JP4190226B2

JP4190226B2 - Image forming apparatus

Info

Publication number: JP4190226B2
Application number: JP2002221805A
Authority: JP
Inventors: 直之岡本
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 2002-07-30
Filing date: 2002-07-30
Publication date: 2008-12-03
Anticipated expiration: 2022-07-30
Also published as: JP2004061962A

Description

【０００１】
【発明の属する技術分野】
本発明は、情報出力端末機器に関し、より詳細には、プリンタ、複写機、ファクシミリ等の画像形成装置に関するものである。
【０００２】
【従来の技術】
本発明の従来技術として、定着装置で無端状帯体の加熱ローラと、これに加圧される加圧ローラとを備えるものがあり、このような定着装置において、加熱ローラ又は加圧ローラの離型性が不良である際には、一部のトナーが定着ローラ又は加圧ローラに付着してオフセットが発生する虞れがあるため、良好な離型性が得られるよう、これらの外周に離型層を形成し、更にこの離型層にオフセット防止液を塗布する塗布ローラを設けたものが公知となっている。
【０００３】
【発明が解決しようとする課題】
しかしながら、上記従来技術には、オフセットの発生を完全に防止することが困難であるため、微量なオフセットが加熱ローラや加圧ローラに残留して、塗布ローラの表面や塗布ローラに接するオフセット防止液供給部分をトナーや紙粉で汚損し、結果的に、経時使用によっては塗布ローラによる塗布量が低下すると共に表面が汚損されることにより、塗布ローラの汚損が加熱ローラや加圧ローラに逆転写されて記録紙に画像汚れを発生させるという問題がある。
【０００４】
又、近年、紙のリサイクル化や紙の白色度を向上させるために使用される充填材（填料）等の影響によって、オフセット防止液を供給する塗布ローラやオフセット防止液供給口に付着堆積する紙粉量の増加が目立ってきており、この紙粉が多くなると、トナーの粘着性により、クリーニングローラで回収しきれない汚損物が塗布ローラの表面に残留するようになり、塗布ローラの性能低下や、画像品質の低下を招くという問題があった。
【０００５】
そこで本発明は上記の問題点を解決するためになされたもので、塗布ローラの表面やオフセット防止液供給部分に紙粉を残留させることがなく、塗布ローラの性能低下を防止することができ、同時に塗布ローラから異物が加熱ローラに逆転写することがなく、画像品質の低下を防止する画像形成装置を提供することを目的とする。
【０００６】
【課題を解決するための手段】
前記課題を解決するために、本発明の画像形成装置は、発熱体を備えた無端状帯体と、該無端状帯体に加圧された加圧ローラと、前記無端状帯体または、前記加圧ローラの内、少なくとも前記無端状帯体にオフセット防止液を塗布する塗布ローラとを有し、前記無端状帯体と前記加圧ローラとの間にトナー像が形成された記録材を通紙させて当該用紙にトナー像を定着する定着装置を用い、前記記録材に画像を形成する画像形成装置において、前記塗布ローラのクリーニング部材を、前記記録材への画像形成時に前記塗布ローラが回転する方向とは逆の回転に対してはカウンタ状態となるように、前記無端状帯体と前記塗布ローラの接触部より下流側でかつ、前記塗布ローラとオフセット防止液供給口との接触部より上流側に設け、前記クリーニング部材は、前記記録材への画像形成時には前記塗布ローラから離間しており、前記記録材への画像形成動作が終了した後に、前記画像形成動作時の前記各ローラ回転方向と逆の回転方向に、前記各ローラを回転させることによって、前記クリーニング部材を前記塗布ローラと当接させることを特徴とする。
【０００７】
また、本発明の画像形成装置において、前記クリーニング部材が、前記塗布ローラの画像形成動作時と逆の回転と連動して前記塗布ローラに当接するようにしてもよい。
【０００８】
また、本発明の画像形成装置において、前記記録材への画像形成動作が終了した後、前記塗布ローラのオフセット防止液供給口に位置する個所が前記クリーニング部材を設けた位置を通過する回転量以上、前記画像形成動作時の前記各ローラ回転方向と逆の回転方向に、前記各ローラを回転させるよう構成してもよい。
【０００９】
また、本発明の画像形成装置において、前記記録材への画像形成動作が終了した後、前記画像形成動作時の前記各ローラ回転方向と逆の回転方向に、前記各ローラの回転動作を行い、その後、前記画像形成動作時の前記各ローラ回転方向に、前記逆転時の回転量以上、前記各ローラが回転する動作を設けてもよい。
【００１０】
【発明の実施の形態】
以下、図面により本発明の実施の形態を詳細に説明する。図１は本発明の実施の形態の画像形成装置を示す概略図あり、図２は、塗布ローラを詳細に示す拡大図である。
【００１１】
図１、図２において、画像形成装置は、発熱体を備えた無端状帯体の加熱ローラ１と、加熱ローラ１に加圧された加圧ローラ２と、加熱ローラ１または加圧ローラ２の内、少なくとも加熱ローラ１にオフセット防止液を塗布する塗布ローラ３とを有し、この加熱ローラ１と加圧ローラ２との間にはトナー像が形成された記録材を通紙させて当該用紙にトナー像を定着する定着装置を用い、記録材に画像を形成するように構成し、各ローラ１，２，３は、記録材への画像形成動作が終了した後、画像形成動作時の各回転方向と逆の回転方向に、回転するように構成されている。
【００１２】
又、塗布ローラ３の側面には、オフセット防止液４を供給するオフセット防止液供給口５と、クリーニング部材６とを備え、クリーニング部材６は、加熱ローラ１と塗布ローラ３の接触部の下流側に位置すると共に塗布ローラ３とオフセット防止液供給口との上流側に位置し、記録材への画像形成動作時に離間し、記録材への画像形成動作時に前記塗布ローラが回転する方向とは逆の回転に対してはカウンタ状態となるように構成されている。ここで、図２中、７はクリーニング部材６の離間量制御部、８はクリーニング部材環動作用摺動部、９は汚損物を示す。
【００１３】
更に、各ローラ１，２，３は、記録材への画像形成動作が終了した後、塗布ローラ３のオフセット防止液供給口５に位置する個所がクリーニング部材６を設けた位置を通過する回転量以上、画像形成動作時の各回転方向と逆の回転方向に回転するよう構成されている。
【００１４】
更に又、各ローラ１，２，３は、記録材への画像形成動作が終了した後、前記画像形成動作時の各回転方向と逆の回転方向に、前記各回転動作を行い、その後、前記画像形成動作時の前記各回転方向に、前記逆転時の回転量以上、回転するよう構成されてもよい。
【００１５】
このような画像形成装置を用いた際には、オフセット防止液供給位置に付着堆積した汚損物９が、塗布ローラ３に伝わり逆戻りする。この時、記録材への画像形成動作時に離間していたクリーニング部材６は逆回転に対してはカウンタ状態となり確実に加熱ローラ１に達する前にクリーニング部材６により移動してきた汚損物を掻き落としクリーニングする。その後、画像形成動作時と同じ方向に回転し、逆回転時に発生した各ローラ１，２，３上のオフセット防止液塗布ムラ状態を均一化することにより、次に行われる記録材への画像形成動作において出力画像のオフセット防止液塗布ムラを防止する。
【００１６】
【発明の効果】
以上説明したように、本発明の実施の形態によれば、記録材への画像形成動作が終了した後、前記画像形成動作時の前記各ローラ回転方向と逆の回転方向に、前記各ローラが回転するので、記録材への画像形成時に汚損物が前記各ローラを伝わり、オフセット防止液供給位置に付着堆積した汚損物を移動及び減少させることができる。
【００１７】
本発明の実施の形態によれば、記録材への画像形成動作時に離間し、記録材への画像形成動作時に前記塗布ローラが回転する方向とは逆の回転に対してはカウンタ状態となるように、クリーニング部材を、無端状帯体と塗布ローラ接触部より下流側でかつ、塗布ローラとオフセット防止液供給口との接触部より上流側の塗布ローラに設けるので、クリーニング部材の接触による塗布ローラのダメージを最小限にでき、且つオフセット防止液供給位置に付着堆積して塗布ローラの逆転により移動する汚損物を、確実に無端状帯体に達する前にクリーニング部材が設けられた個所へ通すことができる。
【００１８】
本発明の実施の形態によれば、記録材への画像形成動作が終了した後、前記塗布ローラのオフセット防止液供給口に位置する個所がクリーニング部材を設けた位置を通過する回転量以上、前記画像形成動作時の前記各ローラ回転方向と逆の回転方向に、前記各ローラを回転させるので、オフセット防止液供給位置に付着堆積した汚損物を、確実にクリーニング部材まで移動し、クリーニングすることができる。
【００１９】
本発明の実施の形態によれば、記録材への画像形成動作が終了した後、前記画像形成動作時の前記各ローラ回転方向と逆の回転方向に、前記各ローラの回転動作を行い、その後、前記画像形成動作時の前記各ローラ回転方向に、前記逆転時の回転量以上、前記各ローラが回転する動作を設けるので、前記画像形成動作時の前記各ローラ回転方向と逆の回転により発生した各ローラ上のオフセット防止液塗布ムラ状態を均一化し、次に行われる記録材への画像形成動作において、オフセット防止液の塗布ムラを防止することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態の画像形成装置を示す概略図ある。
