JPH02264278A - Image forming device - Google Patents
Image forming deviceInfo
- Publication number
- JPH02264278A JPH02264278A JP1085189A JP8518989A JPH02264278A JP H02264278 A JPH02264278 A JP H02264278A JP 1085189 A JP1085189 A JP 1085189A JP 8518989 A JP8518989 A JP 8518989A JP H02264278 A JPH02264278 A JP H02264278A
- Authority
- JP
- Japan
- Prior art keywords
- transfer
- voltage
- image
- paper
- transfer means
- 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.)
- Granted
Links
- 238000012546 transfer Methods 0.000 claims abstract description 195
- 239000000463 material Substances 0.000 claims abstract description 28
- 108091008695 photoreceptors Proteins 0.000 description 41
- 238000000034 method Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 6
- 238000011161 development Methods 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- 230000006866 deterioration Effects 0.000 description 3
- 238000013518 transcription Methods 0.000 description 2
- 230000035897 transcription Effects 0.000 description 2
- 229920002943 EPDM rubber Polymers 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は静電複写機、同プリンタなど、静電転写プロ
セスを利用する画像形成装置、とくに像担持体に対向す
る転写手段を利用する画像形成装置に関するものである
。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to image forming apparatuses that utilize an electrostatic transfer process, such as electrostatic copying machines and printers, and particularly to image forming apparatuses that utilize a transfer means facing an image carrier. The present invention relates to a forming device.
［背景技術］
従来、像担持体と、これに圧接する転写部材とをそなえ
、これら両者の間を転写材を通過させるとともに、この
とき転写部材にバイアス電圧を印加して、像担持体側の
トナー像を転写材に転写するように構成した画像形成装
置がすでに提案されている。[Background Art] Conventionally, an image carrier and a transfer member pressed against the image carrier are provided, and a transfer material is passed between the two, and at this time, a bias voltage is applied to the transfer member to transfer toner on the image carrier side. Image forming apparatuses configured to transfer an image to a transfer material have already been proposed.
第９図はこのような画像形成装置の典型的な例を示す概
略側面図である。FIG. 9 is a schematic side view showing a typical example of such an image forming apparatus.
紙面に垂直方向に軸線を有し、図示矢印Ｘ方向に回転す
る円筒状の像担持体たる感光体ｌの表面が、電源４によ
って、帯電ローラ３を介して一様に帯電されたのち、画
像情報書込み手段７によって１画像変調されたレーザビ
ーム、スリット露光などによって該帯電面に画像情報か
付与されて静電ＷＩ像が形成される。After the surface of a photoreceptor l, which is a cylindrical image carrier having an axis perpendicular to the plane of the paper and rotating in the direction of the arrow X shown in the figure, is uniformly charged by a power source 4 via a charging roller 3, an image is formed. Image information is applied to the charged surface by a single image modulated laser beam, slit exposure, etc. by the information writing means 7, and an electrostatic WI image is formed.
ついでこの潜像に現像器９によってトナーか供給されて
トナー像が形成される。Next, toner is supplied to this latent image by a developing device 9 to form a toner image.
感光体ｌの回転にともなってこのトナー像か、転写部材
たる転写ローラ２が感光体１に当接するニップ部たる転
写部位に到達すると、該トナー像とタイミングを合せて
転写材Ｐもこの転写部位に到来し、このとき該転写ロー
ラ２に転写バイアスを印加して転写材裏面にトナーと反
対極性の電荷を付与し、感光体ｌのトナー像を転写材に
転移させるものとする。As the photoconductor l rotates, when this toner image reaches a transfer site, which is a nip, where the transfer roller 2, which is a transfer member, comes into contact with the photoconductor 1, the transfer material P also moves to this transfer site in synchronization with the toner image. At this time, a transfer bias is applied to the transfer roller 2 to apply a charge of opposite polarity to the toner to the back surface of the transfer material, thereby transferring the toner image on the photoreceptor 1 to the transfer material.
図示の装置においては、感光体として
ＯＰＣ感光体を使用してプロセススピードを２３１膳／
ｓｅｃとし、帯電手段としては感光体ｌに圧接従動して
これを負帯電させるために交流電圧と直流電圧の重畳電
圧を印加した帯電ローラ３を、転写手段としてはこれも
感光体ｌに圧接従動し、転写材裏面に正電荷を付与する
低体積抵抗の転写ローラ２を用いた。In the illustrated apparatus, an OPC photoreceptor is used as the photoreceptor, and the process speed is 231/
sec, the charging means is a charging roller 3 applied with a superimposed voltage of alternating current and direct current voltage in order to negatively charge the photoreceptor l by pressure contact, and the transfer means is a charging roller 3 which is also driven in pressure contact with the photoreceptor l. A transfer roller 2 having a low volume resistance and applying a positive charge to the back surface of the transfer material was used.
感光体への画像露光は現像してトナーか付着すべき部分
に対して行なわれ、現像器９によって感光体の帯電極性
と同極性のトナーによって反転現像を行なった。Image exposure to the photoreceptor was carried out on a portion to which toner should be adhered after development, and reversal development was carried out using a developing device 9 with toner having the same polarity as the charged polarity of the photoreceptor.
第１０図は上記装置のシーケンスを示すものである。FIG. 10 shows the sequence of the above device.
［発明が解決しようとしている問題点］このような接触
転写方式をとる画像形成装置は、従来からひろく実用さ
れているコロナ放電器を使用するものに比して、高圧電
源を必要としないのでコスト的に有利である。コロナワ
イヤ電極もないのでそれの汚れによる障害もない、高圧
放電に基づくオゾンの発生や、窒化物の生成もなく、こ
れらによる感光体、画質の劣化なども少ないなど種々な
利点がある。しかし、その反面、転写ローラ２が環境に
よって、これに印加する電圧と、これを流れる電流との
関係（Ｖ−１特性という）が大きく変化することが知ら
れている。[Problem to be solved by the invention] Image forming apparatuses that use this type of contact transfer method do not require a high-voltage power source, so they are less expensive than those that use a corona discharger, which has been widely used in the past. It is advantageous. Since there is no corona wire electrode, there are no problems due to contamination of the electrode, there is no generation of ozone or nitrides due to high-pressure discharge, and there is little deterioration of the photoreceptor or image quality due to these. However, on the other hand, it is known that the relationship between the voltage applied to the transfer roller 2 and the current flowing through it (referred to as V-1 characteristic) changes greatly depending on the environment of the transfer roller 2.
