JP2000214661A - Contact electrifying device for image forming device - Google Patents
Contact electrifying device for image forming deviceInfo
- Publication number
- JP2000214661A JP2000214661A JP11014583A JP1458399A JP2000214661A JP 2000214661 A JP2000214661 A JP 2000214661A JP 11014583 A JP11014583 A JP 11014583A JP 1458399 A JP1458399 A JP 1458399A JP 2000214661 A JP2000214661 A JP 2000214661A
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- Prior art keywords
- contact charging
- frequency
- voltage
- charging device
- image forming
- 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.)
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- Electrostatic Charge, Transfer And Separation In Electrography (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、電子写真システ
ムを採用した画像形成装置に関し、特に接触帯電ローラ
に定電流制御した交流電圧と定電圧制御した直流電圧と
を重畳して印加する接触帯電装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus employing an electrophotographic system, and more particularly to a contact charging device for applying a constant current controlled AC voltage and a constant voltage controlled DC voltage to a contact charging roller in a superimposed manner. About.
【０００２】[0002]
【従来の技術】電子写真システムを採用した画像形成装
置には、一般に、像担持体に一様に帯電を施す帯電装置
が配設されている。2. Description of the Related Art An image forming apparatus employing an electrophotographic system is generally provided with a charging device for uniformly charging an image carrier.
【０００３】この従来の画像形成装置の帯電装置には、
像担持体を圧接する接触帯電ローラと、該接触帯電ロー
ラに電圧を印加するバイアス印加手段とを具え、該バイ
アス印加手段を介し接触帯電ローラにより像担持体表面
に帯電を施すようにした接触帯電装置がある。The charging device of this conventional image forming apparatus includes:
A contact charging roller that presses the image carrier, and a bias applying unit that applies a voltage to the contact charging roller; and a contact charging unit that charges the surface of the image carrier by the contact charging roller via the bias applying unit. There is a device.
【０００４】この従来の接触帯電装置１は、その概念構
成図で示す図８のように、回転駆動する像担持体３と、
像担持体３に圧接する接触帯電ローラ４と、該接触帯電
ローラ４に定電流制御した交流電圧と定電圧制御した直
流電圧とを重畳して印加するバイアス印加手段１３とか
ら構成されている。[0004] As shown in a conceptual configuration diagram of FIG. 8, this conventional contact charging device 1 includes an image carrier 3 that is driven to rotate,
The contact charging roller 4 is pressed against the image carrier 3, and a bias applying unit 13 is configured to apply a constant current controlled AC voltage and a constant voltage controlled DC voltage to the contact charging roller 4 in a superimposed manner.
【０００５】このうち、接触帯電ローラ４は弾性部材か
ら構成され、その要部拡大断面図で示す図９のように幅
ｗのニップで像担持体３に圧接している。なお、図９で
は、図８と同一部分を同一符号で示している。The contact charging roller 4 is formed of an elastic member, and is in pressure contact with the image carrier 3 with a nip having a width w as shown in FIG. In FIG. 9, the same parts as those in FIG. 8 are denoted by the same reference numerals.
【０００６】また、この従来の接触帯電装置１ではバイ
アス印加手段１３は、図８で示すように、交流電圧を定
電流制御する定電流回路１４と、直流電圧を定電圧制御
する定電圧回路１８と、定電流回路１４により制御され
た交流電圧と定電圧回路１８により制御された直流電圧
とを重畳して接触帯電ローラ４に印加する重畳印加手段
１９とから構成される。Further, in the conventional contact charging device 1, as shown in FIG. 8, a bias applying means 13 includes a constant current circuit 14 for controlling an AC voltage with a constant current and a constant voltage circuit 18 for controlling a DC voltage with a constant voltage. And a superimposing means 19 for superimposing an AC voltage controlled by the constant current circuit 14 and a DC voltage controlled by the constant voltage circuit 18 and applying the superposed voltage to the contact charging roller 4.
【０００７】このうち、定電流回路１４は、交流電圧を
発生する正弦波発生手段１５と、正弦波発生手段１５に
より発生した交流電圧を増幅して重畳印加手段１９に送
出する電圧増幅手段１６と、重畳印加手段１９による印
加により像担持体４に流れる電流を検知する電流検知手
段１７とから構成されており、電圧増幅手段１６は電流
検知手段１７により検知された電流の周波数成分に基づ
き直接電圧増幅率を変更して交流電圧を増幅する。The constant current circuit 14 includes a sine wave generating means 15 for generating an AC voltage, a voltage amplifying means 16 for amplifying the AC voltage generated by the sine wave generating means 15 and sending the amplified voltage to the superimposing means 19. A current detecting means 17 for detecting a current flowing through the image carrier 4 by application by the superimposing applying means 19, and a voltage amplifying means 16 directly outputs a voltage based on a frequency component of the current detected by the current detecting means 17. The AC voltage is amplified by changing the amplification factor.
【０００８】また、電圧増幅率制御では、周波数とゲイ
ンの関係を示す図１０のように、ノイズとされる高周波
数域を除き、電流検知手段１７により検知された電流の
周波数成分は、どのような周波数成分のものについても
一律に応答させている。In the voltage amplification factor control, as shown in FIG. 10 showing the relationship between the frequency and the gain, the frequency components of the current detected by the current detecting means 17 are different except for a high frequency region which is regarded as noise. The response is also uniform for the components having the various frequency components.
【０００９】このような従来の接触帯電装置１では、接
触帯電ローラ４に、バイアス印加手段１３により定電流
制御した交流電圧と定電圧制御した直流電圧とを重畳し
て印加すると、接触帯電ローラ４のニップ前後で（＋）
／（−）の交互放電が起こり、像担持体３の表面３ａは
最終的に直流電圧成分の電圧近くの電圧値に収束し、一
様に帯電する。In such a conventional contact charging device 1, when an AC voltage controlled by a constant current and a DC voltage controlled by a constant voltage are applied to the contact charging roller 4 in a superimposed manner, the contact charging roller 4 Before and after the nip (+)
An alternating discharge of / (-) occurs, and the surface 3a of the image carrier 3 finally converges to a voltage value near the voltage of the DC voltage component and is uniformly charged.
