JPH0635260A - Image forming device - Google Patents
Image forming deviceInfo
- Publication number
- JPH0635260A JPH0635260A JP4209723A JP20972392A JPH0635260A JP H0635260 A JPH0635260 A JP H0635260A JP 4209723 A JP4209723 A JP 4209723A JP 20972392 A JP20972392 A JP 20972392A JP H0635260 A JPH0635260 A JP H0635260A
- Authority
- JP
- Japan
- Prior art keywords
- developing bias
- bias voltage
- image
- developing
- toner
- 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
Landscapes
- Dry Development In Electrophotography (AREA)
- Control Or Security For Electrophotography (AREA)
- Developing For Electrophotography (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、複写機、ファクシミ
リ、プリンター等の画像形成装置に係り、詳しくは、帯
電された像担持体面上に走査光等を照射して静電潜像を
形成し、該像担持体面上にトナーを付着させてトナー像
を形成する画像形成装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile and a printer, and more specifically, it irradiates a charged image carrier surface with scanning light or the like to form an electrostatic latent image. The present invention relates to an image forming apparatus which forms a toner image by adhering toner on the surface of the image carrier.
【０００２】[0002]
【従来の技術】近年、画像形成装置において高画質化が
求められているが、その高画質化のためには、特に、低
コントラストの再現性が重要である。低コントラストの
再現性を重視した場合には、像担持体面の地肌部の電位
と現像剤担持体に印加される現像バイアス電圧との差
（現像ポテンシャル）が十分でないと、画像の地肌部に
トナーが付着しやすくなって、トナーの浪費を招くばか
りでなく、地肌汚れとなり、画像の画質を損なうおそれ
がある。2. Description of the Related Art In recent years, image forming apparatuses have been required to have high image quality, and in order to achieve high image quality, reproducibility of low contrast is particularly important. When importance is attached to low-contrast reproducibility, if the difference (developing potential) between the potential of the background portion of the image bearing member surface and the developing bias voltage applied to the developer bearing member is not sufficient, the toner is not transferred to the background portion of the image. Tend to adhere, resulting in not only waste of toner but also background stains, which may impair the image quality of the image.
【０００３】例えば、図２の従来の画像形成装置の概略
構成図に示すように、画像形成動作開始時における像担
持体である感光体ドラム１面上の帯電装置２に対向する
位置から現像担持体である現像ローラ５に対向する位置
までの領域（以下、領域θ1という）は、帯電装置２に
よる帯電が行われないで、現像ローラ５との対向位置を
通過する。例えば、反転現像方式の場合には、領域θ1
が現像ローラ５との対向位置を通過する間、現像ローラ
５に通常の画像形成時の現像バイアス電圧が印加される
ので、領域θ1にトナーが付着してしまう。これによ
り、トナーが無駄に消費されるのみならず、画像形成装
置内の各部でトナー汚染が発生したり、クリーニング装
置（不図示）でクリーニング不良を起こす等の不具合が
生じることがあった。For example, as shown in a schematic configuration diagram of a conventional image forming apparatus of FIG. 2, a developing carrier is carried from a position facing a charging device 2 on a surface of a photosensitive drum 1 which is an image carrier at the start of an image forming operation. A region up to a position facing the developing roller 5 (hereinafter referred to as a region θ 1 ) which is a body passes through a position facing the developing roller 5 without being charged by the charging device 2. For example, in the case of the reversal development method, the area θ 1
Since the developing bias voltage at the time of normal image formation is applied to the developing roller 5 while passing through the position opposite to the developing roller 5, the toner adheres to the region θ 1 . This not only wastes toner, but also causes problems such as toner contamination in various parts of the image forming apparatus and cleaning failure in a cleaning device (not shown).
【０００４】そこで、上記不具合を解決するために、図
３のタイムミングチャートに示すように、感光体ドラム
１の回転駆動（Ｔ1）、現像ローラ５の回転駆動
（Ｔ5）、及び現像バイアス印加装置６による現像ロー
ラ５への現像バイアス電圧の印加（Ｔ6）を制御し、感
光体ドラム１面上の領域θ1が現像ローラ５との対向位
置を通過する間は、通常の画像形成時の現像バイアス電
圧とは逆極性（以下、逆極性という）の現像バイアス電
圧を印加し、感光体ドラム１面上の領域θ1へのトナー
付着を防止する方法が知られている（例えば、特開昭６
１−２９０４５５号公報参照）。Therefore, in order to solve the above problems, as shown in the timing chart of FIG. 3, the photosensitive drum 1 is rotationally driven (T 1 ), the developing roller 5 is rotationally driven (T 5 ), and the developing bias is applied. The application of the developing bias voltage (T 6 ) to the developing roller 5 by the applying device 6 is controlled, and normal image formation is performed while the region θ 1 on the surface of the photosensitive drum 1 passes the position facing the developing roller 5. There is known a method of applying a developing bias voltage having a polarity (hereinafter, referred to as a reverse polarity) opposite to the developing bias voltage at that time to prevent toner adhesion to the region θ 1 on the surface of the photosensitive drum 1 (for example, JP-A-6
No. 1-290455).
【０００５】[0005]
【発明が解決しようとする課題】ところが、上記従来例
の構成によれば、画像形成動作開始時に逆極性の現像バ
イアス電圧を印加する際、現像バイアス印加装置６の特
性により、図４のタイミングチャートに示すように、現
像ローラ５の画像形成動作開始時の現像バイアス電圧の
立ち上がりに傾きが生じるので、現像バイアス電圧が立
ち上がるまでの期間ｔθ2に現像ローラ５に対向する感
光体ドラム１面上の領域（以下、領域θ2という）にお
いて、逆極性の現像バイアス電圧がトナー付着防止に対
して十分な電圧になっていないため、領域θ2上に帯状
のトナー付着が生ずるおそれがあるという問題点があっ
た。However, according to the configuration of the above-described conventional example, when the developing bias voltage having the opposite polarity is applied at the start of the image forming operation, due to the characteristics of the developing bias applying device 6, the timing chart of FIG. As shown in FIG. 3, the rising of the developing bias voltage at the start of the image forming operation of the developing roller 5 has an inclination, and therefore, on the surface of the photosensitive drum 1 facing the developing roller 5 in the period tθ 2 until the developing bias voltage rises. In the area (hereinafter referred to as the area θ 2 ), the developing bias voltage having the opposite polarity is not sufficient to prevent the toner adhesion, so that the belt-shaped toner adhesion may occur on the area θ 2. was there.