【図２】塗布ローラを詳細に示す拡大図である。
【符号の説明】
１加熱ローラ（無端状帯体）
２加圧ローラ
３塗布ローラ
５オフセット防止液供給口
６クリーニング部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information output terminal device, and more particularly to an image forming apparatus such as a printer, a copying machine, and a facsimile.
[0002]
[Prior art]
As a prior art of the present invention, there is a fixing device including an endless belt heating roller and a pressure roller pressed against the heating roller. In such a fixing device, the heating roller or the pressure roller is separated. When the moldability is poor, some toner may adhere to the fixing roller or the pressure roller and offset may occur. It is known that a mold layer is formed and an application roller for applying an anti-offset liquid to the mold release layer is provided.
[0003]
[Problems to be solved by the invention]
However, since it is difficult to completely prevent the occurrence of offset in the above-described prior art, a small amount of offset remains on the heating roller or the pressure roller, and the offset preventing liquid that contacts the surface of the coating roller or the coating roller. The supply part is soiled with toner or paper powder. As a result, the amount of coating applied by the coating roller decreases and the surface is soiled depending on the use over time, so that the coating roller is reversely transferred to the heating roller and pressure roller. As a result, there is a problem of causing image smearing on the recording paper.
[0004]
Also, in recent years, paper that adheres and accumulates on the application roller for supplying the anti-offset liquid and the anti-offset liquid supply port due to the influence of the filler (filler) used to recycle the paper and improve the whiteness of the paper. The increase in the amount of powder is conspicuous, and if this paper dust increases, the adhesiveness of the toner causes stains that cannot be collected by the cleaning roller to remain on the surface of the application roller, resulting in a decrease in performance of the application roller. There is a problem in that the image quality is degraded.
[0005]
Therefore, the present invention was made to solve the above-described problems, without leaving paper dust on the surface of the coating roller and the offset prevention liquid supply portion, it is possible to prevent the performance deterioration of the coating roller, At the same time, it is an object of the present invention to provide an image forming apparatus that prevents a foreign matter from being reversely transferred from a coating roller to a heating roller and prevents deterioration in image quality.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, an image forming apparatus according to the present invention includes an endless belt provided with a heating element, a pressure roller pressed against the endless belt, the endless belt, The pressure roller includes at least an application roller that applies an anti-offset liquid to the endless belt, and passes a recording material on which a toner image is formed between the endless belt and the pressure roller. In an image forming apparatus for forming an image on the recording material by using a fixing device that fixes the toner image on the paper, the coating roller rotates when the image is formed on the recording material. From the contact portion between the endless belt and the application roller and the contact portion between the application roller and the offset prevention liquid supply port so as to be in a counter state with respect to the rotation opposite to the rotation direction. Provided upstream, the clip The ning member is separated from the application roller when the image is formed on the recording material, and after the image forming operation on the recording material is finished, the rotation direction is opposite to the rotation direction of each roller during the image forming operation. to, by Rukoto rotates the respective rollers, and characterized in that the cleaning member into contact with the coating roller.
