A to 0J are applied according to the image area ratio,
Areas 1A to 1J arranged in a line in the width direction of the transfer paper 36
Is a static elimination position between the static elimination electrode 20 and the photosensitive drum 11.
When passing through t1For each part A to J of the static elimination electrode 30
On the other hand, three types of charge removal bypasses from the power supplies 31 to 33, respectively.
As voltage VFour, VFive, V6Each area 1A to 1 of the transfer paper 26
It is applied according to the image area ratio of J, and is applied in the width direction of the transfer paper 26.
The portions 2A to 2J arranged in a line are considered to be the electrodes 30 for static elimination.
When passing through the static elimination position between the photoconductor drum 11 and t2In
A power source 3 is provided for each of the portions A to J of the static elimination electrode 20.
Three types of static elimination bias voltage V from 1 to 33Four, VFive, V
6According to the image area ratio of each area 2A to 2J of the transfer paper 26.
Each portion A to J of the static elimination electrode 30 is applied by applying
Against each of the three types of static elimination
Iias voltage V Four, VFive, V6The finger of the image storage / calculation device 35.
Apply as indicated.

【００３９】例えば、スウィッチング回路３４は、転写
紙３６の幅方向へ一列に配列された領域１Ａ〜１Ｊが除
電用電極３０と感光体ドラム１１との間の除電位置を通
過する時ｔ1には、転写紙２６の領域１Ｂの画像面積率
ｓ1Bがｓ1B＝２０％であれば電源３１からの除電バイア
ス電圧Ｖ4を除電用電極３０の分割部分Ｂに印加し、転
写紙２６の領域１Ｃの画像面積率ｓ1Cがｓ1C＝３２％で
あれば電源３２からの除電バイアス電圧Ｖ5を除電用電
極３０の分割部分Ｃに印加し、転写紙３６の領域１Ｄの
画像面積率ｓ1Dがｓ1D＝５０％であれば電源３２からの
除電バイアス電圧Ｖ5を除電用電極３０の分割部分Ｄに
印加し、転写紙２６の領域１Ｅの画像面積率ｓ1Eがｓ1E
＝７０％であれば電源３３からの除電バイアス電圧Ｖ6
を除電用電極３０の分割部分Ｅに印加する。[0039] For example, switchgrass ring circuit 34, the t 1 when the area 1A~1J arranged in a row in the width direction of the transfer sheet 36 passes through a neutralization position between the neutralizing electrode 30 and the photosensitive drum 11 When the image area ratio s 1B of the area 1B of the transfer paper 26 is s 1B = 20%, the static elimination bias voltage V 4 from the power source 31 is applied to the divided portion B of the static elimination electrode 30, and the area of the transfer paper 26 is When the image area ratio s 1C of 1C is s 1C = 32%, the discharging bias voltage V 5 from the power source 32 is applied to the divided portion C of the discharging electrode 30, and the image area ratio s 1D of the region 1D of the transfer paper 36 is applied. Is s 1D = 50%, the static elimination bias voltage V 5 from the power source 32 is applied to the divided portion D of the static elimination electrode 30, and the image area ratio s 1E of the region 1E of the transfer paper 26 is s 1E.
= 70%, the static elimination bias voltage V 6 from the power source 33
Is applied to the divided portion E of the static elimination electrode 30.

【００４０】この第２の例では、除電用電極３０の各部
分Ａ〜Ｊに対して複数種類の除電バイアス電圧を転写紙
幅方向位置に応じて同時に印加するので、除電用電極３
０の各部分Ａ〜Ｊに対して最適な除電バイアス電圧を印
加することができ、余分な電力消費を防ぐことができ
る。また、転写材除電装置はコロナ除電装置であるの
で、余分なオゾン発生を防ぐことができる。In the second example, since a plurality of types of charge-eliminating bias voltages are simultaneously applied to the respective portions A to J of the charge-eliminating electrode 30, the charge-eliminating electrode 3 is applied.
It is possible to apply an optimum static elimination bias voltage to each of the portions A to J of 0, and it is possible to prevent excessive power consumption. Further, since the transfer material charge eliminator is a corona charge eliminator, it is possible to prevent excessive ozone generation.

