JPH07107620B2 - Multiple image forming device - Google Patents
Multiple image forming deviceInfo
- Publication number
- JPH07107620B2 JPH07107620B2 JP61125141A JP12514186A JPH07107620B2 JP H07107620 B2 JPH07107620 B2 JP H07107620B2 JP 61125141 A JP61125141 A JP 61125141A JP 12514186 A JP12514186 A JP 12514186A JP H07107620 B2 JPH07107620 B2 JP H07107620B2
- Authority
- JP
- Japan
- Prior art keywords
- transfer
- transfer material
- image
- color
- carrier
- 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.)
- Expired - Lifetime
Links
Description
【発明の詳細な説明】 〔産業上の利用範囲〕 本発明は回動する転写材担持シート上に転写材を担持
し、転写材担持シート上の転写材に転写電界を付与して
感光ドラムや絶縁ドラム等の像担持体上に順次形成され
る複数のトナー像を転写材上に順次重ねて転写を行う装
置例えばカラー複写機やカラープリント等に適用できる
転写工程を有する多重画像形成装置に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION [Industrial range of application] The present invention supports a transfer material on a rotating transfer material carrying sheet, and applies a transfer electric field to the transfer material on the transfer material carrying sheet to form a photosensitive drum or a photosensitive drum. A multiple image forming apparatus having a transfer step applicable to a device for sequentially superposing a plurality of toner images sequentially formed on an image bearing member such as an insulating drum on a transfer material, for example, a color copying machine or a color print. Is.
第３図は、従来のカラー画像形成装置の概略図であり、
像担持体である感光ドラム１をコロナ放電器２により所
定極性に帯電した後、情報露光Ｉを与え、静電潜像を形
成し、その潜像を現像器3a,3b,3cのうち所定色のトナー
を有する現像器により現像する。一方転写ドラム４は、
第４図にその斜視図を示すように、シリンダ枠41と転写
材先端を把持するグリツパ42とシリンダ枠41の周面開口
域に張設される絶縁性フイルムあるいは絶縁性メツシユ
スクリーンなどの転写材担持シート43から成り、給送さ
れた転写材の先端をグリツパ42で把持して、転写材を担
持シートに巻付けた後、転写コロナ放電器５により感光
ドラム１上のトナー像を転写材上に転写すると共に、転
写材を転写材担持シート上に静電吸着させる。次に感光
ドラム１上に異なる情報露光に基づく潜像を形成し、所
定色の現像器により現像し、得られたトナー像を転写材
上に、先に転写されたトナー像に位置合せして転写す
る。こうして３色のトナー像の転写が終了し、転写材の
先端が分離位置に近づくとグリツパ42が解除され、かつ
分離爪10が転写ドラム４へ接近し、転写材担持シート上
の転写材が分離される。このとき同時に、転写材担持シ
ートを挟んで設けられた２つのコロナ放電器８及び９に
交流電圧が印加され、転写材表面と担持シート裏面の除
電が行なわれる。FIG. 3 is a schematic view of a conventional color image forming apparatus,
After the photosensitive drum 1 as an image carrier is charged to a predetermined polarity by the corona discharger 2, information exposure I is applied to form an electrostatic latent image, and the latent image is formed in a predetermined color among the developing devices 3a, 3b, 3c. It is developed by a developing device having the above toner. On the other hand, the transfer drum 4 is
As shown in the perspective view in FIG. 4, the transfer of an insulating film or an insulating mesh screen stretched over the opening of the cylinder frame 41, the gripper 42 for gripping the transfer material tip, and the peripheral surface of the cylinder frame 41 is performed. The transfer material is composed of a material-carrying sheet 43. The front end of the fed transfer material is gripped by the gripper 42, the transfer material is wound around the carrier sheet, and the toner image on the photosensitive drum 1 is transferred by the transfer corona discharger 5. The transfer material is electrostatically adsorbed on the transfer material carrying sheet while being transferred onto the transfer material. Next, a latent image based on different information exposure is formed on the photosensitive drum 1 and developed by a developing device of a predetermined color, and the obtained toner image is aligned on the transfer material with the previously transferred toner image. Transcribe. In this way, when the transfer of the three color toner images is completed and the tip of the transfer material approaches the separation position, the gripper 42 is released, the separation claw 10 approaches the transfer drum 4, and the transfer material on the transfer material carrying sheet is separated. To be done. At this time, at the same time, an AC voltage is applied to the two corona dischargers 8 and 9 provided on both sides of the transfer material carrying sheet, and the surface of the transfer material and the back surface of the carrying sheet are neutralized.