[0007]
In the image forming apparatus of the present invention, the cleaning member may be in contact with the application roller in conjunction with the reverse rotation of the application roller during the image forming operation.
[0008]
In the image forming apparatus of the present invention, the after image forming operation on the recording material is completed, the rotation amount or more passing through a position where the point is located in the offset preventing liquid supply port of the application roller is provided with the cleaning member The rollers may be configured to rotate in a direction opposite to the direction of rotation of the rollers during the image forming operation.
[0009]
Further, in the image forming apparatus of the present invention, after the image forming operation on the recording material is finished, the rollers are rotated in the direction opposite to the roller rotating direction during the image forming operation. Thereafter, an operation may be provided in which the rollers rotate in the rotation direction of the rollers during the image forming operation by an amount greater than or equal to the rotation amount during the reverse rotation.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view showing an image forming apparatus according to an embodiment of the present invention, and FIG. 2 is an enlarged view showing a coating roller in detail.
[0011]
1 and 2, the image forming apparatus includes an endless belt-shaped heating roller 1 having a heating element, a pressure roller 2 pressed against the heating roller 1, and the heating roller 1 or the pressure roller 2. Among these, at least a heating roller 1 and an application roller 3 for applying an offset preventing liquid are provided, and a recording material on which a toner image is formed is passed between the heating roller 1 and the pressure roller 2 so as to pass the paper. The image forming apparatus is configured to form an image on a recording material by using a fixing device that fixes a toner image on the recording material. It is comprised so that it may rotate in the rotation direction opposite to the rotation direction.
[0012]
The side surface of the application roller 3 is provided with an offset prevention liquid supply port 5 for supplying the offset prevention liquid 4 and a cleaning member 6, and the cleaning member 6 is downstream of the contact portion between the heating roller 1 and the application roller 3. And at the upstream side of the application roller 3 and the offset prevention liquid supply port, are separated during the image forming operation on the recording material, and are opposite to the direction in which the application roller rotates during the image forming operation on the recording material. Is configured to be in a counter state. Here, in FIG. 2, 7 indicates a separation amount control unit for the cleaning member 6, 8 indicates a cleaning member ring operation sliding unit, and 9 indicates a contaminated material.
[0013]
Further, after the image forming operation on the recording material is completed, each of the rollers 1, 2, and 3 is rotated by a position where the position at the offset prevention liquid supply port 5 of the application roller 3 passes the position where the cleaning member 6 is provided. As described above, it is configured to rotate in the rotation direction opposite to each rotation direction during the image forming operation.
[0014]
Further, after the image forming operation on the recording material is finished, each of the rollers 1, 2, and 3 performs the rotation operation in the rotation direction opposite to the rotation direction at the time of the image formation operation, and then The image forming apparatus may be configured to rotate in the respective rotation directions during the image forming operation by an amount greater than or equal to the rotation amount during the reverse rotation.
[0015]