【００４１】また、画像記憶演算装置３５は、記録すべ
き画像信号を検出する画像信号検出手段を兼ね、除電用
電極３０の各部分Ａ〜Ｊに印加する除電バイアスの電圧
値と印加位置を記録すべき画像信号に応じて決定するの
で、画像信号に応じて最適な除電バイアスを除電用電極
３０の各部分Ａ〜Ｊに印加することができ、過剰な電圧
印加による感光体ドラム１１の疲労や抵抗低下を防ぐこ
とができる。また、転写材には画像情報の多い部分に不
要な電荷を与えずに余分な除電バイアス電圧の印加によ
る異常画像を防ぐことができる。さらに、転写材除電装
置２８はのこ歯状（若しくは針状）に形成された導電板
からなる転写用電極３０を用いて構成したので、より簡
単な構成で安価にできる。The image storage / calculation device 35 also functions as an image signal detecting means for detecting an image signal to be recorded, and records the voltage value and the application position of the static elimination bias applied to the respective portions A to J of the static elimination electrode 30. Since it is determined according to the image signal to be processed, it is possible to apply an optimum charge-eliminating bias to each of the portions A to J of the charge-eliminating electrode 30 according to the image signal. Resistance drop can be prevented. Further, it is possible to prevent an abnormal image due to the application of an extra static elimination bias voltage without giving unnecessary charges to a portion having a lot of image information on the transfer material. Furthermore, since the transfer material charge eliminator 28 is configured by using the transfer electrode 30 formed of a conductive plate formed in a sawtooth shape (or a needle shape), the transfer material charge removal apparatus 28 has a simpler structure and can be manufactured at a low cost.

【００４２】[0042]

【発明の効果】以上のように請求項１記載の発明によれ
ば、像担持体の表面にトナー像を形成し、このトナー像
を転写材に転写する画像形成装置における転写装置にお
いて、転写バイアスが印加されて前記像担持体表面のト
ナー像を転写材に転写する転写手段と、この転写手段に
対して少なくとも２つ以上の異なる転写バイアスを転写
材幅方向位置に応じて同時に印加する転写バイアス印加
手段とを備えたので、転写手段に対して最適な転写バイ
アス電圧を印加することができ、余分な電力消費を防ぐ
ことができる。また、コロナ転写装置である場合には、
余分なオゾン発生を防ぐことができる。As described above, according to the first aspect of the invention, in the transfer device in the image forming apparatus for forming the toner image on the surface of the image carrier and transferring the toner image onto the transfer material, the transfer bias is applied. Is applied to transfer the toner image on the surface of the image carrier to a transfer material, and a transfer bias that simultaneously applies at least two different transfer biases to the transfer means according to the position in the width direction of the transfer material. With the provision of the application unit, it is possible to apply an optimum transfer bias voltage to the transfer unit, and it is possible to prevent excessive power consumption. If it is a corona transfer device,
It is possible to prevent excess ozone generation.

【００４３】請求項２記載の発明によれば、請求項１記
載の転写装置において、記録すべき画像信号を検出する
画像信号検出手段の検出結果により、画像信号に応じて
転写バイアスの電圧値と印加位置を決定する手段を備え
たので、画像信号に応じて最適な転写バイアスを転写手
段に印加することができ、過剰な電圧印加による像担持
体の疲労や抵抗低下を防ぐことができる。また、転写材
には画像部以外に不要な電荷を与えずに転写材の分離性
を高めることができる。According to the second aspect of the present invention, in the transfer device according to the first aspect, the voltage value of the transfer bias is determined according to the image signal by the detection result of the image signal detecting means for detecting the image signal to be recorded. Since the means for determining the application position is provided, it is possible to apply an optimum transfer bias to the transfer means according to the image signal, and it is possible to prevent fatigue and resistance reduction of the image carrier due to excessive voltage application. In addition, the separability of the transfer material can be improved without giving unnecessary charges to the transfer material other than the image portion.

【００４４】請求項３記載の発明によれば、像担持体の
表面にトナー像を形成し、このトナー像を転写材に転写
する画像形成装置における転写装置において、のこ歯状
若しくは針状に形成されて転写材幅方向に複数に分割さ
れ、前記像担持体表面のトナー像を転写材に転写する導
電板からなる転写用電極と、この転写用電極の各分割部
分にそれぞれ別々に転写バイアスを印加する転写バイア
ス印加手段とを備えたので、請求項１記載の発明と同様
な効果が得られ、かつ、より簡単な構成で安価にでき
る。According to the invention of claim 3, in a transfer device in an image forming apparatus for forming a toner image on the surface of an image carrier and transferring the toner image onto a transfer material, a saw-toothed or needle-shaped image is formed. The transfer electrode is formed and divided into a plurality of pieces in the width direction of the transfer material, and is composed of a conductive plate for transferring the toner image on the surface of the image carrier to the transfer material, and the transfer bias is separately applied to each divided portion of the transfer electrode. Since the transfer bias applying means for applying is provided, the same effect as that of the invention according to claim 1 can be obtained, and the cost can be reduced with a simpler configuration.