【００１０】一方、この従来の接触帯電装置１を具えた
画像形成装置２では、図８で示すように、接触帯電装置
１により一様に帯電された像担持体３の表面３ａに、露
光手段５により画像を露光して静電潜像を形成し、さら
に該静電潜像を現像手段６により現像してトナー像を形
成し、該トナー像を転写手段７によって転写材８に転写
し、これにより転写材８に画像を出力するようにしてい
る。On the other hand, in the image forming apparatus 2 provided with the conventional contact charging device 1, as shown in FIG. 8, the surface 3a of the image carrier 3, which is uniformly charged by the contact charging device 1, is exposed to an exposure means. 5, an electrostatic latent image is formed by exposing the image, and the electrostatic latent image is further developed by a developing unit 6 to form a toner image, and the toner image is transferred to a transfer material 8 by a transfer unit 7. Thus, an image is output on the transfer material 8.
【００１１】また、この従来の接触帯電装置１では、バ
イアス印加手段１３は、図８で示すように、交流電圧を
定電流制御する定電流回路１４と、直流電圧を定電圧制
御する定電圧回路１８と、定電流回路１４により制御さ
れた交流電圧と定電圧回路１８により制御された直流電
圧とを重畳して接触帯電ローラ４に印加する重畳印加手
段１９とから構成され、その定電流回路１４では、電流
検知手段１７により検知された電流の周波数成分に基づ
いて、図１０で示すようにノイズとされる高周波数域を
除きどのような周波数成分のものについても一律に応答
させて電圧増幅率制御することとしているから、これに
より、接触帯電ローラ４の抵抗むらがある場合でも過大
な電圧を印加することなく放電に必要な電圧を印加する
ことが可能となり、また環境によって接触帯電ローラ４
の抵抗が変化するような場合でも帯電むらが生じること
を可及的に防止している。Further, in the conventional contact charging device 1, as shown in FIG. 8, a bias applying means 13 includes a constant current circuit 14 for controlling an AC voltage with a constant current, and a constant voltage circuit for controlling a DC voltage with a constant voltage. And a superimposing means 19 for superimposing the AC voltage controlled by the constant current circuit 14 and the DC voltage controlled by the constant voltage circuit 18 and applying the superposed voltage to the contact charging roller 4. Then, based on the frequency component of the current detected by the current detecting means 17, the voltage amplification factor is made to uniformly respond to any frequency component except for a high frequency region which is regarded as noise as shown in FIG. As a result, it is possible to apply a voltage necessary for discharging without applying an excessive voltage even when the contact charging roller 4 has uneven resistance. The contacted by environmental charging roller 4
Is prevented as much as possible even when the resistance changes.
【００１２】[0012]
【発明が解決しようとする課題】ところで、上述した従
来の接触帯電装置１によると、像担持体３に幅ｗのニッ
プで圧接する接触帯電ローラ４は弾性体から構成されて
いるから、画像形成装置を長時間停止させた状態にする
と、図９と同一部分を同一符号で示す図１１のように、
接触帯電ローラ４には像担持体を圧接し続けたことによ
って、ニップによる凹み４ａが画像形成装置２の駆動後
にもその一部に依然として残り、そのため、像担持体３
は凹み４ａのある接触帯電ローラ４により帯電すること
となるが、バイアス印加手段１３では定電流制御した交
流電圧を定電圧制御した直流電圧に重畳して印加すると
ともに、その定電流回路１４では、電流検知手段１７に
より検知された電流の周波数成分に基づいて、ノイズと
される高周波数域を除きどのような周波数成分のものに
ついても一律に応答させて電圧増幅率制御することとし
ているから、特にハーフトーン画像を出力する際には、
接触帯電ローラ４の凹み４ａによって、その出力画像に
接触帯電ローラ４の回転ピッチで濃度むらが顕著に生じ
るという問題があった。According to the conventional contact charging device 1 described above, the contact charging roller 4, which is in pressure contact with the image carrier 3 with a nip having a width w, is made of an elastic material. When the apparatus is stopped for a long period of time, as shown in FIG.
Since the image carrier is kept in pressure contact with the contact charging roller 4, the depression 4 a due to the nip still remains in a part of the image carrier after the image forming apparatus 2 is driven.
Is charged by the contact charging roller 4 having the dent 4a. The bias applying means 13 applies a constant-current controlled AC voltage superimposed on the constant-voltage controlled DC voltage, and the constant current circuit 14 Based on the frequency component of the current detected by the current detection means 17, the voltage amplification rate is controlled by uniformly responding to any frequency component except for a high frequency range which is regarded as noise. When outputting a halftone image,
Due to the depression 4a of the contact charging roller 4, there is a problem that density unevenness is remarkably generated in the output image at the rotation pitch of the contact charging roller 4.
【００１３】このハーフトーン画像の濃度むらは、凹み
４ａによる接触帯電ローラ４のインピーダンスの変化、
および定電流回路１４のフィードバック制御による応答
のおくれ等により、接触帯電ローラ４に印加するバイア
スが接触帯電ローラ４の周期で変動してしまうために、
接触帯電ローラ４の凹み４ａに接触する部分が、凹み４
ａ以外の部分と同様に帯電しないためと考えられる。The density unevenness of the halftone image is caused by a change in impedance of the contact charging roller 4 due to the depression 4a,
And the bias applied to the contact charging roller 4 fluctuates in the cycle of the contact charging roller 4 due to a response delay due to feedback control of the constant current circuit 14, and the like.
The portion of the contact charging roller 4 that contacts the recess 4a is
This is considered to be due to the fact that it is not charged similarly to the portions other than a.
【００１４】この発明は上述した事情に鑑み、接触帯電
ローラの変形によって発生する画像の濃度むらを可及的
に防止し画像品質を高める画像形成装置の接触帯電装置
を提供することを目的とする。SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, an object of the present invention is to provide a contact charging device of an image forming apparatus for preventing image density unevenness caused by deformation of a contact charging roller as much as possible and improving image quality. .
【００１５】[0015]
【課題を解決するための手段】上述した課題を解決する
ため、この発明では、速度Ｖｃで回転し像担持体に幅ｗ
のニップで圧接する接触帯電ローラと、該接触帯電ロー
ラに定電流回路により定電流制御した交流電圧と定電圧
回路により定電圧制御した直流電圧とを重畳して印加す
るバイアス印加手段とを具えた画像形成装置の接触帯電
装置において、前記定電流回路に、所定の周波数成分若
しくは該所定の周波数以上の周波数成分を減衰させる周
波数フィルタを具え、前記所定の周波数を、Ｖｃ／ｗ以
下に設定するようにしている。In order to solve the above-mentioned problems, according to the present invention, the image carrier is rotated at a speed Vc and has a width w.
And a bias applying means for applying an AC voltage controlled by a constant current circuit and a DC voltage controlled by a constant voltage circuit to the contact charging roller in a superimposed manner. In the contact charging device of the image forming apparatus, the constant current circuit includes a frequency filter that attenuates a predetermined frequency component or a frequency component equal to or higher than the predetermined frequency, and sets the predetermined frequency to Vc / w or lower. I have to.
【００１６】[0016]
【発明の実施の形態】以下、この発明に係わる画像形成
装置の接触帯電装置について詳述する。DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a contact charging device of an image forming apparatus according to the present invention will be described in detail.
【００１７】この発明の第１の実施例の接触帯電装置２
１は、図１で示すように、プロセススピードＶｐで回転
する前記像担持体３と、像担持体３に圧接する接触帯電
ローラ４と、該接触帯電ローラ４を定電流制御した交流
電圧と定電圧制御した直流電圧とを重畳して印加するバ
イアス印加手段２３を具えている。なお、図１は、この
発明に係わる接触帯電装置の構成を示す概念構成図で、
図８と同一部分を同一符号で示している。The contact charging device 2 according to the first embodiment of the present invention
As shown in FIG. 1, reference numeral 1 denotes the image carrier 3 rotating at a process speed Vp, a contact charging roller 4 pressed against the image carrier 3, and an AC voltage obtained by controlling the contact charging roller 4 with a constant current. There is provided a bias applying means 23 for superimposing and applying a voltage-controlled DC voltage. FIG. 1 is a conceptual configuration diagram showing a configuration of a contact charging device according to the present invention.
8 are denoted by the same reference numerals.
【００１８】このうち、前記接触帯電ローラ４は、従来
同様（図９）、幅ｗのニップで像担持体３に圧接する。The contact charging roller 4 is in pressure contact with the image carrier 3 with a nip having a width w as in the conventional case (FIG. 9).
【００１９】また、バイアス印加手段２３は、図１で示
すように、交流電圧を定電流制御する定電流回路２４
と、直流電圧を定電圧制御する定電圧回路１８と、定電
流回路２４により制御された交流電圧と定電圧回路１８
に制御された直流電圧とを重畳して印加する重畳し、接
触帯電ローラ４に印加する重畳印加手段１９とから構成
されている。As shown in FIG. 1, the bias applying means 23 includes a constant current circuit 24 for controlling the AC voltage with a constant current.
A constant voltage circuit 18 for controlling a DC voltage with a constant voltage; and an AC voltage and a constant voltage circuit 18 controlled by a constant current circuit 24.
And superimposing means 19 for superimposing and applying the controlled DC voltage to the contact charging roller 4.
【００２０】また、このうちの定電流回路２４は、交流
電圧を発生する正弦波発生手段１５と、正弦波発生手段
１５により発生した交流電圧を増幅し、重畳印加手段１
９に送出する電圧増幅手段２６と、重畳印加手段１９に
よる印加により像担持体３に流れる電流を検知する電流
検知手段１７と、該電流検知手段１７により検知された
電流の周波数成分のうち、所定の周波数以上の周波数成
分を減衰させる周波数フィルタ２７とを具え、電圧増幅
手段２６では周波数フィルタ２７を通過した周波数成分
に基づき電圧増幅率を変更して交流電圧を増幅する。The constant current circuit 24 includes a sine wave generating means 15 for generating an AC voltage and an amplifying AC voltage generated by the sine wave generating means 15.
9, a voltage amplifying means 26 for transmitting the current to the image carrier 9, a current detecting means 17 for detecting a current flowing through the image carrier 3 by application by the superimposing means 19, and a predetermined frequency component of the current detected by the current detecting means 17. And a frequency filter 27 for attenuating a frequency component equal to or higher than the frequency a.
【００２１】また、このうちの周波数フィルタ２７は、
所定の周波数（以下、減衰周波数という）Ｖｃ／ｗ以下
のものは減衰させないように設定している。The frequency filter 27 among them is
A frequency below a predetermined frequency (hereinafter, referred to as an attenuation frequency) Vc / w is set so as not to be attenuated.
【００２２】ここで、Ｖｃは接触帯電ローラ４の回転速
度である。Here, Vc is the rotation speed of the contact charging roller 4.
【００２３】本実施例では、接触帯電ローラ４は像担持
体３につれ回りしているので、接触帯電ローラ４が回転
する速度Ｖｃは、プロセススピードＶｐと一致し、Ｖｃ
＝Ｖｐである。しかし、この発明の接触帯電装置では、
接触帯電ローラ４が回転する速度Ｖｃは必ずしもプロセ
ススピードＶｐと同一でなくてもよい。In this embodiment, since the contact charging roller 4 is suspended around the image carrier 3, the speed Vc at which the contact charging roller 4 rotates is equal to the process speed Vp.
= Vp. However, in the contact charging device of the present invention,
The speed Vc at which the contact charging roller 4 rotates does not necessarily have to be the same as the process speed Vp.
【００２４】なお、この第１の実施例の接触帯電装置２
１を具えた画像形成装置２２では、従来同様、接触帯電
装置２１により一様に帯電された像担持体３の表面３ａ
に、露光手段５により画像を露光して静電潜像を形成
し、さらに該静電潜像を現像手段６により現像してトナ
ー像を形成し、該トナー像を転写手段７によって転写材
８に転写し、これにより転写材８に画像を出力する。The contact charging device 2 of the first embodiment
1, the surface 3a of the image carrier 3 uniformly charged by the contact charging device 21 as in the related art.
Then, an image is exposed by an exposure unit 5 to form an electrostatic latent image, and the electrostatic latent image is further developed by a developing unit 6 to form a toner image, and the toner image is transferred to a transfer material 8 by a transfer unit 7. The image is output to the transfer material 8.
【００２５】この第１の実施例の接触帯電装置２１で
は、定電流回路２４に、電流検知手段１７により検知さ
れた電流の周波数成分のうち減衰周波数以上の周波数成
分を減衰させる周波数フィルタ２７を具えるとともに、
この減衰周波数をＶｃ／ｗ以下に設定し、さらに、電圧
増幅手段ではこの周波数フィルタ２７を通過した周波数
成分に基づき電圧増幅率を変更して交流電圧を増幅する
ようにしたから、電圧増幅率制御において、周波数とゲ
インの関係を示す図２のように、電流検知手段１７によ
り検知された周波数成分のうち、減衰周波数以下の周波
数成分については従来のように応答し、減衰周波数以上
の周波数成分については応答をなまらるようにし、これ
により、ニップによる凹み４ａが形成されている場合に
は従来に比し凹み４ａによる変化に緩やかに応答して電
圧増幅率を変更するようにした。In the contact charging device 21 of the first embodiment, the constant current circuit 24 includes a frequency filter 27 for attenuating a frequency component equal to or higher than the attenuation frequency among the frequency components of the current detected by the current detecting means 17. As well as
This attenuation frequency is set to Vc / w or less, and the voltage amplifying means changes the voltage gain based on the frequency component passed through the frequency filter 27 to amplify the AC voltage. As shown in FIG. 2 showing the relationship between the frequency and the gain, of the frequency components detected by the current detecting means 17, a frequency component equal to or lower than the attenuation frequency responds in a conventional manner, and a frequency component equal to or higher than the attenuation frequency. Is designed to smooth the response, so that when the dent 4a is formed by the nip, the voltage amplification factor is changed more gently in response to the change due to the dent 4a than in the prior art.