即ち、低温低湿環境下（ｔＳｏＣ、１０％、以下Ｌ／Ｌ
という）では、転写ローラの抵抗値は常温常湿（２３°
Ｃ，６４％、以ドＮ／Ｎという）時のそれより色数桁上
界する。反対に、高温高湿（３２，５°Ｃ８５駕以下Ｈ
／Ｈという）環境下では、抵抗かＮ／Ｎに比して１〜２
桁下がる。That is, under a low temperature and low humidity environment (tSoC, 10%, hereinafter L/L)
), the resistance value of the transfer roller is at room temperature and humidity (23°
C, 64%, which is several orders of magnitude higher than that for C, 64% (hereinafter referred to as DoN/N). On the contrary, high temperature and high humidity (32.5°C 85 degrees or less H)
/H) environment, the resistance is 1 to 2 compared to N/N.
Decrease in digits.
このような環境の差異によるＶ−１特性の変動を第１１
図に示しである。The 11th change in V-1 characteristics due to such environmental differences is
It is shown in the figure.
同図における実線は、Ｌ／Ｌ、Ｎ／Ｎ、Ｈ／Ｈ各状態に
おける、最初に画像形成を行うとき転写を行う前の感光
体の前回転蒔、画像形成を終了して転写を行った後の感
光体の後回転時、連続して画像形成を行うときの転写時
と転写時の間の紙間などの非通紙時で、帯電ローラ３の
印加電圧が交直流周成分ともオンとなっているとき（交
流電圧のピーク間電圧１４００Ｖｐｐ、直流電圧７０口
Ｖ）の転写ローラ２におけるＶ−Ｉ特性を、また、破線
は、前記と同様の状態における。Ａ４サイズの転写材か
前述の転写部位を通過する通紙時の転写ローラ２におけ
るＶ−Ｉ特性をそれぞれ示している。The solid lines in the figure indicate the pre-rotation of the photoreceptor before transfer when image formation is performed for the first time in the L/L, N/N, and H/H states, and the transfer after image formation is completed. During the subsequent rotation of the photoreceptor, when paper is not passing, such as during the paper interval between transfers during continuous image formation, the voltage applied to the charging roller 3 is turned on for both AC and DC circumferential components. The broken line indicates the V-I characteristic of the transfer roller 2 when the transfer roller 2 is in the same condition as described above (AC voltage peak-to-peak voltage 1400 Vpp, DC voltage 70 V). The VI characteristics of the transfer roller 2 when an A4 size transfer material passes through the above-mentioned transfer site are shown.
このような公知装置の場合、実験によると、良好な転写
が行われるには、通紙時の転写電流が０．５〜４ｐＡ必
要であること、これか５ルＡをこえると、帯電極性か負
極性のＯＰＣ感光体の特に非道紙部に対応する領域で正
電位の転写メモリーか残り、次に画像を形成するとき画
像に地力ブリが発生することが判明している。In the case of such a known device, experiments have shown that in order to perform good transfer, a transfer current of 0.5 to 4 pA is required when paper is passed, and that if it exceeds 5 μA, the charging polarity may deteriorate. It has been found that positive potential transfer memory remains on the negative polarity OPC photoreceptor, particularly in the area corresponding to the non-printing paper area, and this causes ground blur in the image when the next image is formed.
この転写メモリーとは、像担持体としての感光体か転写
のときに過剰に帯電されると、その電荷を前露光等の除
電手段によっても除電しきれず次に画像形成を行うとき
過剰に帯電されていた部分の電位が高くなり、そこで画
像かカブリなどの濃度ムラとなってしまう現象である。This transfer memory is a type of transfer memory that, when a photoreceptor as an image bearing member is excessively charged during transfer, the charge cannot be completely removed even by pre-exposure or other charge-eliminating means, and the next time image formation is performed, the excess charge is generated. This is a phenomenon in which the potential of the previously exposed areas becomes high, causing uneven density in the image, such as fogging.
このことから、公知装置における適正な転写バイアスは
、Ｈ／Ｈ”？’は約３００〜５００ｖ、Ｎ／Ｎでは約４
００〜７５０ｖ、さらにＬ／Ｌでは約１２５０〜２００
０Ｖであることが判る。From this, the appropriate transfer bias in known devices is approximately 300 to 500 V for H/H"?' and approximately 4 V for N/N.
00~750v, and about 1250~200 for L/L
It can be seen that the voltage is 0V.
このような装置によって定電圧制御を行うと、以下のよ
うな問題が生ずる。When constant voltage control is performed using such a device, the following problems occur.
即ち、Ｎ／Ｎ環境下において適切な転写か行われるよう
に、たとえば転写ローラを
５００ｖで定電圧制御すると、Ｈ／Ｈにおいてはほぼ同
様の転写特性を示すか、Ｌ／Ｌにおいては転写電流がゼ
ロとなり転写不良を招来する。In other words, if the transfer roller is controlled at a constant voltage of 500V, for example, in order to perform appropriate transfer under N/N environment, the transfer characteristics will be almost the same in H/H, or the transfer current will be lower in L/L. It becomes zero, leading to poor transfer.
また、Ｌ／Ｌ環境下における転写性を向上させるように
電圧を設定すると、Ｎ／Ｎ、Ｈ／Ｈ環境において非通紙
部に対応する。ｐｃ感光体に正の転写メモリーが発生し
て、出力画像に地力ブリを生ずる。とくにＨ／Ｈ時にお
いては、通紙時にも転写電流が増大するために電荷が転
写材を貫通して、感光体表面の負のトナーを逆極性に帯
電させて転写不良を起こす。Further, if the voltage is set to improve the transferability in the L/L environment, it corresponds to the non-sheet passing portion in the N/N and H/H environments. Positive transfer memory occurs on the PC photoreceptor, causing ground blur in the output image. Particularly during H/H, since the transfer current increases even when paper is passed, the charge penetrates the transfer material, charging the negative toner on the surface of the photoreceptor to the opposite polarity, causing a transfer failure.
このような事態に対処すべく、定電流制御を行うと、以
下のような問題が生ずる。If constant current control is performed to cope with such a situation, the following problems will occur.
一般に、この種の装置においては、使用可使の最大サイ
ズ転写材以下の範囲で小サイズの転写材をも使用できる
ようになっているのが普通であり、このため、小サイズ
の転写材を使用したときには１通紙時でも感光体長手方
向で感光体と転写ローラとか直接当接する紙の存在しな
い非通紙部分があることになる。そして前述の公知装置
の場合、Ｉ＃ＬＡて定電流制御したとすると、上記の直
接当接する非通紙部に流入する単位面積当たり電流値が
前回転時、後回転時、紙間などの非通紙時に１ｐＡ流し
た場合の単位面積当たり電流値とほぼ等しくなるので、
転写ローラにかかる電圧が降下し、上記非通紙部に比べ
て通紙領域にはほとんど電流が流れなくなって転写不良
を発生する。Generally, in this type of device, it is possible to use small-sized transfer materials within the range of the maximum usable size transfer material, and for this reason, small-sized transfer materials can be used. When used, even when one sheet is passed, there is a non-sheet passing portion in the longitudinal direction of the photoconductor where there is no paper in direct contact with the photoconductor and the transfer roller. In the case of the above-mentioned known device, if constant current control is performed using I#LA, the value of the current per unit area flowing into the above-mentioned directly contacting non-sheet passing portion will be different during the front rotation, during the rear rotation, and due to the difference between sheets, etc. This is approximately equal to the current value per unit area when 1 pA is applied during paper passing, so
The voltage applied to the transfer roller drops, and almost no current flows through the paper passing area compared to the paper non-passing area, resulting in a transfer failure.
