JPH01231073A - Method for controlling electrostatic charging of photosensitive body - Google Patents
Method for controlling electrostatic charging of photosensitive bodyInfo
- Publication number
- JPH01231073A JPH01231073A JP63056265A JP5626588A JPH01231073A JP H01231073 A JPH01231073 A JP H01231073A JP 63056265 A JP63056265 A JP 63056265A JP 5626588 A JP5626588 A JP 5626588A JP H01231073 A JPH01231073 A JP H01231073A
- Authority
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- Japan
- Prior art keywords
- charging
- photoreceptor
- potential
- sensor
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims description 18
- 238000007786 electrostatic charging Methods 0.000 title abstract 2
- 238000007600 charging Methods 0.000 claims abstract description 48
- 238000005259 measurement Methods 0.000 claims abstract description 6
- 108091008695 photoreceptors Proteins 0.000 claims description 61
- 238000002474 experimental method Methods 0.000 claims description 4
- 238000012937 correction Methods 0.000 abstract description 3
- 238000011161 development Methods 0.000 abstract description 2
- 238000013016 damping Methods 0.000 abstract 2
- 238000010586 diagram Methods 0.000 description 6
- 238000012546 transfer Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 4
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 description 3
- 238000004140 cleaning Methods 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 230000014759 maintenance of location Effects 0.000 description 3
- 229910052711 selenium Inorganic materials 0.000 description 3
- 239000011669 selenium Substances 0.000 description 3
- 230000003068 static effect Effects 0.000 description 2
- 235000010724 Wisteria floribunda Nutrition 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 210000001215 vagina Anatomy 0.000 description 1
Landscapes
- Control Or Security For Electrophotography (AREA)
- Electrostatic Charge, Transfer And Separation In Electrography (AREA)
Abstract
Description
【発明の詳細な説明】
「産業上の利用分野」
本発明は、感光体の表面電位減衰特性の変化に応じて帯
電器へ印加する帯電電流を制御する感光体の帯電制御方
法に関する。DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method for controlling the charging of a photoreceptor, which controls the charging current applied to a charger according to changes in the surface potential decay characteristics of the photoreceptor.
「従来の技術」
従来の例えば像担持体としてセレン系の感光体を備えた
電子写真複写機、プリンタ等においては第４図に示すよ
うに環境温度が上昇すると感光体の電位減衰係数が大き
くなるという性質を有している。感光体の電位減衰係数
が大きくなると、電荷保持能力が低下し所定の帯電量を
帯電器で与えてもすぐに表面電位が低下してしまい良好
な画像形成を行うことができなかった。"Prior Art" In conventional electrophotographic copying machines, printers, etc. that are equipped with a selenium-based photoreceptor as an image carrier, as shown in Figure 4, as the environmental temperature rises, the potential attenuation coefficient of the photoreceptor increases. It has this property. When the potential attenuation coefficient of the photoreceptor increases, its charge retention ability decreases, and even if a predetermined amount of charge is applied by a charger, the surface potential immediately decreases, making it impossible to form a good image.
そこで、このような感光体の表面電位の低下を補い、良
好な画像品質を保持するために種々の帯電電流を制御す
る帯電制御方法が提案されている。Therefore, charging control methods have been proposed in which various charging currents are controlled in order to compensate for such a decrease in the surface potential of the photoreceptor and maintain good image quality.
例えば、感光体の表面電位を１個の電位センサで測定し
た後、感光体を所定速度で少なくとも１回転させて前記
電位センサで再測定し、その測定値に基づき電位減衰率
を算出し、帯電器への帯電電流を制御する方法や、感光
体表面電位を感光体の回転力°向に所定角度ずらせて配
置した複数個電位センサで測定し、この測定値に基づき
電位減衰率を算出し、帯電器への帯電電流を制御する方
法等が知られている。For example, after measuring the surface potential of a photoconductor with one potential sensor, the photoconductor is rotated at least once at a predetermined speed and remeasured with the potential sensor, and the potential attenuation rate is calculated based on the measured value. A method of controlling the charging current to the device, measuring the surface potential of the photoreceptor with multiple potential sensors arranged at a predetermined angle in the direction of the rotational force of the photoreceptor, and calculating the potential attenuation rate based on this measurement value. 2. Description of the Related Art Methods of controlling charging current to a charger are known.