【０００６】また、高画質化を達成するためには、ジタ
ーの発生も大きな問題となる。従来から、このジターの
発生を抑えるために、感光体ドラム１の回転をフライホ
イール等を装着することにより安定化させる方法が用い
られている。ところが、フライホイール等を装着する
と、感光体ドラム１回転系のイナーシャが大きくなって
しまう。例えば、図５のタイミングチャートに示すよう
に、感光体ドラム１の回転駆動（Ｔ1）、現像ローラ５
の回転駆動（Ｔ5）、及び現像バイアス印加装置６によ
る現像バイアス電圧の印加（Ｔ6）を制御し、画像形成
動作終了時に感光体ドラム１、現像ローラ５、及び現像
バイアス印加装置６を同時にＯＦＦする。この時、図６
に示すように、現像バイアス印加装置６による逆極性の
現像バイアス電圧の印加が停止された後、感光体ドラム
１回転系のイナーシャにより、感光体ドラム１が角度θ
3だけ回転してしまう。図５のラインＴ1上のうち一点鎖
線で示している期間ｔθ3は、イナーシャによって感光
体ドラム１が回転している期間に相当する。この期間ｔ
θ3においては、逆極性の現像バイアス電圧が現像ロー
ラ５に印加されていないため、期間ｔθ3に現像ローラ
５に対向する感光体ドラム１面上の領域（以下、領域θ
3という）にトナーが付着してしまい、トナーが無駄に
消費されるのみならず、画像形成装置内の各部でトナー
汚染が発生するという問題点もあった。Further, in order to achieve high image quality, the occurrence of jitter is also a serious problem. Conventionally, in order to suppress the occurrence of this jitter, a method of stabilizing the rotation of the photosensitive drum 1 by mounting a flywheel or the like has been used. However, when a flywheel or the like is attached, the inertia of the photosensitive drum 1 rotation system becomes large. For example, as shown in the timing chart of FIG. 5, the photosensitive drum 1 is driven to rotate (T 1 ), the developing roller 5
(T 5 ) and the application of the developing bias voltage (T 6 ) by the developing bias applying device 6 are controlled, and the photosensitive drum 1, the developing roller 5, and the developing bias applying device 6 are simultaneously operated at the end of the image forming operation. Turn off. At this time,
After the application of the developing bias voltage having the reverse polarity by the developing bias applying device 6 is stopped, the inertia of the rotating system of the photosensitive drum 1 causes the photosensitive drum 1 to rotate at an angle θ.
It only rotates by 3 . The period tθ 3 indicated by the alternate long and short dash line on the line T 1 in FIG. 5 corresponds to the period during which the photosensitive drum 1 is rotated by the inertia. This period t
At θ 3 , since the developing bias voltage having the opposite polarity is not applied to the developing roller 5, the region on the surface of the photosensitive drum 1 facing the developing roller 5 (hereinafter, referred to as region θ) during the period tθ 3.
The toner adheres to ( 3 ), and the toner is wastefully consumed, and there is a problem that toner is contaminated in each part in the image forming apparatus.
【０００７】本発明は以上の問題点に鑑みなされたもの
であり、その第１の目的は、コストの上昇や機構上の複
雑化を招くことなく、画像形成動作開始時の像担持体面
上への無駄なトナー付着を防止し、トナーの浪費、廃ト
ナー回収過多及び装置内各部でのトナー汚染のない画像
形成装置を提供することであり、その第２の目的は、コ
ストの上昇や機構上の複雑化を招くことなく、画像形成
動作終了時の像担持体面上への無駄なトナー付着を防止
し、トナーの浪費、廃トナー回収過多及び装置内各部で
のトナー汚染のない画像形成装置を提供することであ
る。The present invention has been made in view of the above problems, and a first object of the present invention is to improve the surface of an image carrier at the start of an image forming operation without increasing the cost and complicating the mechanism. The present invention is to provide an image forming apparatus which prevents unnecessary toner adhesion, waste toner, excessive collection of waste toner, and toner contamination at various parts inside the apparatus. The image forming apparatus prevents unnecessary toner adhesion on the surface of the image carrier at the end of the image forming operation without waste of toner, waste toner excessive collection, and toner contamination in each part of the apparatus without causing complication of the image forming operation. Is to provide.
【０００８】[0008]
【課題を解決するための手段】上記の第１の目的を達成
するために、請求項１の画像形成装置は、像担持体を回
転駆動させる駆動装置と、該像担持体面を一様に帯電す
る帯電装置と、一様帯電された該像担持体面に選択露光
により静電潜像を形成する露光装置と、該静電潜像を現
像剤担持体を介して供給されるトナーによって現像する
現像装置と、該現像剤担持体に現像バイアス電圧を印加
する現像バイアス印加装置とを備えた画像形成装置にお
いて、該現像剤担持体に印加される現像バイアス電圧が
予め設定した値になった後に、該像担持体が動作するよ
うに、該駆動装置及び該現像バイアス印加装置を制御す
る制御手段を設けたことを特徴とするものである。In order to achieve the above-mentioned first object, an image forming apparatus according to a first aspect of the present invention comprises a driving device for rotationally driving an image carrier, and a surface of the image carrier is uniformly charged. Charging device, an exposure device that forms an electrostatic latent image on the surface of the image carrier that is uniformly charged by selective exposure, and a developing process that develops the electrostatic latent image with toner supplied through a developer carrier. In an image forming apparatus including an apparatus and a developing bias applying device that applies a developing bias voltage to the developer carrying member, after the developing bias voltage applied to the developer carrying member reaches a preset value, It is characterized in that a control means for controlling the driving device and the developing bias applying device is provided so that the image carrier operates.