【００４５】請求項４記載の発明によれば、像担持体の
表面にトナー像を形成してこのトナー像を転写材に転写
し、この転写材をトナー像転写後に除電する画像形成装
置の転写材除電装置において、除電バイアスが印加され
て転写材を除電する除電手段と、この除電手段に対して
少なくとも２つ以上の異なる除電バイアスを転写材幅方
向位置に応じて同時に印加する除電バイアス印加手段と
を備えたので、除電手段に対して最適な除電バイアス電
圧を印加することができ、余分な電力消費を防ぐことが
できる。また、コロナ除電装置である場合には、余分な
オゾン発生を防ぐことができる。According to the invention described in claim 4, a transfer of an image forming apparatus for forming a toner image on the surface of an image carrier, transferring the toner image to a transfer material, and removing the charge after transferring the transfer material to the transfer material. In a material static eliminator, a static eliminator for applying a static eliminator bias to neutralize a transfer material, and a static eliminator bias applying means for simultaneously applying at least two or more different static eliminator biases to the static eliminator in accordance with a transfer material width direction position Since it is equipped with, it is possible to apply an optimum static elimination bias voltage to the static elimination means, and it is possible to prevent excessive power consumption. Further, in the case of the corona charge eliminating device, it is possible to prevent the generation of extra ozone.

【００４６】請求項５記載の発明によれば、請求項４記
載の転写装置において、記録すべき画像信号を検出する
画像信号検出手段の検出結果により、画像信号に応じて
除電バイアスの電圧値と印加位置を決定する手段を備え
たので、画像信号に応じて最適な除電バイアスを除電手
段に印加することができ、過剰な電圧印加による像担持
体の疲労や抵抗低下を防ぐことができる。また、転写材
には画像情報の多い部分に不要な電荷を与えずに余分な
除電バイアス電圧の印加による異常画像を防ぐことがで
きる。According to the fifth aspect of the present invention, in the transfer device according to the fourth aspect, the voltage value of the static elimination bias is determined according to the image signal according to the detection result of the image signal detecting means for detecting the image signal to be recorded. Since the means for determining the application position is provided, it is possible to apply the optimum charge eliminating bias to the charge eliminating means in accordance with the image signal, and it is possible to prevent fatigue and resistance reduction of the image carrier due to excessive voltage application. Further, it is possible to prevent an abnormal image due to the application of an extra static elimination bias voltage without giving unnecessary charges to a portion having a lot of image information on the transfer material.

【００４７】請求項６記載の発明によれば、像担持体の
表面にトナー像を形成してこのトナー像を転写材に転写
し、この転写材をトナー像転写後に除電する画像形成装
置における転写材除電装置において、のこ歯状若しくは
針状に形成されて転写材幅方向に複数に分割され、転写
材を除電する導電板からなる除電用電極と、この除電用
電極の各分割部分にそれぞれ別々に除電バイアスを印加
する除電バイアス印加手段とを備えたので、請求項４記
載の発明と同様な効果が得られ、かつ、より簡単な構成
で安価にできる。According to the sixth aspect of the present invention, a transfer is performed in an image forming apparatus in which a toner image is formed on the surface of an image carrier, the toner image is transferred to a transfer material, and the transfer material is discharged after the toner image is transferred. In the material static eliminator, a static elimination electrode formed of a sawtooth or needle shape and divided into a plurality of pieces in the width direction of the transfer material, and a static elimination electrode made of a conductive plate for static elimination of the transfer material, and each of the divided portions of the static elimination electrode, respectively. Since the static elimination bias applying means for separately applying the static elimination bias is provided, the same effect as that of the invention of claim 4 is obtained, and the cost can be reduced with a simpler configuration.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明を適用した画像形成装置の第１の例を示
すブロック図である。FIG. 1 is a block diagram showing a first example of an image forming apparatus to which the present invention has been applied.

【図２】同第１の例の一部を説明するための説明図であ
る。FIG. 2 is an explanatory diagram for explaining a part of the first example.