上記の場合、Ａ４サイズの通紙時に比して。In the above case, compared to when passing A4 size paper.
封筒を通紙した場合には、Ｈ／Ｈでは
２００ｖ強、Ｎ／Ｎでは２００ｖ弱、Ｌ／Ｌでは約４０
０ｖ程度、転写電圧が降下し、転写材に流れる電流はほ
ぼゼロとなって転写不良を発生する。When passing through an envelope, the voltage is over 200v for H/H, a little less than 200v for N/N, and about 40v for L/L.
The transfer voltage drops to about 0 V, and the current flowing through the transfer material becomes almost zero, causing a transfer failure.
小サイズ通紙時にも充分な転写性を得ようとすると、た
とえばレターサイズ紙とＡ４サイズ紙との差のような比
較的狭い非通紙部分では、これに流入する電流密度が大
きくなって、感光体表面に転写メモリーによる地力ブリ
か発生して、次のレターサイズ紙に裏汚れか生ずる。In order to obtain sufficient transfer performance even when passing small size paper, the current density flowing into relatively narrow non-paper passing areas, such as the difference between letter size paper and A4 size paper, increases. The surface of the photoreceptor is smudged due to the transfer memory, and the back of the next letter-sized paper is smudged.
これは要するに、この種の公知の装置においては、定電
圧制御、定電流制御のいずれの方式によっても、すべて
の環境において、すべてのサイズの転写材に対して良好
な、転写性をもたせることは困難であるのが現状であっ
た。In short, with this type of known device, it is not possible to provide good transfer performance for all sizes of transfer materials in all environments, regardless of whether constant voltage control or constant current control is used. The current situation was difficult.
［発明の目的］
本発明はこのような事態に対処すべくなされたものであ
って、上記のような欠点を解消し、すべてのサイズの転
写材に対して、あらゆる環境下において安定して良好な
転写性が得られるような画像形成装置を提供することを
目的とするものである。[Object of the Invention] The present invention has been made in order to cope with such a situation, and it eliminates the above-mentioned drawbacks and provides stable and good performance for transfer materials of all sizes under all environments. It is an object of the present invention to provide an image forming apparatus that can provide excellent transfer performance.
［発明の構１＆］
像担持体と、像担持体に対向して、像担持体表面に形成
された像を転写部位において転写材へ転写する転写手段
と、を有する画像形成装置において、少なくとも転写部
位か非画像域の時に転写手段を所定の電流（１により定
電流制御し、この時転写手段に生じた電圧をＶ１とする
と、転写部位が画像域の時は、前記電圧値Ｖｌに所定の
係数Ｒ（Ｒ＞１）を乗じたバイアスｖ２で、前記転写手
段を定電圧制御することを特徴とするものである。[Structure 1 & of the Invention] In an image forming apparatus including an image carrier and a transfer means that faces the image carrier and transfers an image formed on the surface of the image carrier to a transfer material at a transfer site, at least the transfer When the transfer area is in a non-image area, the transfer means is controlled with a constant current (1), and the voltage generated in the transfer means at this time is V1. When the transfer area is in an image area, the voltage value Vl is set to a predetermined value. The present invention is characterized in that the transfer means is controlled at a constant voltage by a bias v2 multiplied by a coefficient R (R>1).
［実施例］
第１図は本発明を適用するに適した画像形成装置の構成
を示す概略側面図であって、矢印Ｘ方向に、プロセスス
ピード２３ ａｍ／ ｓｅｃで回転する直径３０ｍｍの
ＯＰＣ感光感光体表面が。[Example] FIG. 1 is a schematic side view showing the configuration of an image forming apparatus suitable for applying the present invention, in which an OPC photosensitive sensor with a diameter of 30 mm rotates in the direction of arrow X at a process speed of 23 am/sec. The body surface.
帯電ローラ３によって一様に負帯電されたのち、該帯電
面に、たとえば画像変調されたレーザど−ムが投射され
てその部分の電位を減衰させて静電潜像が形成される。After being uniformly negatively charged by the charging roller 3, an image-modulated laser beam, for example, is projected onto the charged surface to attenuate the potential of that portion and form an electrostatic latent image.
ここで潜像を形成するための帯電手段としては、帯電ロ
ーラ３に限らずコロナ放電器を使用することも可ｆ＃、
である。Here, as a charging means for forming a latent image, not only the charging roller 3 but also a corona discharger can be used.
It is.
潜像形成後感光体ｌの回転にともなって該潜像が現像器
６に対向する位置に来ると、前記潜像に負帯電したトナ
ーか供給され、反転現像方式によって上記の光照射され
て電位か減衰した部分にトナー像か形成される。After the latent image is formed, when the latent image comes to a position facing the developing device 6 as the photoreceptor l rotates, negatively charged toner is supplied to the latent image, and the above-mentioned light is irradiated by the reversal development method to increase the potential. A toner image is formed in the attenuated area.
感光体ｌの走行方向にみて現像器の下流側において、該
感光体に圧接する転写用回転体としての導電性転写ロー
ラ２か圧接配置してあり、両者の圧接ニップ部が、下記
のように、転写部位（転写位置）を形成している。On the downstream side of the developing device when viewed in the traveling direction of the photoreceptor 1, a conductive transfer roller 2 as a transfer rotating body is placed in pressure contact with the photoreceptor, and the pressure nip between the two is as shown below. , forming a transcription site (transcription position).
トナー像が該転写部位に到来すると、これとタイミング
を合せて搬送路７から転写材Ｐが転写部位に供給され、
これとともに転写ローラ２に電源により印加される正の
転写バイアスによって、感光体表面のトナー像は転写材
に転移する。When the toner image arrives at the transfer site, the transfer material P is supplied to the transfer site from the conveyance path 7 in synchronization with this,
At the same time, the toner image on the surface of the photoreceptor is transferred to the transfer material by a positive transfer bias applied to the transfer roller 2 by the power source.
ここで、転写ローラ２と感光体ｌとの間に転写材Ｐの厚
みより小さい間隙があっても良く、この時はその間隙を
転写材Ｐが通過する時だけ転写材Ｐか感光体ｌと転写ロ
ーラ２との間に圧接される。Here, there may be a gap between the transfer roller 2 and the photoreceptor l that is smaller than the thickness of the transfer material P, and in this case, only when the transfer material P passes through the gap, either the transfer material P or the photoreceptor l It is pressed into contact with the transfer roller 2.