このコロナ放電器８及び９による除電は、転写材と担持
シートとの静電吸着力の除去及び転写材分離時の気中放
電によるトナー像の飛散を防止することが目的である。The purpose of the charge removal by the corona dischargers 8 and 9 is to remove the electrostatic attraction force between the transfer material and the carrying sheet and to prevent the toner image from scattering due to the air discharge at the time of separating the transfer material.
かくして、転写材が分離された後、搬送ベルト11により
転写材が定着器に搬送され、加熱定着され、カラー画像
が得られるものである。ところが、従来次のような問題
があった。In this way, after the transfer material is separated, the transfer material is conveyed to the fixing device by the conveyor belt 11 and heat-fixed to obtain a color image. However, there have been the following problems conventionally.
即ち、感光ドラム１である像担持体上に順次形成される
複数色のトナー像を、転写材担持シート上の転写材に順
次重ね転写を行った場合、１色目のトナーの転写率に比
べ２色目、３色目と転写を重ねるに従って転写率が低下
する現像が生じ、問題であった。この現像の主な原因
は、転写後転写材が像担持体から離れるとき転写材表面
が転写コロナ放電電荷と逆極性に帯電し、またその帯電
電荷が転写毎に蓄積することによるものと考えられる。That is, when toner images of a plurality of colors that are sequentially formed on the image bearing member, which is the photosensitive drum 1, are sequentially transferred onto the transfer material on the transfer material bearing sheet, the transfer rate is 2 compared to the transfer rate of the toner of the first color. This is a problem because development occurs in which the transfer rate decreases as the transfer of the third color and the third color is repeated. It is considered that the main cause of this development is that the surface of the transfer material is charged with a polarity opposite to that of the transfer corona discharge charge when the transfer material is separated from the image carrier after the transfer, and the charged charge is accumulated for each transfer. .
従来、この問題に対処するのに、コロナ放電器８及び９
により、転写毎に転写材表面と転写材担持シート裏面の
電荷の除電を行う方法が提案されている。しかしコロナ
放電器８及び９により転写毎に除電を行った場合、転写
材の担持シートに対する静電吸着力が低下し、各色トナ
ー像の間で色ずれが生じたり、甚だしい場合は、転写材
が担持シートから剥離して、転写ドラム周辺の構造物、
例えば分離爪や転写材ガイドに接触し、転写材上に転写
されたトナー像の欠落が生じたりして実用に耐えない問
題があった。Conventionally, to address this problem, corona dischargers 8 and 9 have been used.
Has proposed a method of removing charges on the surface of the transfer material and the back surface of the transfer material carrying sheet for each transfer. However, when the charge is removed by the corona dischargers 8 and 9 for each transfer, the electrostatic attraction force of the transfer material to the carrying sheet is reduced, and color shift occurs between the toner images of the respective colors. The structure around the transfer drum is peeled off from the carrier sheet,
For example, there is a problem that the toner image transferred onto the transfer material may come into contact with the separation claw or the transfer material guide and may be unusable for practical use.
本発明は、上述のような問題点を除去することであり、
複数色のトナー像を順次転写材上に転写する際の転写毎
の転写率低下および色ずれを防止することができる転写
工程を有する画像形成装置を提供することを目的とす
る。The present invention is to eliminate the above problems,
An object of the present invention is to provide an image forming apparatus having a transfer step capable of preventing a decrease in transfer rate and color misregistration at each transfer when toner images of a plurality of colors are sequentially transferred onto a transfer material.
以上の目的を達成するための本発明は、像を担持する像
担持体と、この像担持体の転写部に転写材を担持搬送す
る転写材担持体と、前記転写部において、前記転写材担
持体に担持された前記転写材に前記像担持体の像を転写
する転写帯電器と、を備え、前記転写材に前記像を順次
重ねて転写する多重画像形成装置において、前記転写材
担持体の転写材搬送方向上流側であって、前記転写部に
対向する位置に前記転写帯電器の極性と同極性の除電器
を設け、この除電器は、像が転写された前記転写材と前
記像担持体が担持する像を除電することを特徴とするも
のである。The present invention for achieving the above object includes an image carrier that carries an image, a transfer material carrier that carries and conveys a transfer material to a transfer portion of the image carrier, and the transfer material carrier in the transfer portion. In a multiple image forming apparatus, comprising: a transfer charger that transfers an image of the image carrier onto the transfer material carried on a body, and sequentially transferring the images onto the transfer material, A charge eliminator having the same polarity as that of the transfer charger is provided at a position facing the transfer portion on the upstream side in the transfer material conveyance direction, and the charge eliminator includes the transfer material on which an image is transferred and the image carrier. It is characterized in that the image carried by the body is eliminated.