【図３】本発明を適用した画像形成装置の第２の例を示
すブロック図である。FIG. 3 is a block diagram showing a second example of an image forming apparatus to which the present invention has been applied.

【図４】同第２の例の一部を説明するための説明図であ
る。FIG. 4 is an explanatory diagram for explaining a part of the second example.

【符号の説明】[Explanation of symbols]

１１ 感光体ドラム １７ 転写装置 ２０ 転写用電極 ２１〜２３，３１〜３３ 電源 ２４，３４ スウィッチング回路 ２５，３５ 画素記憶演算装置 ２８ 転写材除電装置 ３０ 除電用電極 11 Photosensitive drum 17 Transfer device 20 Transfer electrode 21-23, 31-33 Power supply 24,34 switching circuit 25,35 pixel memory arithmetic unit 28 Transfer material static eliminator 30 Electrode for static elimination

Claims (3)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】像担持体の表面にトナー像を形成してこの
トナー像を転写材に転写し、この転写材をトナー像転写
後に除電する画像形成装置の転写材除電装置において、
除電バイアスが印加されて転写材を除電する除電手段
と、この除電手段に対して少なくとも２つ以上の異なる
除電バイアスを転写材幅方向位置に応じて同時に印加す
る除電バイアス印加手段とを備えたことを特徴とする転
写材除電装置。 1. A toner image is formed on the surface of an image carrier.
Transfer the toner image to the transfer material and transfer the transfer material to the toner image.
In the transfer material charge eliminator of the image forming apparatus that is subsequently neutralized,
Static elimination means for eliminating static charges on a transfer material by applying static elimination bias
And at least two or more different for this static elimination means
A static elimination bias is applied simultaneously according to the position in the width direction of the transfer material.
And a charge removal bias applying means.
Photographic material static eliminator. 【請求項２】請求項１記載の転写装置において、記録す
べき画像信号を検出する画像信号検出手段の検出結果に
より、画像信号に応じて除電バイアスの電圧値と印加位
置を決定する手段を備えたことを特徴とする転写材除電
装置。 2. The transfer device according to claim 1, wherein
The detection result of the image signal detection means that detects the desired image signal
The voltage value of the static elimination bias and the applied voltage
Transfer material static elimination characterized by having means for determining the position
apparatus. 【請求項３】像担持体の表面にトナー像を形成してこの
トナー像を転写材に転写し、この転写材をトナー像転写
後に除電する画像形成装置における転写材除電装置にお
いて、のこ歯状若しくは針状に形成されて転写材幅方向
に複数に分割され、転写材を除電する導電板からなる除
電用電極と、この除電用電極の各分割部分にそれぞれ別
々に除電バイアスを印加する除電バイアス印加手段とを
備えたことを特徴とする転写材除電装置。 3. A toner image is formed on the surface of an image carrier.
Transfer the toner image to the transfer material and transfer the transfer material to the toner image.
In the transfer material charge eliminator of the image forming device that is subsequently neutralized
The transfer material width direction
Is divided into a plurality of parts and is composed of a conductive plate that eliminates static electricity from the transfer material.
Separate the charging electrode and each part of this static elimination electrode.
And a static elimination bias applying means for individually applying the static elimination bias.
A transfer material static eliminator characterized by being provided.
JP15760094A 1994-07-08 1994-07-08 Transfer device and transfer material neutralization device Expired - Fee Related JP3373658B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15760094A JP3373658B2 (en) 1994-07-08 1994-07-08 Transfer device and transfer material neutralization device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15760094A JP3373658B2 (en) 1994-07-08 1994-07-08 Transfer device and transfer material neutralization device

Publications (2)

Publication Number Publication Date
JPH0822204A JPH0822204A (en) 1996-01-23
JP3373658B2 true JP3373658B2 (en) 2003-02-04

Family

ID=15653267

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15760094A Expired - Fee Related JP3373658B2 (en) 1994-07-08 1994-07-08 Transfer device and transfer material neutralization device

Country Status (1)

Country Link
JP (1) JP3373658B2 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3403105B2 (en) * 1998-12-15 2003-05-06 キヤノン株式会社 Image forming device
DE102004013771A1 (en) * 2004-03-20 2005-10-06 Eastman Kodak Co. Method and unloading device for unloading of printing material

Also Published As

Publication number Publication date
JPH0822204A (en) 1996-01-23

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