「発明が解決しようとする課題」
しかし、従来のこれらの制御方法には以下のような問題
点があった。つまり、前者では表面電位の減衰係数を測
定するために感光体を何回か回転させる時間が必要であ
り、装置の起動時間及び表面電位の減衰係数を測定する
ため待機時間を要した。そして、この待機時間内におい
てはプリントを行うことができなかった。この待機時間
は信号入力と同時に画像を形成しなければならないプリ
ンタ等にとっては致命的である。またこの制御方法では
感光体の温度が変動中であったり、感光体がグランド電
位に対して浮く等のトラブルが生じた場合、必要以上の
高電圧が印加され電源が破損するなどの問題点が存在し
た。"Problems to be Solved by the Invention" However, these conventional control methods have the following problems. That is, in the former case, it was necessary to rotate the photoreceptor several times in order to measure the attenuation coefficient of the surface potential, and it required a start-up time of the device and a standby time to measure the attenuation coefficient of the surface potential. Printing could not be performed within this waiting time. This waiting time is fatal for printers and the like that must form images at the same time as signal input. Additionally, with this control method, if a problem occurs such as the temperature of the photoreceptor fluctuating or the photoreceptor floating relative to the ground potential, a higher voltage than necessary will be applied and the power supply will be damaged. Were present.
また、後者においては電位センサが複数個必要となるた
め製造コストが高くなるという欠点が存在した。Furthermore, the latter method requires a plurality of potential sensors, which has the disadvantage of increasing manufacturing costs.
本発明の目的は上述した従来の技術の欠点に鑑みなされ
たもので、温度や湿度等の外乱に対して安定した感光体
の帯電制御を行うことのできる感光体帯電制御方法を提
供することにある。さらに本発明は帯電制御を行う際に
無用の待機時間を必要としない感光体帯電制御方法を提
供することを目的とする。SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above-mentioned drawbacks of the conventional technology, and it is an object of the present invention to provide a photoconductor charge control method that can perform stable charge control of a photoconductor against disturbances such as temperature and humidity. be. A further object of the present invention is to provide a photoreceptor charging control method that does not require unnecessary waiting time when performing charging control.
「課題を解決するための手段」
本発明に係る感光体帯電制御方法は、感光体の表面に測
定用の帯電パターンを形成し、この形成された帯電パタ
ーンを１回測定するとともに、感光体表面温度を測定し
、この測定値から求められた電位減衰係数にしたがって
帯電器への帯電電流を制御するものである。"Means for Solving the Problems" A photoreceptor charging control method according to the present invention forms a charging pattern for measurement on the surface of a photoreceptor, measures the formed charging pattern once, and measures the charging pattern on the surface of the photoreceptor. The temperature is measured and the charging current to the charger is controlled according to the potential attenuation coefficient determined from the measured value.
「実施例」
以下、本発明の一実施例について添付図面を参照しなが
ら説明する。``Example'' An example of the present invention will be described below with reference to the accompanying drawings.
第１図は本発明の感光体帯電制御方法を説明するための
画像形成装置を示す概略構成図である。FIG. 1 is a schematic configuration diagram showing an image forming apparatus for explaining the photoreceptor charging control method of the present invention.
同図において、画像形成装置は図外の駆動装置により矢
印へ方向へ回転可能に支持された感光体１と、この感光
体１表面を均一に帯電させる帯電器２と、矢印已におい
て記録情報に対応した露光を行い静電潜像を形成する露
光手段と、感光体１に対して対向配置され感光体表面電
位を測定するための電位センサ３と、感光体表面温度を
測定するための温度センサ４と、露光手段により形成さ
れた静電潜像をトナーにより現像する現像器５と、現像
器５により形成された感光体表面のトナー像を図外の搬
送装置により搬送された用紙上へ転写する転写器６と、
転写後の用紙を感光体表面から分離する分離器７と、転
写後の感光体上に残留する残留トナーを清掃するクリー
ニング装置８と、感光体表面の残留電荷を光照射により
除去する除電器９等から構成されている。In the figure, the image forming apparatus includes a photoreceptor 1 supported rotatably in the direction of the arrow by a drive device (not shown), a charger 2 for uniformly charging the surface of the photoreceptor 1, and a charger 2 for uniformly charging the surface of the photoreceptor 1. an exposure means for performing corresponding exposure to form an electrostatic latent image; a potential sensor 3 disposed opposite to the photoreceptor 1 for measuring the surface potential of the photoreceptor; and a temperature sensor for measuring the surface temperature of the photoreceptor. 4, a developer 5 that develops the electrostatic latent image formed by the exposure means with toner, and a toner image formed on the surface of the photoreceptor by the developer 5 to be transferred onto a sheet of paper conveyed by a conveyance device (not shown). a transfer device 6,
A separator 7 that separates paper after transfer from the photoreceptor surface, a cleaning device 8 that cleans residual toner remaining on the photoreceptor after transfer, and a static eliminator 9 that removes residual charge on the photoreceptor surface by light irradiation. It is composed of etc.
ここで、感光体１は拡大して第２図（Ａ）に示すように
感光体層および光導電性絶縁層１ａと導電性支持層１ｂ
を有し、第２図（Ｂ）に示すように抵抗Ｒとコンデンサ
Ｃの並列回路として現すことができる。また、セレン系
の感光体は環境条件が変わると帯電特性、特に感光体の
電荷保持能力が変化することが知られている。例えば、
温度が上昇すると電荷保持能力が低下する。したがって
、電位減衰係数が大きくなり形成される画像の劣化を招
くこととなる。そして、この場合の電位減衰係数の変化
は前記等価回路において抵抗Ｒの変化として考えられる
。Here, the photoreceptor 1 is enlarged and shown as a photoreceptor layer, a photoconductive insulating layer 1a, and a conductive support layer 1b.
It can be expressed as a parallel circuit of a resistor R and a capacitor C as shown in FIG. 2(B). Furthermore, it is known that the charging characteristics of selenium-based photoreceptors, particularly the charge retention ability of the photoreceptor, changes when environmental conditions change. for example,
As the temperature rises, the charge retention ability decreases. Therefore, the potential attenuation coefficient increases, leading to deterioration of the formed image. The change in the potential attenuation coefficient in this case can be considered as a change in the resistance R in the equivalent circuit.
そこで、本発明は感光体１に帯電器２によって測定用の
帯電パターンを形成し、この帯電パターンの表面電位■
０を測定し、この表面電位Ｖｏから実験から求められた
感光体の電位減衰係数ｅｘｐ、（−ｔ／ＲＣ）を算出し
た。Therefore, in the present invention, a charging pattern for measurement is formed on the photoreceptor 1 by a charger 2, and the surface potential of this charging pattern is
0 was measured, and from this surface potential Vo, the potential attenuation coefficient exp, (-t/RC) of the photoreceptor was calculated from the experiment.
したがって、Ｖｔ（を秒後の電位）＝Ｖｏ（初期の電位
）６ｘｐ、（−ｔ／ＲＣ）なる現状の電位減衰係数が算
出される。Therefore, the current potential attenuation coefficient is calculated such that Vt (potential after seconds) = Vo (initial potential) 6xp, (-t/RC).
本実施例ではここで算出された電位減衰係数にしたがっ
て、次のように帯電器の帯電電流を制御する。なお、前
述の帯電器２は図外の制御装置によって印加する帯電電
流を変更することができる。In this embodiment, the charging current of the charger is controlled as follows according to the potential attenuation coefficient calculated here. Note that the charging current applied to the charger 2 described above can be changed by a control device (not shown).
第３図は、実験から求められた感光体の電位減衰係数に
基づく帯電電位と時間との関係を示す関係図である。FIG. 3 is a relationship diagram showing the relationship between charging potential and time based on the potential attenuation coefficient of the photoreceptor determined from experiments.
同図において、時間Ｔにおいて（例えば現像位置で）■
なる電位が必要であり、ある条件下では点線で示す傾き
となる電位減衰係数であったとする。ここで、環境条件
である感光体の温度が電位減衰係数が大きくなったとす
る。このとき、その電位減衰係数による傾きが２点鎖線
で示すように大きくなり、時間Ｔにおいて所望の電位■
が得られなくなる。そこで、２点鎖線で示す傾きの条件
下で、時間Ｔに電位■が（尋られるように帯電器２への
実効的な帯電電流が制御される。いいかえれば、実線で
示すように帯電電位が上昇するように制御する。ここで
、実効的な帯電電流とは感光体ｌに到達する電位量のこ
とを意味し、コロトロンによる放電量、スコロトロンに
よるグリッド間を通過し得る電荷量のことをいう。In the same figure, at time T (for example, at the development position)
Assume that under certain conditions, the potential attenuation coefficient has the slope shown by the dotted line. Here, it is assumed that the temperature of the photoreceptor, which is an environmental condition, causes the potential attenuation coefficient to become large. At this time, the slope due to the potential attenuation coefficient increases as shown by the two-dot chain line, and at time T the desired potential
will not be obtained. Therefore, under the condition of the slope shown by the two-dot chain line, the potential ■ changes at time T (as shown, the effective charging current to the charger 2 is controlled. In other words, the charging potential changes as shown by the solid line). Here, the effective charging current refers to the amount of potential that reaches the photoreceptor l, the amount of discharge by the corotron, and the amount of charge that can pass between grids by the scorotron. .
このようにして、本実施例では画像形成装置における感
光体の帯電器へ印加される電流が制御されるがここで制
御の基礎データとされる感光体表面電位と感光体温度の
検出方法について説明する。In this way, in this embodiment, the current applied to the charger of the photoreceptor in the image forming apparatus is controlled.Here, a method for detecting the photoreceptor surface potential and photoreceptor temperature, which are basic data for control, will be explained. do.
まず、第１図において帯電器２と現像器５の間で露光位
置から外れた位置に電位センサ３が感光体１と対向配置
されている。電位測定が開始されると、感光体１が矢印
六方向へ回転し帯電器２により帯電パターンが形成され
る。この帯電パターンが電位センサ３の検出位置を通過
するとき、感光体の帯電電位が計測される。同時に温度
センサ４により感光体１０表面温度が測定される。この
計測値および温度センサ４により求めた感光体表面温度
による温度補正を行い予め多数の実験結果から求めた感
光体１の暗減衰量のデータから暗減衰量を決定する。決
定された暗減衰量に従って帯電器２の帯電電流を制御す
る。First, in FIG. 1, a potential sensor 3 is disposed between the charger 2 and the developer 5 at a position away from the exposure position, facing the photoreceptor 1. When potential measurement is started, the photoreceptor 1 rotates in the six directions of the arrows, and the charger 2 forms a charging pattern. When this charging pattern passes the detection position of the potential sensor 3, the charging potential of the photoreceptor is measured. At the same time, the temperature sensor 4 measures the surface temperature of the photoreceptor 10. Temperature correction is performed using this measured value and the photoreceptor surface temperature determined by the temperature sensor 4, and the amount of dark attenuation is determined from the data of the amount of dark attenuation of the photoreceptor 1 determined in advance from the results of a large number of experiments. The charging current of the charger 2 is controlled according to the determined amount of dark attenuation.
次に、画像形成装置の動作について説明する。Next, the operation of the image forming apparatus will be explained.
上述した方法により設定された帯電電流により感光体１
表面を均一に帯電器２で帯電する。帯電された表面に矢
印Ｂ位置において記録情報に応じた露光により静電潜像
を形成する。形成された静電潜像は現像器５により内蔵
のトナーで現像される。The photoreceptor 1 is charged by the charging current set by the method described above.
The surface is uniformly charged with a charger 2. An electrostatic latent image is formed on the charged surface at the position of arrow B by exposure according to recorded information. The formed electrostatic latent image is developed by a developing device 5 using built-in toner.
現像された感光体表面のトナー像は図外の搬送装置によ
り送られてくる用紙上に転写器６で転写される。トナー
像の転写された用紙は分離器７により感光体１から分離
され図外の定着器により熱及び圧力で定着される。一方
、感光体１表面の残留トナーはクリーニング装置８によ
り除去され次の帯電工程に備える。The developed toner image on the surface of the photoreceptor is transferred by a transfer device 6 onto a sheet of paper fed by a conveyance device (not shown). The paper onto which the toner image has been transferred is separated from the photoreceptor 1 by a separator 7 and fixed by heat and pressure by a fixing device (not shown). On the other hand, residual toner on the surface of the photoreceptor 1 is removed by a cleaning device 8 in preparation for the next charging process.
なお、本実施例において感光体に温度制御手段を備えて
いない場合について説明したが、感光体に温度制御手段
を備えている場合には、感光体温度を一定とすることが
できるので実験的に得られたデータから温度補正値を一
定とすることができる。In this example, the case where the photoreceptor is not equipped with a temperature control means has been explained, but if the photoreceptor is equipped with a temperature control means, the temperature of the photoreceptor can be kept constant, so experimentally The temperature correction value can be made constant from the obtained data.
「発明の効果」
以上のように構成された本発明の感光体帯電制御方法に
よれば、感光体の減衰特性に影響を与える温度、湿度等
の外乱に対して安定した帯電電流の制御が可能となり良
好な画像を得ることができる。"Effects of the Invention" According to the photoreceptor charging control method of the present invention configured as described above, charging current can be controlled stably against disturbances such as temperature and humidity that affect the attenuation characteristics of the photoreceptor. As a result, a good image can be obtained.
しかも感光体の帯電パターンの測定が１回ですむため、
減衰特性を測定するための待機時間を必要とすることな
く迅速な画像形成が可能となる。Moreover, since the charging pattern of the photoreceptor only needs to be measured once,
Rapid image formation is possible without requiring standby time for measuring attenuation characteristics.