上記転写ローラ２にたいしては、本出願人により先に出
願された特願昭６：ｌ−２７６１０６号に示す定電圧制
御、定電流制御（Ａ Ｔ Ｖ Ｃ、ＡｃｔｉｖｅＴｒａ
ｎｓｆｅｒ Ｖｏｌｔａｇｅ Ｃｏｎｔｒｏｌ）可能な
電源４によって、夫々所定の時点で所定の電圧を印加す
るようになっているものとする。The transfer roller 2 is controlled by constant voltage control, constant current control (ATVC, ActiveTra
It is assumed that a power source 4 capable of controlling voltage (voltage control) is configured to apply a predetermined voltage at a predetermined time point.
コンピュータなどの外部装置からＣＰＵ８がプリント信
号をうけると、ＣＰＵ８は感光体ｌを駆動するモータド
ライブ回路（不図示）にメインモータの駆動オン信号を
送り、同時に電１（４に一次高圧オン信号をおくって帯
電ローラ３に帯電バイアスを印加して感光体１表面を、
たとえば、暗電位Ｖｄ −７００Ｖに帯電させるものと
する。When the CPU 8 receives a print signal from an external device such as a computer, the CPU 8 sends a main motor drive ON signal to the motor drive circuit (not shown) that drives the photoconductor 1, and at the same time sends a primary high voltage ON signal to the electric current 1 (4). A charging bias is applied to the charging roller 3 to charge the surface of the photoreceptor 1.
For example, it is assumed that the dark potential Vd is charged to -700V.
ついでＣＰＵが不図示の画像情報書込み手段を駆動させ
て静電潜像を形成する。Next, the CPU drives an image information writing means (not shown) to form an electrostatic latent image.
つぎに、ＣＰＵ８が電源４に転写オン信号をおくり、こ
れによって、電源４によって後述するような、定電圧、
定電流制御が実行されるものとする。Next, the CPU 8 sends a transfer-on signal to the power source 4, which causes the power source 4 to generate a constant voltage as described below.
It is assumed that constant current control is performed.
電ＩＱ４は、転写オン信号をうけとめると、少なくとも
転写部位て感光体か非画像域のとき、即ち非通紙のとき
転写ローラ２を定電流制御する。図示の装置においては
、２ルＡの転写電流を流すものとする。つぎにＣＰＵ８
は転写ローラ２に生じた電圧Ｖｌを非通紙の間の任意の
時に記七〇シ、ついて、転写部位で感光体が画像域のと
き、即ち通紙時は、さきに記憶した電圧ｖ１に、係数Ｒ
（Ｒ＞１）を掛けた電圧ｖ２で、転写ローラ２に対して
定電圧制御を行い感光体のトナー像を転写紙に転写する
。本実施例ではｖｌを記憶したら、即ｖ２で定電圧制御
する様になっている。またＶｔは記憶するタイミングに
より多少ばらつくが問題はない。また係数Ｒ（Ｒ＞１）
は、感光体ドラムの転写メモリーに対する能力、転写ロ
ーラの抵抗の均−性等を考慮して適正な値を決める。ま
た、Ｖｌは定電流時に何回かサンプリングして、平均値
を用いてもよいし、瞬時にサンプルした値てもかまわな
い。When the electric current IQ4 receives the transfer ON signal, it controls the transfer roller 2 with a constant current at least when the transfer site is on the photoreceptor or in a non-image area, that is, when the paper is not passing. In the illustrated apparatus, it is assumed that a transfer current of 2 A is applied. Next CPU8
records the voltage Vl generated in the transfer roller 2 at any time while the paper is not passing, and when the photoreceptor is in the image area at the transfer site, that is, when paper is passing, the voltage V1 that was previously stored is recorded. , coefficient R
Constant voltage control is applied to the transfer roller 2 using a voltage v2 (R>1), and the toner image on the photoreceptor is transferred onto the transfer paper. In this embodiment, when vl is memorized, constant voltage control is immediately performed using v2. Further, although Vt varies somewhat depending on the timing of storage, there is no problem. Also, the coefficient R (R>1)
An appropriate value is determined by considering the transfer memory capacity of the photosensitive drum, the uniformity of resistance of the transfer roller, etc. Further, Vl may be sampled several times during constant current and an average value may be used, or a value sampled instantaneously may be used.
また、プロセススピードか大きい場合は、良好な転写を
行うのに転写時の転写バイアスを大きくしなければなら
ないので、本発明は、特に有効で前回転、紙間の定電流
制御時に流す電流値を小さく押えることかでき、高圧電
源の負担を軽くすることができる。また、転写メモリー
の発生しやすい感光体や、転写ローラ周方向で抵抗がば
らつく転写ローラに対しても、係数Ｒを大きくとること
によって非転写時（非通紙時）に流す電流をおさえるこ
とで転写メモリーを防止でき、転写ローラの周方向で多
少抵抗がばらついても転写時だけ大きい転写バイアスな
印加できるので材料に対して、使用上のラチチュードを
大きくすることかできる。In addition, when the process speed is high, the transfer bias during transfer must be increased to perform good transfer, so the present invention is particularly effective in controlling the current value flowing during pre-rotation and constant current control between sheets. It can be kept small and the burden on the high-voltage power supply can be reduced. In addition, by setting a large coefficient R, it is possible to suppress the current flowing during non-transferring (when paper is not passing) for photoconductors that are prone to transfer memory and for transfer rollers that have varying resistance in the circumferential direction of the transfer roller. Transfer memory can be prevented, and even if the resistance varies somewhat in the circumferential direction of the transfer roller, a large transfer bias can be applied only during transfer, so the latitude in use can be increased for the material.
本実施例では、係数Ｒを１．５と決めた０本実施例のシ
ーケンスを第２図に示す。In this embodiment, the sequence of the zero embodiment in which the coefficient R is set to 1.5 is shown in FIG.
つぎに、本実施例の種々な環境下における作用を第３図
によって説明する。第３図は、従来例で用いた転写ロー
ラ２のＶＩ特性と同一のものである。Next, the operation of this embodiment under various environments will be explained with reference to FIG. FIG. 3 shows the same VI characteristics of the transfer roller 2 used in the conventional example.
第３図のＶＩ特性は、転写ローラとして直径１６．６膳
ｌ、肉厚５ＩＩ−のＥＰＤＭを用い転写ローラの抵抗は
Ｌ／Ｌのとき１０８〜１０９Ω、Ｎ／間のとき１０’〜
１０’Ω、Ｈ／Ｈのとき１０’〜１０’Ωである。この
ＶＩ特性は、転写ローラの特性により変るのはもちろん
である。The VI characteristics shown in Fig. 3 are as follows: EPDM with a diameter of 16.6 mm and a wall thickness of 5II- is used as the transfer roller, and the resistance of the transfer roller is 108 to 109 Ω when L/L, and 10' to 10' when N/.