以下、本発明の関連技術について第１図に示すカラー画
像形成装置に基いて説明し、また、本発明の実施例を第
２図に示すカラー画像形成装置に基いて説明する。Hereinafter, the related art of the present invention will be described based on the color image forming apparatus shown in FIG. 1, and the embodiment of the present invention will be described based on the color image forming apparatus shown in FIG.
第１図及び第２図において、第３図と共通なものは同一
の数字で示し、また前記従来例におけるカラー画像形成
工程と同じ説明は省略する。In FIG. 1 and FIG. 2, the same parts as those in FIG. 3 are indicated by the same numerals, and the same explanation as the color image forming step in the above-mentioned conventional example is omitted.
第１図において、除電器としてのコロナ放電器12が、少
なくとも転写ドラム４のグリツパが転写材先端を把持す
る位置Ａの下流であって転写位置の直前の位置に設けら
れている。またコロナ放電器12の放電効率を増す為に接
地された対向電極13が転写材シートを挟んで転写ドラム
内側に設けられている。コロナ放電器12は、転写材上に
１色目のトナー像が転写された後、２色目のトナー像を
重ねて転写される直前にコロナ放電が開始され、転写材
上の電荷を所定量除電する。コロナ放電器12に印加する
高圧は交流電圧または転写コロナ放電電荷と同極性の直
流電圧または除電量を制御する為の直流バイアス電圧が
重畳された交流電圧が用いられている。In FIG. 1, a corona discharger 12 as a static eliminator is provided at a position at least downstream of the position A where the gripper of the transfer drum 4 grips the front end of the transfer material and immediately before the transfer position. Further, a counter electrode 13 which is grounded to increase the discharge efficiency of the corona discharger 12 is provided inside the transfer drum with the transfer material sheet interposed therebetween. The corona discharger 12 starts corona discharge immediately after the toner image of the first color is transferred onto the transfer material and immediately before the toner images of the second color are overlaid and discharges a predetermined amount of charge on the transfer material. . The high voltage applied to the corona discharger 12 is an AC voltage or a DC voltage having the same polarity as the transferred corona discharge charge or an AC voltage on which a DC bias voltage for controlling the amount of static electricity is superimposed.
コロナ放電器12による放電は、少なくとも、３色目、４
色のトナー像を転写する装置において４色目のトナー像
が重ねて転写される前の転写材上の除電が終了するまで
継続される。コロナ放電器12に印加する電圧は一定電圧
でも良いが、２色目の転写前除電における印加電圧に較
べ３色目の転写前除電の能力を段階的に高めた方がより
効果的である。例えばコロナ放電器12に印加する交流電
圧を２色目の転写前除電時に4.5KV、３色目の転写前除
電時に5.0KVに制御するか、あるいは同様に交流電圧5.0
KV一定として、重畳するバイアス電圧を順に−0.8KV、
−0.4KVに制御する。The corona discharger 12 discharges at least the third color and the fourth color.
In the apparatus for transferring the color toner images, the charge removal is continued until the charge removal on the transfer material before the fourth color toner images are transferred in an overlapping manner. The voltage applied to the corona discharger 12 may be a constant voltage, but it is more effective to increase the capability of the pre-transfer charge elimination for the third color stepwise as compared with the applied voltage for the pre-transfer charge elimination for the second color. For example, the AC voltage applied to the corona discharger 12 is controlled to 4.5 KV when the second color is neutralized before transfer, or to 5.0 KV when the third color is neutralized before transfer, or in the same manner, the AC voltage is 5.0 KV.
Assuming that KV is constant, the bias voltage to be superimposed is -0.8KV in order,
Control to −0.4KV.
なお、対向電極13に代えてコロナ放電器を設けて転写材
担持体としての転写材担持シートの裏面の電荷の除去を
行っても良いのは勿論である。Of course, instead of the counter electrode 13, a corona discharger may be provided to remove charges on the back surface of the transfer material carrying sheet as the transfer material carrying body.