第１図は本発明の感光体帯電制御方法を説明するための
画像形成装置を示す概略構成図、第２図（Ａ）は感光体
の拡大断面図、第２図（Ｂ）は感光体の回路図、第３図
は感光体表面の電位減衰と時間との関係を示す図、第４
図はセレン系感光体の帯電電位と温度との関係を示す図
である。
１・・・・・・感光体、
２・・・・・・帯電器、
３・・・・・・電位センサ、
４・・・・・・温度センサ、
５・・・・・・現像器、
６・・・・・・転写器、
７・・・・・・分離器、
８・・・・・・クリーニング装置、
９・・・・・・除電器。
出願人 富士ゼロックス株式会社代理人
弁理士 山 内 梅 雄第１ 図
第２図
第３図
減衰時間
第４図
仝光値温膣（°Ｃ）FIG. 1 is a schematic configuration diagram showing an image forming apparatus for explaining the photoreceptor charge control method of the present invention, FIG. 2(A) is an enlarged cross-sectional view of the photoreceptor, and FIG. Circuit diagram, Figure 3 is a diagram showing the relationship between potential decay on the surface of the photoreceptor and time, Figure 4
The figure is a diagram showing the relationship between the charging potential and temperature of a selenium-based photoreceptor. 1... Photoreceptor, 2... Charger, 3... Potential sensor, 4... Temperature sensor, 5... Developer, 6...Transfer device, 7...Separator, 8...Cleaning device, 9...Static eliminator. Applicant Fuji Xerox Co., Ltd. Agent
Patent Attorney Umeo Yamanouchi Figure 1 Figure 2 Figure 3 Decay time Figure 4 Light value temperature vagina (°C)
Claims (1)
電パターンを１回測定すると同時に感光体表面温度を測
定し、 その帯電パターンの測定値により得られた帯電効率と感
光体表面温度を基に実験により予め求められたデータか
ら感光体の電位減衰係数を算出し、この電位減衰係数に
したがって帯電器への帯電電流を制御する感光体帯電制
御方法。[Claims] A charging pattern for measurement is formed on the surface of a photoreceptor, this charging pattern is measured once, and at the same time the surface temperature of the photoreceptor is measured, and the charging efficiency and the charging efficiency obtained from the measured values of the charging pattern are measured. A photoconductor charging control method that calculates the potential attenuation coefficient of the photoconductor from data determined in advance through experiments based on the photoconductor surface temperature, and controls the charging current to the charger according to this potential attenuation coefficient.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63056265A JPH01231073A (en) | 1988-03-11 | 1988-03-11 | Method for controlling electrostatic charging of photosensitive body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63056265A JPH01231073A (en) | 1988-03-11 | 1988-03-11 | Method for controlling electrostatic charging of photosensitive body |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01231073A true JPH01231073A (en) | 1989-09-14 |
Family
ID=13022248
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63056265A Pending JPH01231073A (en) | 1988-03-11 | 1988-03-11 | Method for controlling electrostatic charging of photosensitive body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01231073A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6427055B2 (en) * | 2000-05-02 | 2002-07-30 | Ricoh Company, Ltd. | Charge control device for an image forming apparatus which is dependent on ambient temperature |
| US7421218B2 (en) * | 2004-10-20 | 2008-09-02 | Canon Kabushiki Kaisha | Image forming apparatus with surface potential detection |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58125062A (en) * | 1982-01-21 | 1983-07-25 | Konishiroku Photo Ind Co Ltd | Electrostatic recorder |
| JPS58125049A (en) * | 1982-01-20 | 1983-07-25 | Konishiroku Photo Ind Co Ltd | Electrostatic recording device |
| JPS60233671A (en) * | 1984-05-07 | 1985-11-20 | Toshiba Corp | Recorder |
-
1988
- 1988-03-11 JP JP63056265A patent/JPH01231073A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58125049A (en) * | 1982-01-20 | 1983-07-25 | Konishiroku Photo Ind Co Ltd | Electrostatic recording device |
| JPS58125062A (en) * | 1982-01-21 | 1983-07-25 | Konishiroku Photo Ind Co Ltd | Electrostatic recorder |
| JPS60233671A (en) * | 1984-05-07 | 1985-11-20 | Toshiba Corp | Recorder |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6427055B2 (en) * | 2000-05-02 | 2002-07-30 | Ricoh Company, Ltd. | Charge control device for an image forming apparatus which is dependent on ambient temperature |
| US7421218B2 (en) * | 2004-10-20 | 2008-09-02 | Canon Kabushiki Kaisha | Image forming apparatus with surface potential detection |
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