10'Ω, and 10' to 10'Ω when H/H. Of course, this VI characteristic changes depending on the characteristics of the transfer roller.
Ｈ／Ｈ環境下において、非通紙時（非転写時）には、電
源４が転写ローラ２に対して２ｐＡの定電流制御を行う
、これによって転写ローラには、２５０ｖの電圧が発生
するので、これをホールドしてｖｌとし、そして１通紙
時には、Ｖｌを１．５倍して、Ｖ２とした電圧（３７５
Ｖ）により定電圧制御を行う。これによって、全てのサ
イズの紙に対して、第３図に示した様に、１ｐＡの転写
電流が得られ、良好な転写性が得られる。In an H/H environment, when paper is not passing (non-transferring), the power supply 4 controls the transfer roller 2 with a constant current of 2pA, which generates a voltage of 250V on the transfer roller. , this is held and set as vl, and when one sheet is passed, Vl is multiplied by 1.5 to set the voltage as V2 (375
V) performs constant voltage control. As a result, a transfer current of 1 pA can be obtained for all sizes of paper, as shown in FIG. 3, and good transferability can be obtained.
また、前回転や紙間の定電流制御時は、５７ｔＡ以下の
２終ＡＬか流していないので、転写ローラ２のローラ周
方向の抵抗のバラツキを考えても、転写プラスメモリー
による地力ブリの発生はなく、さらに、感光体ドラムｌ
の帯電による劣化も少なく、感光体ドラムの長寿命化に
つながる。さらに、大サイズ紙と小サイズ紙との差の非
通紙領域においてもその電流密度は、適止な係数Ｒを選
ぶことによって、５．Ａ相当時を超えることを防ぐこと
ができるので、感光体に転写メモリーか残ることはない
。In addition, during pre-rotation and constant current control between sheets, the second final AL of 57 tA or less is not flowing. In addition, there is no photoreceptor drum l.
There is also less deterioration due to charging, leading to a longer life of the photoreceptor drum. Furthermore, by selecting an appropriate coefficient R, the current density in the non-paper passing region between large-sized paper and small-sized paper can be adjusted to 5. Since the time equivalent to A can be prevented from being exceeded, no transfer memory remains on the photoreceptor.
これらのことは以下に述べるＮ／間、Ｌ／Ｌ環境下の場
合も同様である。The same applies to the N/interval and L/L environments described below.
Ｎ／Ｎ環境下においては前記と同様、非通紙時には転写
ローラ２には、２ｇＡの定電流制御を行うものとする。Under the N/N environment, as described above, the transfer roller 2 is controlled to have a constant current of 2 gA when paper is not passing.
このとき、転写ローラ２には、４００Ｖの電圧がかかる
ことになり、この電圧をホールドして、引続く通紙時は
、１．５倍した６００ｖで定電圧制御を行うことになる
。At this time, a voltage of 400V will be applied to the transfer roller 2, and this voltage will be held and constant voltage control will be performed at 600V, which is 1.5 times higher, during subsequent paper feeding.
これによって１通紙時には、約１．３ＪＬＡの転写電流
か得られ、良好な転写性が得られることになる。As a result, a transfer current of approximately 1.3 JLA is obtained when one sheet is passed, and good transfer performance is obtained.
Ｌ／Ｌ環境下においては非通紙時、前記各場合と同様の
定電流制御を行うと、転写ローラ２に１３００Ｖの電圧
か生ずるので１通紙時に１９５０Ｖの定電圧制御を行う
。このとき、転写ローラ２には約１．８ＪＬＡの転写電
流が流れるから、良好な転写性か得られる。Under the L/L environment, when no paper passes, if constant current control similar to the above cases is performed, a voltage of 1300 V is generated at the transfer roller 2, so constant voltage control of 1950 V is performed when one paper passes. At this time, since a transfer current of about 1.8 JLA flows through the transfer roller 2, good transfer performance can be obtained.
以上説明した様に、本発明を用いることによって１本件
出願人が先に出願したＡＴ’ＶＣ制御の発明と同様に、
環境、転写材サイズにかかわらず、常時良好な転写性が
得られ、さらに、前回転や紙間の定電流制御時には、転
写メモリーによる地力ブリが発生する電流値よりも大幅
に低い電流しか流さないので、感光体や転写ローラのバ
ラツキがあっても、転写メモリーによる地力ブリが生じ
ることがなく良質の画像を得ることができる。さらに、
前回転、紙間に少ない電流しか流さないので、感光体の
帯電による劣化も少なく、感光体ドラムの長寿命化につ
ながる。As explained above, by using the present invention, similar to the AT'VC control invention previously filed by the applicant,
Good transfer performance is always achieved regardless of the environment or size of the transfer material, and in addition, during pre-rotation and constant current control between sheets, only a current that is significantly lower than the current value that causes ground force blur due to transfer memory is applied. Therefore, even if there are variations in the photoreceptor or transfer roller, high-quality images can be obtained without causing blurring due to the transfer memory. moreover,
Since only a small amount of current is passed during the pre-rotation and between the sheets, there is less deterioration due to charging of the photoreceptor, leading to a longer life of the photoreceptor drum.
また、係数Ｒを適切値にすることで、感光体や転写ロー
ラの使用上のラチチュードを広げ、プロセススピードの
速い機械に対しても、高圧の負担を軽くし、適切に対応
することかできる。例えば、フ゛ロセススビートか、２
３０ｍ論／ｓｅｃと、上記実施例の１０倍の速さをもつ
機械に対しても、係数Ｒか１であるとき１例えば通紙時
の転写電流か４０ＪＬＡ必要であるならば前回転１紙間
時に、４０ｐＡの定電流制御が必要なところを、係ｆｉ
Ｒを１．５とすることで、前回転、紙間に、転写メモリ
ーが発生する５０ｐＡより、はるかに小さい２０ｐＡの
定電流で上記実施例と同様に対応することができる。In addition, by setting the coefficient R to an appropriate value, the latitude in use of the photoreceptor and transfer roller can be expanded, and the burden of high pressure can be lightened and the load of high pressure can be reduced and appropriate support can be made for machines with high process speeds. For example, Process Beat, 2
Even for a machine with a speed of 30 m theory/sec, which is 10 times faster than the above example, if the coefficient R is 1, for example, if the transfer current during sheet passing is 40 JLA, then the pre-rotation speed is 1 sheet. Sometimes, when constant current control of 40pA is required,
By setting R to 1.5, a constant current of 20 pA, which is much smaller than the 50 pA generated by the transfer memory during the pre-rotation and between sheets, can be used in the same manner as in the above embodiment.
第４図は、本発明の他の実施態様を示すものである。FIG. 4 shows another embodiment of the invention.