【０００９】また、上記第２の目的を達成するために、
請求項２の画像形成装置は、像担持体を回転駆動する駆
動装置と、該像担持体面を一様に帯電する帯電装置と、
一様帯電された該像担持体面に選択露光により静電潜像
を形成する露光装置と、該静電潜像を現像剤担持体を介
して供給されるトナーによって現像する現像装置と、該
現像剤担持体に現像バイアス電圧を印加する現像バイア
ス印加装置とを備えた画像形成装置において、該像担持
体の回転が停止した後に、該現像剤担持体への現像バイ
アス電圧の印加が停止するように、該駆動装置及び該現
像バイアス印加装置を制御する制御手段を設けたことを
特徴とするものである。In order to achieve the second object,
An image forming apparatus according to a second aspect of the present invention includes a driving device that rotationally drives the image carrier, and a charging device that uniformly charges the surface of the image carrier.
An exposure device that forms an electrostatic latent image on the uniformly charged surface of the image carrier by selective exposure, a developing device that develops the electrostatic latent image with toner supplied via a developer carrier, and the developing device. In an image forming apparatus provided with a developing bias applying device for applying a developing bias voltage to a developer carrier, application of the developing bias voltage to the developer carrier is stopped after the rotation of the image carrier is stopped. In addition, a control means for controlling the driving device and the developing bias applying device is provided.
【００１０】[0010]
【作用】請求項１の画像形成装置によれば、画像形成動
作開始時に、上記制御手段により、上記現像剤担持体に
印加される現像バイアス電圧の大きさが予め設定された
値になった後に、上記像担持体及び上記現像剤担持体の
回転駆動が開始されるように制御される。例えば、反転
現像方式の場合には、通常の画像形成時の現像バイアス
電圧とは逆極性の現像バイアス電圧が該現像剤担持体に
印加され、該逆極性の現像バイアス電圧が予め設定され
た十分大きな値になった後に、該像担持体及び該現像剤
担持体の回転駆動が開始されるように制御される。これ
により、該逆極性のバイアス電圧が十分に立ち上がる前
に、該像担持体及び該現像剤担持体が回転しないように
し、画像形成動作開始時に該像担持体面上に無駄なトナ
ーが付着しないようにするものである。According to the image forming apparatus of the present invention, after the image forming operation is started, the control means causes the magnitude of the developing bias voltage applied to the developer carrying member to reach a preset value. The rotation of the image bearing member and the developer bearing member is controlled to start. For example, in the case of the reversal developing method, a developing bias voltage having a polarity opposite to that of the developing bias voltage at the time of normal image formation is applied to the developer carrying member, and the developing bias voltage having the opposite polarity is set to a sufficient value. After the value becomes large, the rotational driving of the image carrier and the developer carrier is controlled to start. This prevents the image carrier and the developer carrier from rotating before the bias voltage of the opposite polarity rises sufficiently, and prevents useless toner from adhering to the surface of the image carrier at the start of the image forming operation. It is something to do.
【００１１】また、請求項２の画像形成装置によれば、
画像形成動作終了時に、上記制御手段により、上記像担
持体及び上記現像剤担持体の回転駆動を停止させ、その
後の該像担持体の回転系のイナーシャによる該像担持体
の回転が完全に停止した後に、上記現像剤担持体への現
像バイアス電圧の印加、例えば反転現像方式であれば通
常の画像形成時の現像バイアス電圧とは逆極性の現像バ
イアス電圧の印加を停止させるように制御される。これ
により、該像担持体の回転が完全に停止するまで、該現
像剤担持体への該逆極性のバイアス電圧の印加が継続さ
れ、画像形成動作終了時に該像担持体面上に無駄なトナ
ーが付着しないようにするものである。According to the image forming apparatus of claim 2,
At the end of the image forming operation, the control means stops the rotational driving of the image bearing member and the developer bearing member, and thereafter the rotation of the image bearing member is completely stopped by the inertia of the rotation system of the image bearing member. After that, the application of the developing bias voltage to the developer carrying member, for example, in the case of the reversal developing method, is controlled so as to stop the application of the developing bias voltage having a polarity opposite to that of the developing bias voltage during the normal image formation. . As a result, application of the bias voltage of the opposite polarity to the developer carrier is continued until the rotation of the image carrier is completely stopped, and waste toner is left on the surface of the image carrier at the end of the image forming operation. It is to prevent it from adhering.
【００１２】[0012]
【実施例】以下、本発明を画像形成装置である電子写真
複写機（以下、複写機という）に適用した一実施例につ
いて説明する。まず、複写機全体の概略構成及び動作に
ついて説明する。図１は本実施例に係る複写機の概略構
成図である。矢印方向に回転している像担持体である感
光体ドラム１面上の感光体は、帯電装置２のコロナ放電
により一様に正極性に帯電され、図示しないレーザー光
学系等の露光装置により、原稿の画像情報に対応する光
像３が照射され、露光を受けた部分の電位が低下し、感
光体ドラム１面上に静電潜像が形成される。現像装置４
では、この静電潜像の電位低下部分に、現像ローラ５を
介して供給される正極性に帯電されたトナーを静電吸着
させることによって、いわゆる反転現像が行われ、トナ
ー像が形成される。このトナー像は、転写ローラ（不図
示）によって転写紙に転写され、一方、感光体ドラム１
面上にわずかに残ったトナーはクリーニング装置（不図
示）によって除去され、次の帯電に備えられる。DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an electrophotographic copying machine (hereinafter referred to as a copying machine) which is an image forming apparatus will be described below. First, the schematic configuration and operation of the entire copying machine will be described. FIG. 1 is a schematic configuration diagram of a copying machine according to this embodiment. The photosensitive member on the surface of the photosensitive drum 1 which is the image bearing member rotating in the direction of the arrow is uniformly positively charged by the corona discharge of the charging device 2, and is exposed by an exposure device such as a laser optical system not shown. The light image 3 corresponding to the image information of the original is irradiated, the potential of the exposed portion is lowered, and an electrostatic latent image is formed on the surface of the photosensitive drum 1. Developing device 4
Then, so-called reversal development is performed by electrostatically adsorbing the positively charged toner supplied through the developing roller 5 to the portion where the potential of the electrostatic latent image is reduced, and a toner image is formed. . This toner image is transferred onto a transfer sheet by a transfer roller (not shown), while the photosensitive drum 1
The toner slightly left on the surface is removed by a cleaning device (not shown) to prepare for the next charging.