【００２６】このようにすると、画像形成装置２２を長
時間停止後に駆動させた際、ニップによる凹み４ａが残
った接触帯電ローラ４により像担持体３を帯電する場合
であっても、ハーフトーン画像を出力する際に、その出
力画像に接触帯電ローラ４の回転ピッチ４で、濃度むら
が生じることを可及的に防止することができた。With this arrangement, when the image forming apparatus 22 is driven after being stopped for a long time, even if the image carrier 3 is charged by the contact charging roller 4 in which the dent 4a due to the nip remains, the halftone image can be formed. When the image was output, it was possible to prevent the occurrence of density unevenness in the output image at the rotation pitch 4 of the contact charging roller 4 as much as possible.
【００２７】また、この第１の実施例の接触帯電装置２
１では、周波数フィルタ２７は、減衰周波数Ｖｃ／ｗ以
上の周波数成分を減衰することとしたが、この発明の周
波数フィルタはこれに限定せず、周波数フィルタ２７は
減衰周波数Ｖｃ／ｗの周波数成分のみを減衰するもので
あってもよい。Further, the contact charging device 2 of the first embodiment
In 1, the frequency filter 27 attenuates the frequency component equal to or higher than the attenuation frequency Vc / w. However, the frequency filter of the present invention is not limited to this, and the frequency filter 27 has only the frequency component of the attenuation frequency Vc / w. May be attenuated.
【００２８】また、この第１の実施例の接触帯電装置２
１では、上述のように、その定電流回路２４に周波数フ
ィルタ２７を具えることとしたが、この発明の接触帯電
装置は、定電流回路２４の構成に、図１と同一部分を同
一符号で示す図３のように、さらに上述した減衰周波数
を変更する減衰周波数変更手段３８を具えた定電流回路
３４から構成されていてもよい。Further, the contact charging device 2 of the first embodiment
1, as described above, the constant current circuit 24 is provided with the frequency filter 27. However, the contact charging device of the present invention has the same reference numerals in FIG. As shown in FIG. 3, the constant current circuit 34 may further include a constant current circuit 34 having an attenuation frequency changing unit 38 for changing the above-described attenuation frequency.
【００２９】次に、減衰周波数変更手段を具えた接触帯
電装置について、第２の実施例の接触帯電装置４１、第
３の実施例の接触帯電装置５１、第４の実施例の接触帯
電装置６１、第５の実施例の接触帯電装置７１で説明す
る。Next, regarding the contact charging device provided with the attenuation frequency changing means, the contact charging device 41 of the second embodiment, the contact charging device 51 of the third embodiment, and the contact charging device 61 of the fourth embodiment. The contact charging device 71 of the fifth embodiment will be described.
【００３０】第２の実施例の接触帯電装置４１は、図１
と同一部分を同一符号で示す図４のように、周波数フィ
ルタ２７を具えた定電流回路４３に、プロセススピード
Ｖｐの切り替えに応じて、周波数フィルタ２７の減衰周
波数を切り替える減衰周波数変更手段４８を具えてい
る。The contact charging device 41 of the second embodiment is similar to that of FIG.
As shown in FIG. 4 in which the same parts as in FIG. 4 are denoted by the same reference numerals, a constant current circuit 43 having a frequency filter 27 is provided with an attenuation frequency changing means 48 for switching the attenuation frequency of the frequency filter 27 in accordance with the switching of the process speed Vp. I have.
【００３１】本実施例でも、接触帯電ローラ４は像担持
体３とつれ回りするので、接触帯電ローラ４の回転速度
ＶｃがプロセススピードＶｐと一致し、Ｖｃ＝Ｖｐであ
ることとして説明する。Also in the present embodiment, since the contact charging roller 4 rotates with the image carrier 3, the description will be made on the assumption that the rotation speed Vc of the contact charging roller 4 matches the process speed Vp, and Vc = Vp.
【００３２】この減衰周波数変更手段４８は、像担持体
３を回転駆動するモータのプロセススピードＶｐを切り
替えるプロセススピード切替手段４９によって、プロセ
ススピードＶｐが通常の速度から低い速度に切り替えら
れた際、減衰周波数を低く設定する。The attenuation frequency changing means 48 attenuates when the process speed Vp is switched from the normal speed to a low speed by the process speed switching means 49 for switching the process speed Vp of the motor for rotating and driving the image carrier 3. Set the frequency lower.
【００３３】近年、画像形成装置の高解像度が進んでい
るが、レーザ露光装置のポリゴンミラーの回転数や画像
信号の周波数の制限等により、高解像度時にはプロセス
スピードＶｐを低下させることにより高解像度を実現す
ることが公知技術として提案されているが、この第２の
実施例の接触帯電装置４１では、プロセススピード切替
手段４９によってプロセススピードＶｐが通常の速度か
ら低い速度に切り替えられた際には、周波数フィルタ２
７の減衰周波数を減衰周波数変更手段４８によって低く
変化させるので、ハーフトーン画像での接触帯電ローラ
４の凹み４ａによる濃度むらを抑えることのできる減衰
周波数を設定でき、プロセススピードＶｐが通常の速度
に切り替えられた際には周波数フィルタ２７の減衰周波
数を減衰周波数変更手段４８によって高く変化させるの
で過大に定電流制御の反応を遅くすることがないため、
定電流制御の反応が遅すぎて接触帯電ローラ４の抵抗む
らに対応しきれずに帯電むらが生じる虞を防止すること
ができる。In recent years, the high resolution of the image forming apparatus has been advanced. However, due to the limitation of the rotation speed of the polygon mirror of the laser exposure apparatus, the frequency of the image signal, and the like, the high resolution is reduced by lowering the process speed Vp at the high resolution. Although it is proposed as a known technique to realize this, in the contact charging device 41 of the second embodiment, when the process speed Vp is switched from the normal speed to a low speed by the process speed switching means 49, Frequency filter 2
7, the attenuation frequency can be set low by the attenuation frequency changing means 48, so that an attenuation frequency that can suppress density unevenness due to the recess 4a of the contact charging roller 4 in a halftone image can be set, and the process speed Vp becomes a normal speed. When switched, the attenuation frequency of the frequency filter 27 is increased by the attenuation frequency changing means 48, so that the response of the constant current control is not excessively delayed.
It is possible to prevent the possibility that the unevenness of the charging occurs because the reaction of the constant current control is too slow to cope with the unevenness of the resistance of the contact charging roller 4.
【００３４】また、第２の実施例の接触帯電装置４１で
は、減衰周波数変更手段４８は、プロセススピード切替
手段４９によりプロセススピードＶｐが通常の速度から
低い速度に切り替えられた際、周波数フィルタ２７の減
衰周波数を低く設定することとしたが、減衰周波数変更
手段４８はこれに限定せず、プロセススピードＶｐに基
づいて減衰周波数を変更するものであればよく、例え
ば、減衰周波数変更手段は、プロセススピードＶｐの変
化の大きさに応じて減衰周波数を変更するものであって
もよい。Further, in the contact charging device 41 of the second embodiment, when the process speed switching means 49 switches the process speed Vp from a normal speed to a low speed, the attenuation frequency changing means 48 controls the frequency filter 27. Although the attenuation frequency is set to be low, the attenuation frequency changing means 48 is not limited to this, and may be any means that changes the attenuation frequency based on the process speed Vp. The attenuation frequency may be changed according to the magnitude of the change in Vp.
【００３５】また、本実施例では、接触帯電ローラ４の
回転速度ＶｃとプロセススピードＶｐとが、Ｖｃ＝Ｖｐ
であることとして説明したが、接触帯電ローラ４の回転
速度Ｖｃと、プロセススピードＶｐが異なる場合には、
接触帯電ローラ４の回転速度Ｖｃの変化に応じて減衰周
波数を変更してもよい。In this embodiment, the rotational speed Vc of the contact charging roller 4 and the process speed Vp are calculated as follows: Vc = Vp
However, when the rotation speed Vc of the contact charging roller 4 is different from the process speed Vp,
The attenuation frequency may be changed according to the change in the rotation speed Vc of the contact charging roller 4.
【００３６】また、第２の実施例の接触帯電装置４１で
は、減衰周波数変更手段４８はプロセススピードＶｐに
基づいて減衰周波数を変更するものとしたが、減衰周波
数変更手段４８はこれに限定せず、ニップ幅ｗの変化の
大きさに応じて減衰周波数を変更するものでもよい。In the contact charging device 41 of the second embodiment, the attenuation frequency changing means 48 changes the attenuation frequency based on the process speed Vp. However, the attenuation frequency changing means 48 is not limited to this. Alternatively, the attenuation frequency may be changed according to the magnitude of the change in the nip width w.
【００３７】次に、ニップ幅ｗの変化の大きさに応じて
周波数フィルタの減衰周波数を変更する第３の実施例の
接触帯電装置について説明する。Next, a description will be given of a contact charging device according to a third embodiment in which the attenuation frequency of the frequency filter is changed in accordance with the magnitude of the change in the nip width w.
【００３８】この第３の実施例の接触帯電装置５１は、
図１と同一部分を同一符号で示す図５のように、周波数
フィルタ２７を具えた定電流回路５４に、ニップ幅ｗの
変化が大きい場合に周波数フィルタ２７の減衰周波数を
切り替える減衰周波数変更手段５８を具えている。The contact charging device 51 according to the third embodiment comprises:
As shown in FIG. 5 in which the same parts as those in FIG. 1 are denoted by the same reference numerals, a constant current circuit 54 having a frequency filter 27 is provided with an attenuation frequency changing means 58 for switching the attenuation frequency of the frequency filter 27 when the change in the nip width w is large. It has.
【００３９】この減衰周波数変更手段５８は、接触帯電
ローラ４および像担持体３を内部に具え、画像形成装置
５２に着脱自在に装着されるプロセスカートリッジが交
換されたことをプロセスカートリッジ交換検出手段５９
によって検出した際、接触帯電ローラ４を所定回転させ
た後、減衰周波数を高く設定する。The attenuation frequency changing means 58 includes the contact charging roller 4 and the image carrier 3 therein, and detects that the process cartridge detachably mounted on the image forming apparatus 52 has been replaced.
When the contact charging roller 4 is rotated by a predetermined amount, the attenuation frequency is set high.
【００４０】第３の実施例の接触帯電装置５１による
と、プロセスカートリッジが交換されたことを検出した
際、減衰周波数変更手段５８によって減衰周波数を高く
設定するので、定電流制御の反応が遅すぎて接触帯電ロ
ーラ４の抵抗むらに対応しきれずに帯電むらが生じてし
まう虞を、更に可及的に防止することができた。According to the contact charging device 51 of the third embodiment, when the replacement of the process cartridge is detected, the attenuation frequency is set high by the attenuation frequency changing means 58, so that the response of the constant current control is too slow. As a result, it is possible to further prevent as much as possible the possibility that the charging unevenness is generated without being able to cope with the resistance unevenness of the contact charging roller 4.
【００４１】なお、第３の実施例の接触帯電装置５１で
ハーフトーン画像を出力する際、その出力画像に接触帯
電ローラ４の回転ピッチで濃度むらが生じることは可及
的に防止されたことは言うまでもない。When a halftone image is output by the contact charging device 51 of the third embodiment, unevenness in the output image due to the rotation pitch of the contact charging roller 4 is prevented as much as possible. Needless to say.
【００４２】なお、この第３の実施例の接触帯電装置５
１では、プロセスカートリッジの交換後の接触帯電ロー
ラ４は短時間で凹みを回復することが比較的容易である
ため、プロセスカートリッジが交換されたことを検出し
た際、接触帯電ローラ４を所定回転させた後に、周波数
フィルタ２７の減衰周波数を切り替えるようにタイミン
グ制御している。The contact charging device 5 of the third embodiment
In No. 1, since it is relatively easy to recover the dent in a short time after the replacement of the process cartridge, the contact charging roller 4 is rotated by a predetermined amount when the replacement of the process cartridge is detected. After that, the timing is controlled so that the attenuation frequency of the frequency filter 27 is switched.
【００４３】また、第３の実施例の接触帯電装置５１で
は、周波数変更手段５８はプロセスカートリッジが交換
された際、周波数フィルタ２７の減衰周波数を高く設定
するものとしたが、減衰周波数変更手段５８はこれに限
定せず、ニップ幅ｗの変化の大きさに応じて周波数フィ
ルタ２７の減衰周波数を変更するものであればよく、た
とえば、画像形成装置の停止時間に応じて、減衰周波数
を変更するものであってもよい。In the contact charging device 51 of the third embodiment, the frequency changing means 58 sets the attenuation frequency of the frequency filter 27 high when the process cartridge is replaced. The present invention is not limited to this, but may be any as long as the attenuation frequency of the frequency filter 27 is changed according to the magnitude of the change in the nip width w. For example, the attenuation frequency is changed according to the stop time of the image forming apparatus. It may be something.
【００４４】次に、ニップ幅ｗの変化の大きさに応じて
減衰周波数を変更する接触帯電装置の別の実施例とし
て、画像形成装置の停止時間に応じて、減衰周波数を変
更する第４の実施例の接触帯電装置について説明する。Next, as another embodiment of the contact charging device for changing the attenuation frequency in accordance with the magnitude of the change in the nip width w, a fourth embodiment in which the attenuation frequency is changed in accordance with the stop time of the image forming apparatus. The contact charging device of the embodiment will be described.
【００４５】第４の実施例の接触帯電装置６１は、図１
と同一部分を同一符号で示す図６のように、周波数フィ
ルタ２７を具えた定電流回路６４に、画像形成装置６２
が所定時間以上停止した際、周波数フィルタ２７の減衰
周波数を切り替える減衰周波数変更手段６８を具えてい
る。The contact charging device 61 of the fourth embodiment is similar to that of FIG.
As shown in FIG. 6 in which the same parts as those in FIG.
Is provided with an attenuation frequency changing means 68 for switching the attenuation frequency of the frequency filter 27 when stopped for a predetermined time or more.
【００４６】この周波数変更手段６８は、像担持体３を
回転駆動するモータの停止状態を検出するタイマー６９
によって画像形成装置６２が所定時間以上停止したこと
を検出した際、減衰周波数を高く設定する。The frequency changing means 68 is provided with a timer 69 for detecting the stop state of the motor for driving the image carrier 3 to rotate.
When the image forming apparatus 62 detects that the image forming apparatus 62 has stopped for a predetermined time or more, the attenuation frequency is set high.
【００４７】この第４の実施例の接触帯電装置６１によ
ると、タイマー６９により画像形成装置６２が所定時間
以上停止したことを検出した際、減衰周波数変更手段６
８によって減衰周波数を高く設定するので、ニップ幅ｗ
の変化が大きい場合でも定電流制御の反応が遅すぎて接
触帯電ローラの抵抗むらに対応しきれず、帯電むらが生
じてしまう虞を、さらに可及的に防止することができ
た。According to the contact charging device 61 of the fourth embodiment, when the timer 69 detects that the image forming device 62 has stopped for a predetermined time or more, the attenuation frequency changing means 6
8, the attenuation frequency is set high, so that the nip width w
Even when the change in the constant current control is large, the possibility that the response of the constant current control is too slow to cope with the non-uniform resistance of the contact charging roller and the non-uniform charging occurs can be prevented as much as possible.
【００４８】なお、第４の実施例の接触帯電装置６１で
ハーフトーン画像を出力する際、その出力画像に接触帯
電ローラ４の回転ピッチで、濃度むらが生じることを可
及的に防止することができたことは言うまでもない。When a halftone image is output by the contact charging device 61 of the fourth embodiment, it is possible to prevent density unevenness from occurring in the output image due to the rotation pitch of the contact charging roller 4 as much as possible. Needless to say, we did.
【００４９】なお、この第４の実施例の接触帯電装置６
１では、画像形成装置６２の停止時間をタイマー６９で
検出するとともに、停止時間が所定以上であることが検
出された場合、周波数フィルタ２７の減衰周波数を高く
設定することとしたが、これに限定せず、像担持体３を
駆動するモータの回転数をカウンタで検出し該回転数か
ら接触帯電装置６１の経時的変化を考慮し、減衰周波数
を変更するようにしてもよいし、また、タイマー６９ま
たはカウンタを使用して接触帯電装置６１の停止時間お
よびその経時的変化に基づいて、減衰周波数を変更する
ようにしてもよい。The contact charging device 6 of the fourth embodiment
In No. 1, the stop time of the image forming apparatus 62 is detected by the timer 69, and when it is detected that the stop time is equal to or longer than a predetermined time, the attenuation frequency of the frequency filter 27 is set to be high. Instead, the number of rotations of the motor for driving the image carrier 3 may be detected by a counter, and the decay frequency may be changed based on the number of rotations in consideration of the change over time of the contact charging device 61. The damping frequency may be changed based on the stop time of the contact charging device 61 and its temporal change using a counter 69 or a counter.
【００５０】次に、ニップ幅ｗの変化の大きさに応じて
減衰周波数を変更する接触帯電装置のさらに別の実施例
として、接触帯電ローラ４の種類に応じて減衰周波数を
変更する第５の実施例の接触帯電装置について説明す
る。Next, as still another embodiment of the contact charging device for changing the attenuation frequency in accordance with the magnitude of the change in the nip width w, a fifth embodiment in which the attenuation frequency is changed in accordance with the type of the contact charging roller 4 will be described. The contact charging device of the embodiment will be described.
【００５１】また、この第５の実施例の接触帯電装置７
１は、図１と同一部分を同一符号で示す図７のように、
周波数フィルタ２７を具えた定電流回路７４に、プロセ
スカートリッジ内の接触帯電ローラ４の種類を接触帯電
ローラ種類判別手段７９によって判別するとともに、判
別された接触帯電ローラ４の材質、径等に応じて、減衰
周波数を変更する周波数変更手段７８を具えている。Further, the contact charging device 7 of the fifth embodiment
1 is the same as FIG. 1 with the same reference numerals as in FIG.
In the constant current circuit 74 having the frequency filter 27, the type of the contact charging roller 4 in the process cartridge is discriminated by the contact charging roller type discriminating means 79, and according to the discriminated material and diameter of the contact charging roller 4. , Frequency changing means 78 for changing the attenuation frequency.
【００５２】第５の実施例の接触帯電装置７１による
と、プロセスカートリッジを交換した際、プロセスカー
トリッジ毎に記憶された内部に配設された接触帯電ロー
ラ４の種類を接触帯電ローラ種類判別手段７９によって
判別し、判別された接触帯電ローラ４の種類に応じて減
衰周波数を変更するので、ニップ幅ｗの変化が大きい場
合でも定電流制御の反応が遅すぎて接触帯電ローラ４の
抵抗むらに対応しきれずに帯電むらが生じてしまう虞
を、さらに可及的に防止することができた。According to the contact charging device 71 of the fifth embodiment, when the process cartridges are replaced, the type of the contact charging roller 4 stored inside each process cartridge is determined by the contact charging roller type determining means 79. And the attenuation frequency is changed in accordance with the determined type of the contact charging roller 4. Therefore, even when the nip width w is largely changed, the response of the constant current control is too slow to cope with the uneven resistance of the contact charging roller 4. It was possible to further prevent the possibility of uneven charging due to failure.
【００５３】なお、第５の実施例の接触帯電装置７１で
ハーフトーン画像を出力する際、その出力画像に接触帯
電ローラ４の回転ピッチで濃度むらが生じることを可及
的に防止することができたことは言うまでもない。When a halftone image is output by the contact charging device 71 of the fifth embodiment, it is possible to minimize the occurrence of density unevenness in the output image due to the rotation pitch of the contact charging roller 4. Needless to say, we did.
【００５４】また、第３の実施例の接触帯電装置５１、
第４の実施例の接触帯電装置６１、第５の実施例の接触
帯電装置７１では、減衰周波数変更手段は、それぞれプ
ロセスカートリッジの交換、画像形成装置の停止時間、
接触帯電ローラ４の種類に応じ、減衰周波数を変更する
こととしたが、減衰周波数変更手段はこれに限定され
ず、減衰周波数変更手段はニップ幅ｗに基づいて減衰周
波数を変更するものであればよい。The contact charging device 51 of the third embodiment,
In the contact charging device 61 according to the fourth embodiment and the contact charging device 71 according to the fifth embodiment, the attenuation frequency changing means includes replacement of the process cartridge, stoppage time of the image forming apparatus,
The damping frequency is changed according to the type of the contact charging roller 4, but the damping frequency changing means is not limited to this. The damping frequency changing means may change the damping frequency based on the nip width w. Good.
【００５５】[0055]
【発明の効果】以上説明したように、この発明では、速
度Ｖｃで回転し像担持体に幅ｗのニップで圧接する接触
帯電ローラと、該接触帯電ローラに定電流回路により定
電流制御した交流電圧と定電圧回路により定電圧制御し
た直流電圧とを重畳して印加するバイアス印加手段とを
具えた画像形成装置の接触帯電装置において、前記定電
流回路に、所定の周波数成分若しくは該所定の周波数以
上の周波数成分を減衰する周波数フィルタを具え、前記
所定の周波数を、Ｖｃ／ｗ以下に設定することとしたか
ら、画像形成装置を長時間停止後に駆動させた際ニップ
による凹みが残った接触帯電ローラにより像担持体を帯
電する場合であっても、通常の画像を出力する際、その
出力画像に帯電むらを生じることを可及的に防止するこ
とができるとともに、ハーフトーン画像を出力する際に
も、その出力画像に接触帯電ローラの回転ピッチで濃度
むらが生じることを可及的に防止することができる。As described above, according to the present invention, the contact charging roller which rotates at the speed Vc and presses against the image carrier with the nip having the width w, and the alternating current which is controlled by the constant current circuit to the contact charging roller. In a contact charging device of an image forming apparatus, comprising: a bias application unit for applying a voltage and a DC voltage controlled by a constant voltage circuit in a superimposed manner, the constant current circuit includes a predetermined frequency component or the predetermined frequency. A frequency filter for attenuating the above-mentioned frequency components is provided, and the predetermined frequency is set at Vc / w or less. Even when the image carrier is charged by the roller, it is possible to prevent as much as possible the occurrence of uneven charging in the output image when outputting a normal image. Even when outputting the halftone image, it is possible to prevent the density unevenness in the rotation pitch of the contact charging roller to the output image is generated as much as possible.
【００５６】したがって、この発明の接触帯電装置によ
ると、接触帯電ローラの変形によって発生する濃度むら
を可及的に防止し、画像品質の高い画像形成装置を提供
することができる。Therefore, according to the contact charging device of the present invention, density unevenness caused by deformation of the contact charging roller can be prevented as much as possible, and an image forming apparatus with high image quality can be provided.
【図１】図１は、この発明の第１の実施例の接触帯電装
置の構成を示す概念構成図。FIG. 1 is a conceptual configuration diagram showing a configuration of a contact charging device according to a first embodiment of the present invention.
【図２】図２は、この発明の接触帯電装置の定電流回路
を構成する電圧増幅手段の周波数特性を示す図。FIG. 2 is a diagram showing frequency characteristics of a voltage amplifying unit constituting a constant current circuit of the contact charging device of the present invention.
【図３】図３は、この発明の接触帯電装置であって、減
衰周波数変更手段を具えた接触帯電装置の構成を示す概
念構成図。FIG. 3 is a conceptual configuration diagram showing a configuration of a contact charging device according to the present invention, which is provided with an attenuation frequency changing unit.
【図４】図４は、この発明の第２の実施例の接触帯電装
置の構成を示す概念構成図。FIG. 4 is a conceptual configuration diagram showing a configuration of a contact charging device according to a second embodiment of the present invention.
【図５】図５は、この発明の第３の実施例の接触帯電装
置の構成を示す概念構成図。FIG. 5 is a conceptual configuration diagram showing a configuration of a contact charging device according to a third embodiment of the present invention.
【図６】図６は、この発明の第４の実施例の接触帯電装
置の構成を示す概念構成図。FIG. 6 is a conceptual configuration diagram showing a configuration of a contact charging device according to a fourth embodiment of the present invention.
【図７】図７は、この発明の第５の実施例の接触帯電装
置の構成を示す概念構成図。FIG. 7 is a conceptual configuration diagram showing a configuration of a contact charging device according to a fifth embodiment of the present invention.
【図８】図８は、従来の接触帯電装置の構成を示す概念
構成図。FIG. 8 is a conceptual configuration diagram showing a configuration of a conventional contact charging device.
【図９】図９は、従来の接触帯電装置の要部拡大断面
図。FIG. 9 is an enlarged sectional view of a main part of a conventional contact charging device.
【図１０】図１０は、従来の接触帯電装置の定電流回路
を構成する電圧増幅手段の周波数特性を示す図。FIG. 10 is a diagram showing frequency characteristics of a voltage amplifying unit constituting a constant current circuit of a conventional contact charging device.
【図１１】図１１は、従来の接触帯電装置の要部拡大断
面図。FIG. 11 is an enlarged sectional view of a main part of a conventional contact charging device.
３…像担持体 ４…接触帯電ローラ １８…定電流回路 ２１、３１、４１、５１、６１、７１…接触帯電装置 ２２、３２、４２、５２、６２、７２…画像形成装置 ２３、３３、４３、５３、６３、７３…バイアス印加手
段 ２４、３４、４４、５４、６４、７４…定電流回路 ２７…周波数フィルタ ３８、４８、５８、６８、７８…減衰周波数変更手段DESCRIPTION OF SYMBOLS 3 ... Image carrier 4 ... Contact charging roller 18 ... Constant current circuit 21, 31, 41, 51, 61, 71 ... Contact charging device 22, 32, 42, 52, 62, 72 ... Image forming device 23, 33, 43 , 53, 63, 73 ... bias applying means 24, 34, 44, 54, 64, 74 ... constant current circuit 27 ... frequency filter 38, 48, 58, 68, 78 ... attenuation frequency changing means
───────────────────────────────────────────────────── フロントページの続き (72)発明者 岡田 敦 埼玉県岩槻市府内３丁目７番１号 富士ゼ ロックス株式会社岩槻事業所内 Ｆターム(参考） 2H003 BB11 CC05 DD03 EE11 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Atsushi Okada 3-7-1, Fuuchi, Iwatsuki-shi, Saitama F-term in Fuji Xerox Co., Ltd. Iwatsuki Office 2H003 BB11 CC05 DD03 EE11
Claims (6)
プで圧接する接触帯電ローラと、 該接触帯電ローラに定電流回路により定電流制御した交
流電圧と定電圧回路により定電圧制御した直流電圧とを
重畳して印加するバイアス印加手段とを具えた画像形成
装置の接触帯電装置において、 前記定電流回路に、所定の周波数成分若しくは該所定の
周波数以上の周波数成分を減衰させる周波数フィルタを
具え、 前記所定の周波数を、Ｖｃ／ｗ以下に設定したことを特
徴とする画像形成装置の接触帯電装置。1. A contact charging roller which rotates at a speed Vc and presses against an image carrier with a nip having a width w, and an AC voltage and a constant voltage controlled by a constant current circuit and a constant voltage circuit to the contact charging roller. And a bias applying means for applying a superposed DC voltage to the constant current circuit, wherein the constant current circuit attenuates a predetermined frequency component or a frequency component equal to or higher than the predetermined frequency. A contact charging device for an image forming apparatus, wherein the predetermined frequency is set to Vc / w or less.
周波数フィルタの前記所定の周波数を変更する減衰周波
数変更手段を具えるようにしたことを特徴とする請求項
（１）記載の画像形成装置の接触帯電装置。2. The image forming apparatus according to claim 1, wherein the contact charging device of the image forming apparatus includes an attenuation frequency changing unit that changes the predetermined frequency of the frequency filter. Device contact charging device.
に基づき前記所定の周波数を変更するようにしたことを
特徴とする請求項（２）記載の画像形成装置の接触帯電
装置。3. The method according to claim 2, wherein said attenuation frequency changing means is configured to control said speed Vc.
3. The contact charging device of an image forming apparatus according to claim 2, wherein the predetermined frequency is changed based on the following.
像形成装置に着脱自在なプロセスカートリッジ内に配設
され、 前記減衰周波数変更手段は、前記プロセスカートリッジ
が交換された際、前記所定の周波数を変更するようにし
たことを特徴とする請求項（２）記載の画像形成装置の
接触帯電装置。4. The image carrier and the contact charging roller are provided in a process cartridge detachable from the image forming apparatus, and the attenuation frequency changing means is configured to change the predetermined frequency when the process cartridge is replaced. 3. The contact charging device for an image forming apparatus according to claim 2, wherein the frequency is changed.
装置が所定時間停止した際、前記所定の周波数を変更す
るようにしたことを特徴とする請求項（２）記載の画像
形成装置の接触帯電装置。5. The image forming apparatus according to claim 2, wherein said attenuation frequency changing means changes said predetermined frequency when said image forming apparatus is stopped for a predetermined time. Charging device.
ローラの種類に応じて、前記所定の周波数を変更するよ
うにしたことを特徴とする請求項（２）記載の画像形成
装置の接触帯電装置。6. The contact charging apparatus according to claim 2, wherein said attenuation frequency changing means changes said predetermined frequency in accordance with a type of said contact charging roller. apparatus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01458399A JP3713992B2 (en) | 1999-01-22 | 1999-01-22 | Contact charging device for image forming apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01458399A JP3713992B2 (en) | 1999-01-22 | 1999-01-22 | Contact charging device for image forming apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000214661A true JP2000214661A (en) | 2000-08-04 |
| JP3713992B2 JP3713992B2 (en) | 2005-11-09 |
Family
ID=11865198
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01458399A Expired - Fee Related JP3713992B2 (en) | 1999-01-22 | 1999-01-22 | Contact charging device for image forming apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3713992B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7577378B2 (en) | 2006-03-30 | 2009-08-18 | Fuji Xerox Co., Ltd. | Image carrier unit and image forming apparatus |
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| JPH01267667A (en) * | 1988-04-20 | 1989-10-25 | Canon Inc | Electrostatic charging device |
| JPH04171464A (en) * | 1990-11-02 | 1992-06-18 | Canon Inc | Charging device |
| JPH05223513A (en) * | 1992-02-07 | 1993-08-31 | Canon Inc | Detecting apparatus for thickness of body to be electrified, electrifying apparatus and image forming apparatus |
| JPH05289470A (en) * | 1992-04-10 | 1993-11-05 | Brother Ind Ltd | Contact type electrostatic charge device |
| JPH08160718A (en) * | 1994-12-07 | 1996-06-21 | Canon Inc | Image forming device |
| JPH096097A (en) * | 1995-06-16 | 1997-01-10 | Canon Inc | Electrifier for image forming device |
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1999
- 1999-01-22 JP JP01458399A patent/JP3713992B2/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01267667A (en) * | 1988-04-20 | 1989-10-25 | Canon Inc | Electrostatic charging device |
| JPH04171464A (en) * | 1990-11-02 | 1992-06-18 | Canon Inc | Charging device |
| JPH05223513A (en) * | 1992-02-07 | 1993-08-31 | Canon Inc | Detecting apparatus for thickness of body to be electrified, electrifying apparatus and image forming apparatus |
| JPH05289470A (en) * | 1992-04-10 | 1993-11-05 | Brother Ind Ltd | Contact type electrostatic charge device |
| JPH08160718A (en) * | 1994-12-07 | 1996-06-21 | Canon Inc | Image forming device |
| JPH096097A (en) * | 1995-06-16 | 1997-01-10 | Canon Inc | Electrifier for image forming device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7577378B2 (en) | 2006-03-30 | 2009-08-18 | Fuji Xerox Co., Ltd. | Image carrier unit and image forming apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3713992B2 (en) | 2005-11-09 |
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