When such an image forming apparatus is used, the contaminated material 9 adhered and deposited at the offset prevention liquid supply position is transferred to the application roller 3 and returned. At this time, the cleaning member 6 that has been separated at the time of the image forming operation on the recording material is in a counter state with respect to the reverse rotation, and the dirt moved by the cleaning member 6 is scraped off before the heating roller 1 is reliably reached. To do. Thereafter, the image is rotated in the same direction as in the image forming operation, and the non-uniformity of the application of the anti-offset liquid on each of the rollers 1, 2, 3 generated at the time of reverse rotation is made uniform, so that the next image formation on the recording material In operation, unevenness in the application of the anti-offset liquid to the output image is prevented.
[0016]
【The invention's effect】
As described above, according to the embodiment of the present invention, after the image forming operation on the recording material is finished, the rollers are rotated in the rotation direction opposite to the roller rotation direction during the image forming operation. Since it rotates, the contaminants are transferred to the rollers during image formation on the recording material, and the contaminants deposited and deposited at the offset prevention liquid supply position can be moved and reduced.
[0017]
According to the embodiment of the present invention, it is separated at the time of the image forming operation on the recording material, and is in the counter state with respect to the rotation opposite to the direction in which the application roller rotates at the time of the image forming operation on the recording material. In addition, the cleaning member is provided on the application roller at the downstream side from the contact portion between the endless belt and the application roller contact portion and at the upstream side from the contact portion between the application roller and the offset prevention liquid supply port. The dirt that adheres and accumulates at the offset prevention liquid supply position and moves by the reverse rotation of the application roller is surely passed through the place where the cleaning member is provided before reaching the endless belt. Can do.
[0018]
According to the embodiment of the present invention, after the image forming operation on the recording material is completed, the position located at the offset prevention liquid supply port of the application roller is equal to or more than the rotation amount passing the position where the cleaning member is provided. Since each roller is rotated in a rotation direction opposite to the rotation direction of each roller during the image forming operation, it is possible to reliably move the contaminants deposited and deposited on the offset prevention liquid supply position to the cleaning member and clean them. it can.
[0019]
According to the embodiment of the present invention, after the image forming operation on the recording material is finished, the rotation operation of each roller is performed in the rotation direction opposite to the rotation direction of each roller during the image formation operation, and then The roller rotation direction at the time of the image forming operation is provided with an operation for rotating the rollers at a rotation amount equal to or greater than the rotation amount at the time of the reverse rotation, so that the rotation occurs in the direction opposite to the roller rotation direction at the time of the image forming operation. Thus, the uneven application state of the offset preventing liquid on each roller can be made uniform, and the uneven application of the offset preventing liquid can be prevented in the next image forming operation on the recording material.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating an image forming apparatus according to an embodiment of the present invention.
FIG. 2 is an enlarged view showing the application roller in detail.
[Explanation of symbols]
1 Heating roller (endless belt)
2 Pressure roller 3 Application roller 5 Offset prevention liquid supply port 6 Cleaning member

Claims

An endless belt provided with a heating element, a pressure roller pressed against the endless belt, and the endless belt or an offset preventing liquid in at least the endless belt of the pressure roller Using a fixing device that passes a recording material on which a toner image is formed between the endless belt and the pressure roller and fixes the toner image on the paper. In the image forming apparatus for forming an image on the recording material,
Contact between the endless strip and the application roller so that the cleaning member of the application roller is in a counter state with respect to rotation opposite to the direction in which the application roller rotates during image formation on the recording material. Provided on the downstream side of the portion and upstream of the contact portion between the application roller and the offset prevention liquid supply port,
The cleaning member is separated from the application roller during image formation on the recording material,
Wherein after the image forming operation on the recording material is completed, the rotational direction of the roller rotation direction opposite to the time of the image forming operation, the by Rukoto rotate the respective rollers, the cleaning member and the applying roller and those An image forming apparatus that is in contact with each other.

The image forming apparatus according to claim 1, wherein the cleaning member is in contact with the application roller in conjunction with a rotation opposite to that during the image forming operation of the application roller.

After the image forming operation on the recording material is finished, each roller at the time of the image forming operation is equal to or more than the rotation amount at which the position located at the offset prevention liquid supply port of the coating roller passes the position where the cleaning member is provided. 3. The image forming apparatus according to claim 1, wherein each of the rollers is rotated in a rotation direction opposite to the rotation direction.

After the image forming operation on the recording material is completed, the rollers are rotated in the direction opposite to the rotation direction of the rollers at the time of the image forming operation, and then each of the rollers at the time of the image forming operation is performed. 4. The image forming apparatus according to claim 1, wherein an operation of rotating each of the rollers is provided in a roller rotation direction by an amount greater than or equal to a rotation amount during the reverse rotation.