【００１３】次に、本実施例に係る制御手段１２の構成
について説明する。図１に示すように、本実施例に係る
複写機には、感光体ドラム１を回転駆動する駆動装置で
ある駆動モータ８と、現像ローラ５への現像バイアス電
圧を印加する現像バイアス印加装置６と、駆動モータ８
及び現像バイアス印加装置６を制御する制御手段１２と
が設けられている。この制御手段１２は、駆動モータ８
を制御する駆動制御部９と、現像バイアス印加装置６を
制御する現像バイアス制御部７と、駆動制御部９及び現
像バイアス制御部７を制御する主制御部１０とで構成さ
れている。現像バイアス制御部７は、現像バイアス印加
装置６から現像ローラ５へ印加される現像バイアス電圧
の極性、大きさ、印加開始及び停止等を直接制御する。
また、駆動制御部９は、駆動モータ８による感光体ドラ
ム１等の回転駆動の駆動開始及び駆動停止、回転方向、
回転速度等を直接制御する。主制御部１０では、感光体
ドラム１等の回転駆動開始及び停止と現像バイアス印加
開始及び停止とのタイミング制御等が、現像バイアス制
御部７及び駆動制御部９を通して行われる。また、感光
体ドラム１の回転駆動軸８ａと現像ローラ５の回転駆動
軸５ａとの間には、回転駆動伝達部１１が設けられ、現
像ローラ５の回転が感光体ドラム１の回転とが連動する
ようになっている。Next, the structure of the control means 12 according to this embodiment will be described. As shown in FIG. 1, in the copying machine according to this embodiment, a drive motor 8 that is a drive device that rotationally drives the photosensitive drum 1 and a developing bias applying device 6 that applies a developing bias voltage to the developing roller 5. And drive motor 8
And a control means 12 for controlling the developing bias applying device 6. The control means 12 controls the drive motor 8
Drive control section 9 for controlling the developing bias applying apparatus 6, a developing bias control section 7 for controlling the developing bias applying device 6, and a main control section 10 for controlling the driving control section 9 and the developing bias control section 7. The developing bias controller 7 directly controls the polarity, magnitude, start and stop of application of the developing bias voltage applied from the developing bias applying device 6 to the developing roller 5.
Further, the drive control unit 9 starts and stops the driving of the rotation driving of the photosensitive drum 1 and the like by the driving motor 8, the rotation direction,
Directly control the rotation speed. In the main control unit 10, timing control of start and stop of rotation drive of the photosensitive drum 1 and the like and start and stop of application of the developing bias are performed through the developing bias control unit 7 and the drive control unit 9. A rotary drive transmission unit 11 is provided between the rotary drive shaft 8a of the photosensitive drum 1 and the rotary drive shaft 5a of the developing roller 5, and the rotation of the developing roller 5 is linked with the rotation of the photosensitive drum 1. It is supposed to do.
【００１４】次に、本実施例に係る複写機の画像形成動
作開始時における制御について説明する。図７は、本実
施例に係る複写機における現像バイアス電圧とトナー付
着量との関係を示す特性図である。図８は、本実施例に
係る複写機の画像形成動作開始時における概略構成図で
ある。画像形成動作開始時における感光体ドラム１面上
の帯電装置２に対向する位置から現像ローラ５に対向す
る位置までの領域θ1は、帯電装置２による帯電が行わ
れていない。この領域θ1への無駄なトナー付着を防止
するために、領域θ1に対して通常の画像形成時の現像
バイアス電圧とは逆極性の現像バイアス電圧を現像ロー
ラ５に印加してするが、図７の斜線部からわかるよう
に、０Ｖから−２００Ｖ程度までは感光体ドラム１面の
領域θ1上に無駄なトナーが付着し、多量の地肌汚れが
発生してしまう。そこで、本実施例では、高画質化のた
めに低コントラストの再現性を向上させ、かつ、図８の
領域θ1に無駄なトナーを付着させないように、画像形
成動作開始時に現像ローラ５に印加する逆極性の現像バ
イアス電圧の大きさを−２５０Ｖに設定している。Next, the control at the start of the image forming operation of the copying machine according to this embodiment will be described. FIG. 7 is a characteristic diagram showing the relationship between the developing bias voltage and the toner adhesion amount in the copying machine according to this embodiment. FIG. 8 is a schematic configuration diagram at the start of the image forming operation of the copying machine according to this embodiment. The region θ 1 on the surface of the photosensitive drum 1 from the position facing the charging device 2 to the position facing the developing roller 5 at the start of the image forming operation is not charged by the charging device 2. To prevent unnecessary toner adhesion to the region theta 1, the developing bias voltage of the normal image forming time for the region theta 1 will be by applying a developing bias voltage of the opposite polarity to the developing roller 5, As can be seen from the shaded area in FIG. 7, from 0 V to about −200 V, useless toner adheres to the area θ 1 on the surface of the photosensitive drum 1 and a large amount of background stain occurs. Therefore, in this embodiment, the reproducibility of low contrast is improved for high image quality, and the toner is applied to the developing roller 5 at the start of the image forming operation so as to prevent unnecessary toner from adhering to the area θ 1 in FIG. The magnitude of the reverse bias developing bias voltage is set to -250V.
【００１５】また、図９は、本実施例に係る複写機にお
ける画像形成動作開始時の現像バイアス電圧の時間変化
を示す特性図である。図９からわかるように、地肌汚れ
が発生しない逆極性の現像バイアス電圧（−２００Ｖ）
になるまでには約０.１秒を要し、予め設定した上記逆
極性の現像バイアス電圧（−２５０Ｖ）になるまでには
約０.１５秒を要する。そこで、本実施例では、画像形
成動作開始時において、図８の現像バイアス電圧が立ち
上がるまでの期間ｔθ2に現像ローラ５に対向する感光
体ドラム１面上の領域θ2に無駄なトナーを付着させな
いように、図１０のフローチャート及び図１１のタイミ
ングチャートに示すような感光体ドラム１の回転駆動
（Ｔ1）、現像ローラ５の回転駆動（Ｔ5）及び現像ロー
ラ５への現像バイアス電圧の印加（Ｔ6）の制御を行っ
ている。まず、現像ローラ５への逆極性の現像バイアス
電圧の印加を開始し、主制御部１０に設けたタイマ−Ｔ
をリセットする（図１０のステップ１及びステップ２
２）。次に、その電圧印加開始から０.１秒後に、すな
わちタイマーＴが０.１秒になった後に、感光体ドラム
１及び現像ローラ５の回転駆動を開始する（ステップ３
及びステップ４）。FIG. 9 is a characteristic diagram showing the change over time of the developing bias voltage at the start of the image forming operation in the copying machine according to this embodiment. As can be seen from FIG. 9, the reverse polarity developing bias voltage (-200V) in which the background stain does not occur.
It takes about 0.1 seconds to reach the predetermined value, and about 0.15 seconds to reach the preset reverse polarity developing bias voltage (-250 V). Therefore, in the present embodiment, when the image forming operation is started, useless toner is attached to the region θ 2 on the surface of the photosensitive drum 1 facing the developing roller 5 during the period tθ 2 until the developing bias voltage in FIG. 8 rises. In order to prevent this, the rotational drive of the photosensitive drum 1 (T 1 ), the rotational drive of the developing roller 5 (T 5 ), and the developing bias voltage applied to the developing roller 5 as shown in the flowchart of FIG. 10 and the timing chart of FIG. The application (T 6 ) is controlled. First, the application of the developing bias voltage having the opposite polarity to the developing roller 5 is started, and the timer-T provided in the main controller 10 is started.
Is reset (Step 1 and Step 2 in FIG. 10)
2). Next, after 0.1 second from the start of the voltage application, that is, after the timer T reaches 0.1 second, the rotational driving of the photosensitive drum 1 and the developing roller 5 is started (step 3).
And step 4).
【００１６】なお、図示していないが、帯電装置２によ
る感光体ドラム１面の帯電は、感光体ドラム１及び現像
ローラ５のＯＮと同時、又は数秒後に開始される。その
後、該帯電領域の先端が露光装置（不図示）による照射
位置を通過した後、該露光装置がＯＮされ、さらに、該
帯電領域の先端が現像ローラ５に対向する位置に達する
直前に、現像バイアス電圧を逆極性から通常の画像形成
時の極性の現像バイアス電圧へ切り替えられ、該帯電領
域が現像ローラ５に対向するときには、現像バイアス電
圧が通常の画像形成時の極性の現像バイアス電圧の大き
さまで十分立ち上がった状態で現像ローラ５に印加され
る。Although not shown, the charging of the surface of the photosensitive drum 1 by the charging device 2 is started at the same time as when the photosensitive drum 1 and the developing roller 5 are turned on, or after several seconds. After that, the exposure device is turned on after the tip of the charging region has passed the irradiation position by the exposure device (not shown), and immediately before the tip of the charging region reaches the position facing the developing roller 5, development is performed. When the bias voltage is switched from the reverse polarity to the developing bias voltage having the polarity at the time of normal image formation, and the charging area faces the developing roller 5, the developing bias voltage is the magnitude of the developing bias voltage at the time of normal image formation. It is applied to the developing roller 5 in a state in which it has sufficiently risen.
【００１７】次に、本実施例の画像形成動作開始時にお
けるトナー付着の結果を従来例での結果と共に示す。面
積率６％の原稿を用いた場合、従来のように、現像ロー
ラ５に逆極性の現像バイアス電圧を印加すると同時に、
感光体ドラム１及び現像ローラ５の回転動作を開始した
場合には、原稿１枚当りのトナー消費量は４０.０ mg／
枚であり、１枚当りの廃トナー回収量は２０.８ mg／枚
であった。一方、本実施例に係る上記画像形成動作開始
時における制御を行ったところ、原稿１枚当りのトナー
消費量は２３.８ mg／枚に、１枚当りの廃トナー回収量
は４.６ mg／枚にそれぞれ低減された。それぞれ低減率
にすると、１枚当りのトナー消費量で約４０％、１枚当
りの廃トナー回収量で約７８％であった。Next, the result of toner adhesion at the start of the image forming operation of this embodiment will be shown together with the result of the conventional example. When an original having an area ratio of 6% is used, a developing bias voltage having a reverse polarity is applied to the developing roller 5 as in the conventional case, and at the same time,
When the rotation operation of the photoconductor drum 1 and the developing roller 5 is started, the toner consumption amount per original is 40.0 mg /
The amount of waste toner collected per sheet was 20.8 mg / sheet. On the other hand, when the control at the start of the image forming operation according to the present embodiment is performed, the toner consumption amount per original is 23.8 mg / sheet, and the waste toner recovery amount per sheet is 4.6 mg. It was reduced to / sheet respectively. When the respective reduction rates are set, the toner consumption amount per sheet is about 40%, and the waste toner recovery amount per sheet is about 78%.
【００１８】以上、本実施例に係る上記画像形成動作開
始時の制御によれば、逆極性のバイアス電圧が十分に立
ち上がる前に、感光体ドラム１及び現像ローラ５が回転
しないように制御し、画像形成動作開始時に感光体ドラ
ム１面上に無駄なトナーが付着しないようにしているの
で、コストや機構上の複雑化を招くことなく、トナーの
浪費や複写機各部でのトナー汚染を有効に防止できる。As described above, according to the control at the start of the image forming operation according to the present embodiment, the photosensitive drum 1 and the developing roller 5 are controlled so as not to rotate before the bias voltage of the reverse polarity rises sufficiently. Since unnecessary toner is prevented from adhering to the surface of the photosensitive drum 1 at the time of starting the image forming operation, waste of toner and toner contamination in each part of the copying machine can be effectively performed without causing cost and mechanism complication. It can be prevented.
【００１９】次に、本実施例に係る画像形成動作終了時
における制御について説明する。本実施例では、感光体
ドラム１の回転軸上に回転を安定化させるためのフライ
ホイール（不図示）を装着している。このフライホイー
ルを装着した状態では、画像形成動作終了時に、感光体
ドラム１回転系のイナーシャにより、感光体ドラム１の
回転が完全に停止するまでに１秒要してしまう。そこ
で、本実施例では、高画質化のために低コントラストの
再現性を向上させ、かつ、回転駆動停止後イナーシャに
より感光体ドラム１が回転している期間ｔθ3に現像ロ
ーラ５に対向する感光体ドラム１面上の領域θ3に無駄
なトナーを付着させないように、図１２のフローチャー
ト及び図１３のタイミングチャートに示すような感光体
ドラム１の回転駆動（Ｔ1）、現像ローラ５の回転駆動
（Ｔ5）及び現像ローラ５への現像バイアス電圧の印加
（Ｔ6）の制御を行っている。まず、感光体ドラム１及
び現像ローラ５の回転駆動を停止し、主制御部１０に設
けたタイマ−Ｔをリセットする（図１２のステップ１及
びステップ２）。次に、現像ローラ５への逆極性の現像
バイアス電圧の印加を１秒間継続させ、感光体ドラム１
の回転が完全に停止した後に、すなわちタイマーＴが
０.１秒になった後に、現像ローラ５への逆極性の現像
バイアス電圧の印加を解除する（ステップ３及びステッ
プ４）。Next, the control at the end of the image forming operation according to this embodiment will be described. In this embodiment, a flywheel (not shown) for stabilizing the rotation is mounted on the rotary shaft of the photosensitive drum 1. With this flywheel attached, it takes one second to completely stop the rotation of the photosensitive drum 1 due to the inertia of the rotating system of the photosensitive drum 1 at the end of the image forming operation. In view of this, in this embodiment, the reproducibility of low contrast is improved for higher image quality, and the photoconductor that faces the developing roller 5 during the period tθ 3 during which the photoconductor drum 1 is rotated by inertia after rotation is stopped. In order to prevent unnecessary toner from adhering to the area θ 3 on the surface of the body drum 1, the photosensitive drum 1 is rotationally driven (T 1 ) and the developing roller 5 is rotated as shown in the flowchart of FIG. 12 and the timing chart of FIG. The drive (T 5 ) and the application of the developing bias voltage to the developing roller 5 (T 6 ) are controlled. First, the rotational driving of the photoconductor drum 1 and the developing roller 5 is stopped, and the timer-T provided in the main controller 10 is reset (steps 1 and 2 in FIG. 12). Next, the application of the developing bias voltage having the opposite polarity to the developing roller 5 is continued for 1 second, and the photosensitive drum 1
After the rotation of No. 1 is completely stopped, that is, after the timer T reaches 0.1 seconds, the application of the developing bias voltage having the reverse polarity to the developing roller 5 is released (steps 3 and 4).
【００２０】なお、図示していないが、上記工程に先立
って、帯電装置２による感光体ドラム１面の帯電が停止
され、帯電領域の後端が露光装置（不図示）による照射
位置を通過する直前に該露光装置がＯＦＦされ該帯電領
域の後端が現像ローラ５に対向する位置に達した後に、
現像バイアス電圧が通常の画像形成時の極性から逆極性
へ切り替えられる。Although not shown, prior to the above step, the charging of the surface of the photosensitive drum 1 by the charging device 2 is stopped, and the rear end of the charging area passes through the irradiation position of the exposure device (not shown). Immediately before the exposure device is turned off and the rear end of the charging area reaches the position facing the developing roller 5,
The developing bias voltage is switched from the normal polarity during image formation to the reverse polarity.
【００２１】次に、本実施例の画像形成動作終了時にお
けるトナー付着の結果を従来例での結果と共に示す。面
積率６％の原稿を用いた場合、従来のように、感光体ド
ラム１及び現像ローラ５の回転駆動動作の終了と同時
に、現像ローラ５に逆極性の現像バイアス電圧を印加を
解除した場合には、原稿１枚当りのトナー消費量は５
２.７ mg／枚であり、１枚当りの廃トナー回収量は３
３.５ mg／枚であった。一方、本実施例に係る上記画像
形成動作終了時における制御を行ったところ、原稿１枚
当りのトナー消費量は２３.９ mg／枚に、１枚当りの廃
トナー回収量は４.７ mg／枚にそれぞれ低減された。そ
れぞれ低減率にすると、１枚当りのトナー消費量で約５
５％、１枚当りの廃トナー回収量で約８６％であり、感
光体ドラム１の回転を安定化するためのフライホイール
の装着によるトナー消費量及び廃トナー回収量の増加を
大幅に低減することができた。Next, the result of toner adhesion at the end of the image forming operation of this embodiment will be shown together with the result of the conventional example. When an original having an area ratio of 6% is used, as in the conventional case, when the application of the developing bias voltage having the opposite polarity to the developing roller 5 is canceled at the same time as the rotation driving operation of the photosensitive drum 1 and the developing roller 5 is completed. Is, the toner consumption per original is 5
2.7 mg / sheet, and the amount of waste toner collected per sheet is 3
It was 3.5 mg / sheet. On the other hand, when the control at the end of the image forming operation according to the present embodiment is performed, the toner consumption amount per original is 23.9 mg / sheet, and the waste toner recovery amount per sheet is 4.7 mg. It was reduced to / sheet respectively. When each reduction rate is used, the toner consumption per sheet is about 5
5%, the amount of waste toner collected per sheet is about 86%, and the increase in the amount of toner consumed and the amount of waste toner collected due to the installation of the flywheel for stabilizing the rotation of the photosensitive drum 1 is greatly reduced. I was able to.
【００２２】以上、本実施例の上記画像形成動作終了時
の制御によれば、画像品質の向上のために感光体ドラム
１の回転軸上にフライホイール等を装着して回転を安定
化させる手段により画像形成動作終了時の感光体ドラム
１の回転系のイナーシャが大きくなったような場合であ
っても、感光体ドラム１の回転が完全に停止するまで、
現像ローラ５への逆極性のバイアス電圧の印加が継続さ
れ、画像形成動作終了時に感光体ドラム１面上に無駄な
トナーが付着しないようになるので、コストや機構上の
複雑化を招くことなく、トナーの浪費や複写機各部での
トナー汚染を有効に防止できる。As described above, according to the control at the end of the image forming operation of the present embodiment, a means for stabilizing the rotation by mounting a flywheel or the like on the rotation shaft of the photosensitive drum 1 in order to improve the image quality. Therefore, even when the inertia of the rotation system of the photoconductor drum 1 at the end of the image forming operation becomes large, until the rotation of the photoconductor drum 1 is completely stopped,
The bias voltage of the reverse polarity is continuously applied to the developing roller 5, and unnecessary toner is prevented from adhering to the surface of the photosensitive drum 1 at the end of the image forming operation. Therefore, cost and mechanism are not complicated. Therefore, waste of toner and toner contamination in each part of the copying machine can be effectively prevented.
【００２３】なお、本実施例では、露光後の感光体ドラ
ム１面上の静電潜像において表面電位が低下した部分
（原稿の文字部）にトナーを付着させる反転現像方式の
場合を例示したが、本発明は反転現像方式に限定される
ものでなく、露光後の感光体ドラム１面上の静電潜像に
おいて表面電位が低下していない部分（原稿の文字部）
にトナーを付着させる正規現像方式等の他の現像方式に
も適用できるものである。例えば、正規現像方式におけ
る画像形成動作開始時では、まず、現像バイアス印加装
置６がＯＮされ、通常の画像形成時の現像バイアス電圧
が現像ローラ５に印加され、現像バイアス電圧が十分に
立ち上がったタイミングで、感光体ドラム１及び現像ロ
ーラ５の回転駆動が開始される。In this embodiment, the case of the reversal development method in which the toner is adhered to the portion (text portion of the original document) where the surface potential is lowered in the electrostatic latent image on the surface of the photosensitive drum 1 after exposure is exemplified. However, the present invention is not limited to the reversal development method, and a portion where the surface potential is not lowered in the electrostatic latent image on the surface of the photosensitive drum 1 after exposure (character portion of the original)
It can also be applied to other developing methods such as a regular developing method in which toner is adhered to. For example, at the start of the image forming operation in the regular developing method, first, the developing bias applying device 6 is turned on, the developing bias voltage at the time of normal image forming is applied to the developing roller 5, and the timing when the developing bias voltage rises sufficiently. Then, the rotational driving of the photosensitive drum 1 and the developing roller 5 is started.
【００２４】また、本実施例に係る複写機では、画像形
成動作開始時において、現像ローラ５への逆極性の現像
バイアス電圧の印加開始から感光体ドラム１及び現像ロ
ーラ５の回転駆動の開始までの時間を０.１秒に、画像
形成動作終了時において、感光体ドラム１及び現像ロー
ラ５の回転駆動停止から現像ローラ５への逆極性の現像
バイアス電圧の印加停止までの時間を１秒に設定してい
るが、これらの時間設定値は絶対的な値ではなく、複写
機に用いる現像バイアス印加装置６や駆動モータ８の種
類に応じて変わってくる相対的な値であり、その使用す
る複写機に適した設定値を用いることができる。Further, in the copying machine according to the present embodiment, at the start of the image forming operation, from the start of the application of the developing bias voltage of the opposite polarity to the developing roller 5 to the start of the rotational driving of the photosensitive drum 1 and the developing roller 5. Is 0.1 seconds, and at the end of the image forming operation, the time from the stop of the rotation drive of the photosensitive drum 1 and the developing roller 5 to the stop of the application of the developing bias voltage of the opposite polarity to the developing roller 5 is set to 1 second. Although set, these time setting values are not absolute values, but relative values that change depending on the types of the developing bias applying device 6 and the drive motor 8 used in the copying machine, and are used. A setting value suitable for the copying machine can be used.
【００２５】また、本実施例では、画像形成動作開始時
に逆極性の現像バイアス電圧が予め設定した値になった
時点、及び画像形成動作終了時に感光体ドラム１及び現
像ローラ５が完全に停止した時点を、それぞれ予め設定
した時間設定値（０.１秒，１秒）が経過したかどうか
で判断しているが、それぞれ、現像バイアス電圧の立ち
上がり及び感光体ドラムの回転をモニターして判断する
ようにしても良い。In the present embodiment, the photosensitive drum 1 and the developing roller 5 are completely stopped when the developing bias voltage having the opposite polarity reaches a preset value at the start of the image forming operation and at the end of the image forming operation. The time point is judged by whether or not a preset time set value (0.1 second, 1 second) has passed, respectively, and each judgment is made by monitoring the rising of the developing bias voltage and the rotation of the photosensitive drum. You may do it.
【００２６】[0026]
【発明の効果】請求項１の画像形成装置によれば、上記
制御手段により、上記逆極性のバイアス電圧が十分に立
ち上がる前に、上記像担持体及び上記現像剤担持体が回
転しないようにし、画像形成動作開始時に該像担持体面
上に無駄なトナーが付着しないようにしているので、コ
ストや機構上の複雑化を招くことなく、トナーの浪費や
画像形成装置の各部でのトナー汚染を有効に防止できる
という優れた効果がある。According to the image forming apparatus of the present invention, the control means prevents the image carrier and the developer carrier from rotating before the bias voltage of the reverse polarity rises sufficiently. Since unnecessary toner is prevented from adhering to the surface of the image carrier at the start of the image forming operation, waste of toner and toner contamination in each part of the image forming apparatus are effective without incurring cost and mechanism complexity. It has an excellent effect that it can be prevented.
【００２７】請求項２の画像形成装置によれば、上記制
御手段により、上記像担持体の回転が完全に停止するま
で、上記現像剤担持体へ上記逆極性のバイアス電圧の印
加が継続され、画像形成動作終了時に該像担持体面上に
無駄なトナーが付着しないようにしているので、画像品
質の向上のために該像担持体の回転軸上にフライホイー
ル等を装着して回転を安定化させる手段により画像形成
動作終了時の該像担持体の回転系のイナーシャが大きく
なったような場合であっても、コストや機構上の複雑化
を招くことなく、トナーの浪費や画像形成装置の各部で
のトナー汚染を有効に防止できるという優れた効果があ
る。According to another aspect of the image forming apparatus of the present invention, the control means continues to apply the reverse bias voltage to the developer carrier until the rotation of the image carrier is completely stopped. To prevent unnecessary toner from adhering to the surface of the image carrier at the end of the image forming operation, a flywheel or the like is mounted on the rotation shaft of the image carrier to stabilize the rotation in order to improve image quality. Even if the inertia of the rotation system of the image carrier at the end of the image forming operation is increased by the means for causing the image forming operation, the cost of the toner and the complexity of the mechanism are not increased, and the waste of toner and the image forming apparatus are prevented. There is an excellent effect that toner contamination in each part can be effectively prevented.
【図１】本実施例に係る複写機の概略構成図。FIG. 1 is a schematic configuration diagram of a copying machine according to an embodiment.
【図２】従来の複写機の画像形成動作開始時の概略構成
図。FIG. 2 is a schematic configuration diagram at the start of an image forming operation of a conventional copying machine.
【図３】従来の複写機の画像形成動作開始時におけるタ
イミングチャート。FIG. 3 is a timing chart at the start of an image forming operation of a conventional copying machine.
【図４】図３の現像バイアス電圧の立ち上がりの傾きを
考慮したタイミングチャート。FIG. 4 is a timing chart in which a rising slope of the developing bias voltage in FIG. 3 is taken into consideration.
【図５】従来の複写機の画像形成動作終了時におけるタ
イミングチャート。FIG. 5 is a timing chart at the end of the image forming operation of the conventional copying machine.
【図６】従来の複写機の画像形成動作終了時の概略構成
図。FIG. 6 is a schematic configuration diagram at the end of an image forming operation of a conventional copying machine.
【図７】本実施例に係る複写機における現像バイアス電
圧とトナー付着量との関係を示す特性図。FIG. 7 is a characteristic diagram showing a relationship between a developing bias voltage and a toner adhesion amount in the copying machine according to the present embodiment.
【図８】本実施例に係る複写機の画像形成動作開始時に
おける概略構成図。FIG. 8 is a schematic configuration diagram when the image forming operation of the copying machine according to the present embodiment is started.
【図９】本実施例に係る複写機の画像形成動作開始時に
おける現像バイアス電圧の時間変化を示す特性図。FIG. 9 is a characteristic diagram showing a change with time of the developing bias voltage at the start of the image forming operation of the copying machine according to the present embodiment.
【図１０】本実施例に係る複写機の画像形成動作開始時
における制御のフローチャート。FIG. 10 is a flowchart of control at the start of the image forming operation of the copying machine according to this embodiment.
【図１１】本実施例に係る複写機の画像形成動作開始時
におけるタイミングチャート。FIG. 11 is a timing chart at the start of the image forming operation of the copying machine according to the present embodiment.
【図１２】本実施例に係る複写機の画像形成動作終了時
における制御のフローチャート。FIG. 12 is a flowchart of control at the end of the image forming operation of the copying machine according to this embodiment.
【図１３】本実施例に係る複写機の画像形成動作終了時
におけるタイミングチャート。FIG. 13 is a timing chart at the end of the image forming operation of the copying machine according to the present embodiment.
１ 感光体ドラム ２ 帯電装置 ４ 現像装置 ５ 現像ローラ ６ 現像バイアス印加装置 ７ 現像バイアス制御部 ８ 駆動モータ ９ 駆動制御部 １０ 主制御部 DESCRIPTION OF SYMBOLS 1 Photoconductor drum 2 Charging device 4 Developing device 5 Developing roller 6 Developing bias applying device 7 Developing bias control section 8 Drive motor 9 Drive control section 10 Main control section
Claims (2)
像担持体面を一様に帯電する帯電装置と、一様帯電され
た該像担持体面に選択露光により静電潜像を形成する露
光装置と、該静電潜像を現像剤担持体を介して供給され
るトナーによって現像する現像装置と、該現像剤担持体
に現像バイアス電圧を印加する現像バイアス印加装置と
を備えた画像形成装置において、 該現像剤担持体に印加される現像バイアス電圧が予め設
定した値になった後に、該像担持体が動作するように、
該駆動装置及び該現像バイアス印加装置を制御する制御
手段を設けたことを特徴とする画像形成装置。1. A drive device for rotationally driving an image carrier, a charging device for uniformly charging the surface of the image carrier, and an electrostatic latent image formed on the surface of the uniformly charged image carrier by selective exposure. Image formation including an exposure device, a developing device that develops the electrostatic latent image with toner supplied through a developer carrier, and a developing bias applying device that applies a developing bias voltage to the developer carrier. In the apparatus, after the developing bias voltage applied to the developer carrier reaches a preset value, the image carrier is operated so as to operate.
An image forming apparatus comprising a control unit for controlling the drive unit and the developing bias applying unit.
担持体面を一様に帯電する帯電装置と、一様帯電された
該像担持体面に選択露光により静電潜像を形成する露光
装置と、該静電潜像を現像剤担持体を介して供給される
トナーによって現像する現像装置と、該現像剤担持体に
現像バイアス電圧を印加する現像バイアス印加装置とを
備えた画像形成装置において、 該像担持体の回転が停止した後に、該現像剤担持体への
現像バイアス電圧の印加が停止するように、該駆動装置
及び該現像バイアス印加装置を制御する制御手段を設け
たことを特徴とする画像形成装置。2. A drive device for rotationally driving an image carrier, a charging device for uniformly charging the surface of the image carrier, and an electrostatic latent image formed on the surface of the uniformly charged image carrier by selective exposure. Image formation including an exposure device, a developing device that develops the electrostatic latent image with toner supplied through a developer carrier, and a developing bias applying device that applies a developing bias voltage to the developer carrier. In the apparatus, control means for controlling the driving device and the developing bias applying device is provided so that the application of the developing bias voltage to the developer carrying member is stopped after the rotation of the image bearing member is stopped. An image forming apparatus characterized by.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04209723A JP3139845B2 (en) | 1992-07-14 | 1992-07-14 | Image forming device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04209723A JP3139845B2 (en) | 1992-07-14 | 1992-07-14 | Image forming device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0635260A true JPH0635260A (en) | 1994-02-10 |
| JP3139845B2 JP3139845B2 (en) | 2001-03-05 |
Family
ID=16577585
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP04209723A Expired - Fee Related JP3139845B2 (en) | 1992-07-14 | 1992-07-14 | Image forming device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3139845B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008089942A (en) * | 2006-10-02 | 2008-04-17 | Canon Inc | Image forming apparatus |
| JP2017009865A (en) * | 2015-06-24 | 2017-01-12 | コニカミノルタ株式会社 | Image forming apparatus |
| JP2017026679A (en) * | 2015-07-16 | 2017-02-02 | コニカミノルタ株式会社 | Image forming apparatus |
-
1992
- 1992-07-14 JP JP04209723A patent/JP3139845B2/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008089942A (en) * | 2006-10-02 | 2008-04-17 | Canon Inc | Image forming apparatus |
| JP2017009865A (en) * | 2015-06-24 | 2017-01-12 | コニカミノルタ株式会社 | Image forming apparatus |
| JP2017026679A (en) * | 2015-07-16 | 2017-02-02 | コニカミノルタ株式会社 | Image forming apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3139845B2 (en) | 2001-03-05 |
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