上記のようなコロナ放電器12による転写材上の電荷の除
電を行うことにより、転写材の担持シートに対する静電
吸着力が低下する領域の面積は、コロナ放電器12の照射
域から転写コロナ放電器５の照射域までの小面積に留ま
り、転写材全体の担持シートに対する静電吸着力の低下
を最小限に抑えることができ、この結果、色ずれの発生
を防止することができる。By removing the charge on the transfer material by the corona discharger 12 as described above, the area of the area where the electrostatic adsorption force on the carrier sheet of the transfer material decreases is the transfer corona discharge from the irradiation area of the corona discharger 12. It can be kept in a small area up to the irradiation area of the electric device 5, and the decrease in the electrostatic attraction force of the entire transfer material to the carrying sheet can be suppressed to a minimum, and as a result, the occurrence of color misregistration can be prevented.
また、第２図は本発明の実施例を示すカラー画像形成装
置である。FIG. 2 is a color image forming apparatus showing an embodiment of the present invention.
第２図において、除電器としてのコロナ放電器14が少な
くともＡの下流側であって転写位置の直前の位置に設け
られている。13はコロナ放電器14の対向電極である。In FIG. 2, a corona discharger 14 as a static eliminator is provided at least on the downstream side of A and immediately before the transfer position. Reference numeral 13 is a counter electrode of the corona discharger 14.
コロナ放電器14は転写部に向けてコロナ放電が行われる
ように設けられ、高圧印加タイミングは前述した関連技
術の場合と同じで、転写材上の電荷の除電を行うが、そ
れと共にトナー像を担持した感光ドラム１上の電荷を除
電する。この感光ドラム１上の除電はトナーの電荷を除
電して既に転写材上に転写されているトナーとの反発力
を低下させると共に、トナーを保持している潜像電荷を
除電してトナーの拘束力を低下させ、多重転写効率の低
下を防止するためであり、１個のコロナ放電器により転
写材上及び感光ドラム上の電荷を除電することができ、
それぞれの除電の為の２個のコロナ放電器を設ける場合
に較べ空間的な配置上の制約の点で有利であり、また構
成が簡単になる。なおこの感光ドラム上の電荷の除電の
際、カラートナーに対する光透過率の高い近赤外光を照
射するとトナーを通して感光ドラム上の潜像電荷が光減
衰してより効果的な除電が可能となる。The corona discharger 14 is provided so as to perform corona discharge toward the transfer portion, and the high voltage application timing is the same as in the case of the related art described above. The charges on the carried photosensitive drum 1 are removed. The charge removal on the photosensitive drum 1 removes the charge of the toner to reduce the repulsive force with the toner already transferred onto the transfer material, and also removes the latent image charge holding the toner to restrain the toner. This is to reduce the force and prevent the reduction of the multiple transfer efficiency, and the charge on the transfer material and the photosensitive drum can be removed by one corona discharger.
Compared with the case of providing two corona dischargers for each charge elimination, it is advantageous in terms of spatial arrangement, and the configuration is simple. When the charge on the photosensitive drum is discharged, if the near-infrared light having a high light transmittance with respect to the color toner is irradiated, the latent image charge on the photosensitive drum is attenuated through the toner, so that the charge can be removed more effectively. .
なお第１図のコロナ放電器12及び第２図のコロナ放電器
13のシールド部材あるいはその近傍に、転写材の後端が
はね上って放電ワイヤに接触しないよう、開口部に絶縁
性の糸を張りめぐらしたり、あるいは、数個の滑車を設
けたりしても良い。The corona discharger 12 shown in FIG. 1 and the corona discharger shown in FIG.
To prevent the rear end of the transfer material from splashing up and coming into contact with the discharge wire, shield wire of 13 or around it is provided with insulating thread or several pulleys. Is also good.
従って、本発明の多重画像形成装置では、転写材担持体
の転写材搬送方向上流側であって、転写部に対向する位
置に転写帯電器の極性と同極性の除電器を設け、この除
電器が、像が転写された転写材を除電するため、転写毎
の転写効率の低下を防止するとともに、転写材の転写材
担持体に対する静電吸着力の低下する領域を最小限に抑
えることができ、この結果、色ずれのない良好な多重画
像を得ることが可能となる。また、この除電器は像担持
体が担持する像を同時に除電するため、転写材上の像と
像担持体が担持する像との反発力を低下させるととも
に、転写効率の低下を防止することが可能となる。さら
に、除電器の数を減らすことができ配置上有利となる。Therefore, in the multiplex image forming apparatus of the present invention, a static eliminator having the same polarity as the polarity of the transfer charger is provided on the upstream side of the transfer material carrier in the transfer material transport direction and at a position facing the transfer portion. However, since the transfer material on which the image has been transferred is neutralized, it is possible to prevent the transfer efficiency from decreasing for each transfer and to minimize the area where the electrostatic attraction of the transfer material to the transfer material carrier decreases. As a result, it is possible to obtain a good multiplex image without color shift. Further, since this static eliminator removes static electricity from the image carried by the image carrier at the same time, it is possible to reduce the repulsive force between the image on the transfer material and the image carried by the image carrier and prevent the transfer efficiency from being lowered. It will be possible. Furthermore, the number of static eliminators can be reduced, which is advantageous in terms of arrangement.