この場合には、１枚出力のときには、そのつど上記実施
例で示したＡＴＶＣｉＴ制御を行うか、連続通紙のとき
には、第４図に示す様に、３枚出力毎に、定電流制御を
して、Ｖｔ値をホールドし、定電流制御時以外の紙間は
、Ｖｌ値で定電圧制御を実行している。In this case, when outputting one sheet, the ATVCiT control shown in the above embodiment is performed each time, or when continuous sheet feeding is performed, constant current control is performed every three sheets as shown in Fig. 4. The Vt value is held, and constant voltage control is performed using the Vl value during paper intervals other than during constant current control.
この様に構成しても、前記の場合と同様に全ての環境下
において、良質の画像を得られることを確認した。Even with this configuration, it was confirmed that high-quality images could be obtained under all environments, as in the case described above.
なお、この場合、定電流制御を３枚出力毎に限定するも
のでないことは勿論である。In this case, it goes without saying that the constant current control is not limited to every three sheets output.
第５図は本発明によるＡＴＶＣ制御を、レーザビームプ
リンタ、ＬＥＤプリンタ、ＬＣＳプリンタなどのプリン
タおよび、これらを利用したデジタル複写機などに適用
した場合の実施態様を示すものである。FIG. 5 shows an embodiment in which ATVC control according to the present invention is applied to printers such as laser beam printers, LED printers, and LCS printers, and digital copying machines using these printers.
このものにおいては、ＣＰＵ８にプリント信号が入力さ
れてから一定時間（同図の符号Ｘ）内に再びプリント信
号が入ると、前のプリント信号時に行つた本発明による
ＡＴＶＣ制御によってホールドした電圧を維持しつづけ
、この電圧で、あとから入力されたプリントに対する画
像出力に対しても定電圧制御を行うものとし、このよう
にプリント信号が入力されているときには、新しい信号
に対しては本発明によるＡＴＶＣ制御を行わず、ひとつ
めの信号による定電圧制御を継続する。In this device, when a print signal is input again within a certain period of time (symbol X in the figure) after the print signal is input to the CPU 8, the voltage held by the ATVC control according to the present invention performed at the time of the previous print signal is maintained. This voltage is then used to perform constant voltage control for the image output for printing that is input later.When a print signal is being input in this way, the ATVC according to the present invention is applied to a new signal. No control is performed, and constant voltage control using the first signal is continued.
時間Ｘ内に、つぎのプリント信号が入力されなかったと
きには、つぎの信号入力時に本発明によるＡＴＶＣ制御
を実行する。If the next print signal is not input within time X, the ATVC control according to the present invention is executed when the next signal is input.
このようにしても、前述の各場合と同様の効果かあり、
このものは、とくに１つの作業中で環境の変化がなくＶ
−１特性に変化がない場合に有利で、前回転時にのみ本
発明によるＡＴＶＣ制御を行なえばよい。Even if you do this, it will have the same effect as each of the above cases,
This is especially true when there are no changes in the environment during one task.
-1 It is advantageous when there is no change in the characteristic, and it is sufficient to perform the ATVC control according to the present invention only during the previous rotation.
第６図は本発明によるＡＴＶＣ制御を複写機に適用した
場合の実施態様を示すものである。FIG. 6 shows an embodiment in which ATVC control according to the present invention is applied to a copying machine.
この場合には、コピーボタンを押圧し、装置か前回転を
行なっているときに本発明によるＡＴＶＣ制御を行ない
、その後のコピー動作中は定電圧制御を行なうものとす
る。同図は、３枚コピーをとったときの制御態様を示し
ている。In this case, the ATVC control according to the present invention is performed when the copy button is pressed and the apparatus is performing pre-rotation, and the constant voltage control is performed during the subsequent copying operation. This figure shows the control mode when three copies are made.
上述した実施例では、前回転時、後回転時、紙＋１Ｊｆ
などの非通紙時で、帯電ローラ３の印加電圧が交直温間
成分ともＯＮになっている時に、本発明におけるＡＴＶ
Ｃ制御を行なったが、帯電ローラ３の印加電圧がＯＦＦ
の場合に１本発明におけるＡＴＶＣ制御を行なっても、
上記各実施例とまったく同様の効果を得ることか可渣で
ある。In the above-mentioned embodiment, during forward rotation and backward rotation, paper +1Jf
When the voltage applied to the charging roller 3 is ON for both the AC and DC warm components when the paper is not passing, such as when the paper is not passing, the ATV in the present invention
C control was performed, but the voltage applied to the charging roller 3 was OFF.
In the case of 1, even if the ATVC control according to the present invention is performed,
It is possible to obtain exactly the same effect as each of the above embodiments.
、以下説明すると、第７図の実線は、感光体の非通紙領
域で帯電ローラ３の印加電圧が交直温間成分ともＯＦＦ
のときの転写ローラ２のＶ−■特性を示している。即ち
、感光体の非帯電領域か転写位置を通過しているときの
転写ローラ２のＶ−１特性を示している。また点線は、
帯電ローラ３の印加電圧が交直温間成分ともＯＮの状態
において、Ａ４サイズの転写材が前述の転写部位を通過
する通紙時の転写ローラ２におけるＶ−１特性である。To explain below, the solid line in FIG. 7 indicates that the voltage applied to the charging roller 3 in the non-paper-passing area of the photoreceptor is both AC and DC warm components and OFF.
It shows the V-■ characteristic of the transfer roller 2 when . That is, it shows the V-1 characteristic of the transfer roller 2 when it passes through the non-charged area of the photoreceptor or the transfer position. Also, the dotted line is
This is the V-1 characteristic of the transfer roller 2 when an A4-sized transfer material passes through the above-mentioned transfer site when the voltage applied to the charging roller 3 is ON for both AC and warm components.
さらに、−点鎖線は、非通紙時で、帯電ローラ３の印加
電圧か交直温間成分ともＯＮとなっているときの転写ロ
ーラ２におけるＶ−Ｉ特性である。ここで転写ローラ２
は、上記実施例において使用したものと同じ転写ローラ
であり、第７図は、この転写ローラ２のＬ／Ｌにおける
Ｖ−Ｉ特性を示している。Furthermore, the dashed line indicates the VI characteristic of the transfer roller 2 when the paper is not passing and both the voltage applied to the charging roller 3 and the AC/DC warm component are ON. Here, transfer roller 2
is the same transfer roller as that used in the above embodiment, and FIG. 7 shows the V-I characteristic of this transfer roller 2 at L/L.
第７図より明らかな様に、帯電ローラ３の交直流内成分
がＯＦＦのときは、ＯＮのときに比べて、同一印加電圧
下での転写電流は減少する。その理由は、感光体上の電
位現象による感光体表面と電圧が印加されている転写ロ
ーラ芯金との間の電位差の現象にある。As is clear from FIG. 7, when the AC/DC component of the charging roller 3 is OFF, the transfer current under the same applied voltage is reduced compared to when it is ON. The reason for this is the phenomenon of a potential difference between the surface of the photoreceptor and the core metal of the transfer roller to which a voltage is applied due to a potential phenomenon on the photoreceptor.
第７図において、紙間において第２図と同様のＡＴＶＣ
を行なうと、帯電ローラ３の印加電圧が交直流内成分と
もＯＮのときは、Ｖｌ”は１３００Ｖとなり、係数ｔ、
Ｓを掛けてｖ２′″は１９５０Ｖとなったか、帯電ロー
ラ３の印加電圧が交直流内成分ともＯＦＦならば、Ｖ
ｌ ”’は１６５０Ｖとなり、係数１．２ テ、上記Ｖ
２”に近いＶ２”’１９８０Ｖを得られる。つまり、本
実施例においても、上記実施例と同様の効果かあり、さ
らに、係数Ｒを小さく設定することかできる０本実施例
の動作シーケンスを第８図に示しておく、ここで、上記
実施例と異なり感光体の非画像領域において帯電な０Ｆ
ＦＬ、ている状態では現像バイアスをオフしてその領域
が現像されないようにしている。In Fig. 7, the same ATVC as in Fig. 2 is shown in the paper space.
When the voltage applied to the charging roller 3 is ON for both AC and DC components, Vl'' becomes 1300V, and the coefficient t,
Multiplying by S, v2''' becomes 1950V, or if the voltage applied to the charging roller 3 is both AC and DC components OFF, V2''' becomes 1950V.
l ”' is 1650V, coefficient 1.2 te, above V
You can obtain V2'''1980V, which is close to 2''. In other words, this embodiment also has the same effect as the above embodiment, and furthermore, the coefficient R can be set small.The operation sequence of this embodiment is shown in FIG. Unlike the example, the non-image area of the photoreceptor is charged at 0F.
In the FL state, the developing bias is turned off to prevent that area from being developed.
以］−の説明では、転写用回転としてローラ形状のもの
を使用した場合について親達したか、ベルト形状のもの
を用いても良い、さらにまた、反転現像方式に限定され
るものではなく、感光体の帯電極性と反対極性のトナー
によって感光体において、露光されないで電位の高い部
分を現像する正規現像の場合にも同様の作用か得られる
ことは持ち論である。In the explanation below, we have explained that we are familiar with the case where a roller-shaped type is used as the rotation for transfer, and that a belt-shaped type can also be used. It is a matter of course that a similar effect can be obtained in the case of regular development in which areas of a photoreceptor having a high potential are developed without being exposed to light using a toner having a polarity opposite to that of the toner.
しかしながら、反転現像の場合には、感光体の帯電極性
と転写バイアスの極性が逆極性であるので特に転写バイ
アスによる帯電メモリーは生じ易くなり、本発明は有効
である。However, in the case of reversal development, since the charge polarity of the photoreceptor and the polarity of the transfer bias are opposite to each other, charge memory due to the transfer bias is particularly likely to occur, and the present invention is effective.
なお、定電流制御は、転写位置に転写材か存在しない時
間の一部に行なっても良い。Note that the constant current control may be performed during a part of the time when no transfer material is present at the transfer position.
［発明の効果］
以上説明したように、未発ＩＪｊによるときは、像担持
体とこれに対向する転写手段とをそなえた画像形成装置
において、すべての環境下で、かつ転写材のサイズの変
動にかかわらず、常時安定して良好な転写性か得られる
のて、良質の画像を得るのに顕著な効果かある。[Effects of the Invention] As explained above, in the case of undeveloped IJj, in an image forming apparatus equipped with an image bearing member and a transfer means facing the image bearing member, under all environments and with fluctuations in the size of the transfer material. Regardless of the conditions, stable and good transfer performance can be obtained at all times, which has a remarkable effect on obtaining high-quality images.
第１図は本発明を適用するに適した画像形成装置の構成
を示す概略側面図、
ｉ２図は同上の作動を示すシーケンス。
第３図は同上低温低湿（Ｌ／Ｌ）、常温常湿。
高温高湿（Ｈ／Ｈ）における転写手段のＶ−■特性を示
すグラフ、
第４図ないし第６図、第８図はそれぞれ他の制御態様を
示すシーケンス、
第７図は、像担持体の帯電状態が異なる場合の転写手段
のＶ−Ｉ特性を示すグラフ。
第９図は従来の画像形成装置の構成な略示する側面図。
第１０図は同上の動作シーケンス、
第１１図は同上における低温低湿、常温常湿。
高温高湿時の転写手段のＶ−Ｉ特性を示すグラフ、
ｌ・・・感光体
２・・・転写ローラ
３・・・帯電ローラ
４・・・高圧電源
５・・・画像情報書込手段
６・・・現像器
８・・・ＣＰＵ
である。FIG. 1 is a schematic side view showing the configuration of an image forming apparatus suitable for applying the present invention, and FIG. i2 is a sequence showing the operation of the same. Figure 3 shows the same low temperature and low humidity (L/L) as above, and normal temperature and normal humidity. Graphs showing the V-■ characteristics of the transfer means at high temperature and high humidity (H/H); Figures 4 through 6, and 8 each show sequences showing other control modes; 3 is a graph showing the VI characteristics of the transfer means when the charging state is different. FIG. 9 is a side view schematically showing the configuration of a conventional image forming apparatus. Figure 10 shows the same operation sequence as above, and Figure 11 shows the same operation sequence at low temperature and low humidity, and at room temperature and normal humidity. Graph showing the VI characteristics of the transfer means at high temperature and high humidity, l...Photoreceptor 2...Transfer roller 3...Charging roller 4...High voltage power supply 5...Image information writing means 6 ...Developer 8...CPU.
Claims (1)
形成された像を転写部位において転写材へ転写する転写
手段と、を有する画像形成装置において、少なくとも転
写部位が非画像域の時に転写手段を所定の電流値により
定電流制御し、この時転写手段に生じた電圧をＶ１とす
ると、転写偏位が画像域の時は、前記電圧値Ｖ１に所定
の係数Ｒ（Ｒ＞１）を乗じたバイアスＶ２で前記転写手
段を定電圧制御することを特徴とする画像形成装置。 ２、少なくとも前記転写部位に転写材が存在しない時に
転写手段を定電流制御し、それ以外の時に転写手段を定
電圧制御する特許請求の範囲第１項記載の画像形成装置
。 ３、少なくとも転写を行う以前に転写手段を所定の電流
値により上記定電流制御を行ってこのとき転写手段に生
した電圧をＶ１とし、以後出力画像数が所定数に達する
まで、転写部位が画像域の時は前記電圧値Ｖ１に所定の
係数Ｒを乗じた電圧Ｖ２で転写部位が非画像域の時は、
前記電圧値Ｖ１で、定電圧制御を行う特許請求の範囲第
１項記載の画像形成装 置。 ４、少なくとも転写を行う以前に転写手段を所定の電流
値により定電流制御してその時の電圧値をＶ１とし、以
後、出力画像数が所定数に達するまで、転写部位が画像
域の時は、前記電圧値Ｖ１に予め決められた係数Ｒを乗
じた電圧Ｖ２で、転写部位が非画像域の時は、前記電圧
値Ｖ１で定電圧制御を行い、所定カウントに達したら上
記の工程をくり返し行う特許請求の範囲第１項記載の画
像形成装置。 ５、転写手段が転写ローラである特許請求の範囲第１項
記載の画像形成装置。 ６、転写手段が転写ベルトである特許請求の範囲第１項
記載の画像形成装置。[Scope of Claims] 1. An image forming apparatus including an image carrier and a transfer means that faces the image carrier and transfers an image formed on the surface of the image carrier to a transfer material at a transfer site, At least when the transfer site is in a non-image area, the transfer means is controlled with a constant current value using a predetermined current value, and if the voltage generated in the transfer means at this time is V1, when the transfer deviation is in the image area, the voltage value V1 is An image forming apparatus characterized in that the transfer means is controlled at a constant voltage by a bias V2 multiplied by a predetermined coefficient R (R>1). 2. The image forming apparatus according to claim 1, wherein the transfer means is controlled with a constant current at least when no transfer material is present at the transfer site, and the transfer means is controlled with a constant voltage at other times. 3. At least before performing the transfer, perform the above-mentioned constant current control on the transfer means with a predetermined current value, and set the voltage generated in the transfer means at this time to V1, and from then on until the number of output images reaches the predetermined number, the transfer portion is in the image state. When the transfer area is a non-image area, the voltage V2 is obtained by multiplying the voltage value V1 by a predetermined coefficient R.
The image forming apparatus according to claim 1, wherein constant voltage control is performed at the voltage value V1. 4. At least before performing the transfer, the transfer means is controlled with a constant current value using a predetermined current value, and the voltage value at that time is set to V1. From then on, until the number of output images reaches the predetermined number, when the transfer site is in the image area, A voltage V2 is obtained by multiplying the voltage value V1 by a predetermined coefficient R. When the transfer site is in a non-image area, constant voltage control is performed using the voltage value V1, and when a predetermined count is reached, the above steps are repeated. An image forming apparatus according to claim 1. 5. The image forming apparatus according to claim 1, wherein the transfer means is a transfer roller. 6. The image forming apparatus according to claim 1, wherein the transfer means is a transfer belt.
Priority Applications (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1085189A JP2614309B2 (en) | 1989-04-03 | 1989-04-03 | Image forming device |
| US07/500,795 US5179397A (en) | 1989-04-03 | 1990-03-28 | Image forming apparatus with constant voltage and constant current control |
| EP90106276A EP0391306B1 (en) | 1989-04-03 | 1990-04-02 | An image forming apparatus |
| DE69020770T DE69020770T2 (en) | 1989-04-03 | 1990-04-02 | Imaging device. |
| ES90106276T ES2074097T3 (en) | 1989-04-03 | 1990-04-02 | APPARATUS FOR THE FORMATION OF IMAGES. |
| CN 90101841 CN1032034C (en) | 1989-04-03 | 1990-04-03 | Picture forming apparatus |
| KR1019900004592A KR930010873B1 (en) | 1989-04-03 | 1990-04-03 | Image forming apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1085189A JP2614309B2 (en) | 1989-04-03 | 1989-04-03 | Image forming device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02264278A true JPH02264278A (en) | 1990-10-29 |
| JP2614309B2 JP2614309B2 (en) | 1997-05-28 |
Family
ID=13851711
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1085189A Expired - Lifetime JP2614309B2 (en) | 1989-04-03 | 1989-04-03 | Image forming device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2614309B2 (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5436701A (en) * | 1992-06-19 | 1995-07-25 | Canon Kabushiki Kaisha | Image forming method, image forming apparatus and apparatus unit |
| JP2003057969A (en) * | 2001-08-09 | 2003-02-28 | Canon Inc | Image forming device |
| US7031624B2 (en) | 2002-10-21 | 2006-04-18 | Canon Kabushiki Kaisha | Image formation apparatus for providing a predetermined temperature lowering period in which the temperature of a fixing unit is reduced |
| US7684717B2 (en) | 2006-02-28 | 2010-03-23 | Kabushiki Kaisha Toshiba | Image forming apparatus and image forming method |
| JP2010191276A (en) * | 2009-02-19 | 2010-09-02 | Canon Inc | Image forming apparatus |
| US8107834B2 (en) | 2006-04-19 | 2012-01-31 | Kabushiki Kaisha Toshiba | Image forming apparatus and control method for the same |
| US8200109B2 (en) | 2008-09-08 | 2012-06-12 | Canon Kabushiki Kaisha | Image forming apparatus |
| US11009815B2 (en) | 2018-12-28 | 2021-05-18 | Canon Kabushiki Kaisha | Image forming apparatus with control of power to transfer roller |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4227446B2 (en) * | 2003-03-27 | 2009-02-18 | キヤノン株式会社 | Image forming apparatus |
-
1989
- 1989-04-03 JP JP1085189A patent/JP2614309B2/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5436701A (en) * | 1992-06-19 | 1995-07-25 | Canon Kabushiki Kaisha | Image forming method, image forming apparatus and apparatus unit |
| JP2003057969A (en) * | 2001-08-09 | 2003-02-28 | Canon Inc | Image forming device |
| US7031624B2 (en) | 2002-10-21 | 2006-04-18 | Canon Kabushiki Kaisha | Image formation apparatus for providing a predetermined temperature lowering period in which the temperature of a fixing unit is reduced |
| CN100338536C (en) * | 2002-10-21 | 2007-09-19 | 佳能株式会社 | Image forming device |
| US7684717B2 (en) | 2006-02-28 | 2010-03-23 | Kabushiki Kaisha Toshiba | Image forming apparatus and image forming method |
| US8107834B2 (en) | 2006-04-19 | 2012-01-31 | Kabushiki Kaisha Toshiba | Image forming apparatus and control method for the same |
| US8200109B2 (en) | 2008-09-08 | 2012-06-12 | Canon Kabushiki Kaisha | Image forming apparatus |
| JP2010191276A (en) * | 2009-02-19 | 2010-09-02 | Canon Inc | Image forming apparatus |
| US11009815B2 (en) | 2018-12-28 | 2021-05-18 | Canon Kabushiki Kaisha | Image forming apparatus with control of power to transfer roller |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2614309B2 (en) | 1997-05-28 |
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