第１図は本発明の関連技術の説明図、第２図は本発明の
カラー画像形成装置の要部説明図、第３図は従来装置の
要部説明図、第４図は第１図〜第３図に示す転写ドラム
の斜視図である。 １……感光ドラム、２……コロナ放電器、3a,3b,3c……
現像器、４……転写ドラム、５……転写コロナ放電器、
8,9……分離除電用コロナ放電器、10……分離爪、12,14
……コロナ放電器、13……対向電極。FIG. 1 is an explanatory view of a related art of the present invention, FIG. 2 is an explanatory view of a main part of a color image forming apparatus of the present invention, FIG. 3 is an explanatory view of a main part of a conventional apparatus, and FIG. FIG. 4 is a perspective view of the transfer drum shown in FIG. 3. 1 ... Photosensitive drum, 2 ... Corona discharger, 3a, 3b, 3c ...
Developing device, 4 ... Transfer drum, 5 ... Transfer corona discharger,
8,9 …… Separation static elimination corona discharger, 10 …… Separation claw, 12,14
...... Corona discharger, 13 ...... Counter electrode.
Claims (1)
転写部に転写材を担持搬送する転写材担持体と、前記転
写部において、前記転写材担持体に担持された前記転写
材に前記像担持体の像を転写する転写帯電器と、を備
え、前記転写材に前記像を順次重ねて転写する多重画像
形成装置において、 前記転写材担持体の転写材搬送方向上流側であって、前
記転写部に対向する位置に前記転写帯電器の極性と同極
性の除電器を設け、この除電器は、像が転写された前記
転写材と前記像担持体が担持する像を除電することを特
徴とする多重画像形成装置。1. An image carrier that carries an image, a transfer material carrier that carries and conveys a transfer material to a transfer portion of the image carrier, and the transfer carried by the transfer material carrier at the transfer portion. In a multiple image forming apparatus, comprising: a transfer charger that transfers the image of the image carrier to a material, and sequentially transferring the images to the transfer material in a superimposing manner. A static eliminator having the same polarity as the polarity of the transfer charger is provided at a position facing the transfer portion, and the static eliminator neutralizes the image carried by the transfer material on which the image is transferred and the image carrier. A multiple image forming apparatus characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61125141A JPH07107620B2 (en) | 1986-05-30 | 1986-05-30 | Multiple image forming device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61125141A JPH07107620B2 (en) | 1986-05-30 | 1986-05-30 | Multiple image forming device |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6086384A Division JPH0827569B2 (en) | 1994-04-25 | 1994-04-25 | Multiple image forming device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62280873A JPS62280873A (en) | 1987-12-05 |
| JPH07107620B2 true JPH07107620B2 (en) | 1995-11-15 |
Family
ID=14902875
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61125141A Expired - Lifetime JPH07107620B2 (en) | 1986-05-30 | 1986-05-30 | Multiple image forming device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07107620B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01282571A (en) * | 1988-05-10 | 1989-11-14 | Sharp Corp | Color electrophotographic copying device |
| JPH0371355U (en) * | 1989-11-17 | 1991-07-18 | ||
| KR20080071612A (en) * | 2005-12-26 | 2008-08-04 | 가부시끼가이샤 도시바 | Pattern forming apparatus and pattern forming method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6029947B2 (en) * | 1976-12-14 | 1985-07-13 | 株式会社リコー | Transfer method for multicolor electrophotography |
| JPS5538525A (en) * | 1978-09-12 | 1980-03-18 | Ricoh Co Ltd | Transfer method of multicolor electrophotographic copier |
| JPS60169862A (en) * | 1984-02-13 | 1985-09-03 | Japan Steel Works Ltd:The | Multicolor electrophotographic apparatus |
-
1986
- 1986-05-30 JP JP61125141A patent/JPH07107620B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62280873A (en) | 1987-12-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |