JPH07234604A - Image forming device - Google Patents
Image forming deviceInfo
- Publication number
- JPH07234604A JPH07234604A JP6049873A JP4987394A JPH07234604A JP H07234604 A JPH07234604 A JP H07234604A JP 6049873 A JP6049873 A JP 6049873A JP 4987394 A JP4987394 A JP 4987394A JP H07234604 A JPH07234604 A JP H07234604A
- Authority
- JP
- Japan
- Prior art keywords
- unit
- loop
- recording medium
- fixing
- speed
- 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
Landscapes
- Fixing For Electrophotography (AREA)
- Control Or Security For Electrophotography (AREA)
- Controlling Sheets Or Webs (AREA)
Abstract
Description
【発明の詳細な説明】Detailed Description of the Invention
【０００１】[0001]
【産業上の利用分野】本発明は電子写真方式の画像形成
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 electrophotographic image forming apparatus.
【０００２】[0002]
【従来の技術】従来この種の装置としては、図１４にそ
の内部構造の例が示されるような画像形成装置がある。2. Description of the Related Art Conventionally, as an apparatus of this type, there is an image forming apparatus whose internal structure is shown in FIG.
【０００３】すなわち、この画像形成装置にあっては、
給紙部５０１から給紙された用紙５０２は、転写ユニッ
ト５０３の外周にグリッパ５０３ｆでその用紙の先端を
把持され、さらに静電吸着方法や空気による吸引方法に
より保持される。光学ユニット５０７による潜像はドラ
ム・クリーナユニットＣ’の像担持体１’上に形成され
る、現像カートリッジにより現像像化された現像像は順
次、転写ユニット５０３上の用紙５０２に転写され、画
像が形成された後、転写ユニット５０３より分離爪５１
１により分離されて、定着ユニット５０４により、定着
され、排紙部５０５から排紙トレー部５０６に排出され
る。That is, in this image forming apparatus,
The paper 502 fed from the paper feeding unit 501 is held on the outer periphery of the transfer unit 503 by the gripper 503f at the front end of the paper, and is further held by an electrostatic adsorption method or an air suction method. The latent image formed by the optical unit 507 is formed on the image carrier 1 ′ of the drum cleaner unit C ′, and the developed images developed by the developing cartridge are sequentially transferred to the paper 502 on the transfer unit 503, and the image is formed. After the transfer unit 503 is formed, the separation claw 51 is formed.
The sheet is separated by 1, fixed by the fixing unit 504, and discharged from the sheet discharge unit 505 to the sheet discharge tray unit 506.
【０００４】ところで、この種の画像形成装置におい
て、転写ユニット５０３と定着ユニット５０４の速度は
用紙５０４を両ユニット間で等速度で搬送するために設
計上固定されていた。By the way, in this type of image forming apparatus, the transfer unit 503 and the fixing unit 504 are designed to have a fixed speed in order to convey the paper 504 at a constant speed between the two units.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、このよ
うな従来例において、定着ユニット５０４のドラムのニ
ップ量の変化に伴って定着ユニット５０４の搬送速度は
変化し、そのため転写ユニット５０３の搬送速度と前記
定着ユニット５０４の間に速度差が生じ、転写ユニット
５０３を通過している用紙に外力が加わる。この外力が
転写ユニット５０３の速度変化の要因となり、生じた速
度変化は画像のピッチ不良の原因となる。本発明は、上
記従来技術の問題を解決するためになされたもので、そ
の目的とするところは、このような定着手段のニップ量
の変化に伴う転写手段の搬送速度変化を、定着手段また
は転写手段の駆動手段の速度を制御することによって一
定に保ち、転写手段にある用紙に外力がかかるのを防
ぎ、ピッチ不良の発生を減少できる画像形成装置を提供
することにある。However, in such a conventional example, the conveyance speed of the fixing unit 504 changes with the change of the nip amount of the drum of the fixing unit 504, and therefore the conveyance speed of the transfer unit 503 and the above-mentioned conveyance speed. A speed difference occurs between the fixing units 504, and an external force is applied to the sheet passing through the transfer unit 503. This external force causes a speed change of the transfer unit 503, and the generated speed change causes a pitch defect of the image. The present invention has been made in order to solve the above-mentioned problems of the prior art, and an object of the present invention is to reduce the change in the conveyance speed of the transfer unit due to the change in the nip amount of the fixing unit. It is an object of the present invention to provide an image forming apparatus capable of keeping a constant speed by controlling the speed of the driving means of the means, preventing an external force from being applied to the paper on the transfer means, and reducing the occurrence of pitch defects.
【０００６】[0006]
【課題を解決するための手段】上記目的を達成するため
に本発明にあっては、定着手段と転写手段に独立した駆
動系を設け、分離爪により転写手段から分離された記録
媒体の、その転写手段からの分離部と定着手段の入口手
前部の間でループを形成させ、この形成されたループ量
を検出するループ検出手段を設け、前記検出ループ量に
基づいて定着手段の駆動手段の速度を制御した。 ま
た、前記ループ検出手段において、記録媒体の形成する
ループ量の上限と下限を検知するセンサを設け、前記ル
ープ量の上限を検知したとき定着手段の駆動手段の速度
を速くし、また、前記ループ量の下限を検知したとき定
着手段の駆動手段の速度を遅くするように制御を行って
もよく、その場合に一個のセンサを用いて記録媒体の形
成するループ量の上限と下限を検知してもよい。In order to achieve the above object, according to the present invention, a fixing medium and a transfer means are provided with independent drive systems, and a recording medium separated from the transfer means by a separation claw is provided. A loop is formed between the separating part from the transfer means and the front part of the entrance of the fixing means, and a loop detecting means for detecting the amount of the formed loop is provided, and the speed of the driving means of the fixing means based on the detected loop quantity. Controlled. Further, the loop detecting means is provided with a sensor for detecting an upper limit and a lower limit of the loop amount formed by the recording medium, and when the upper limit of the loop amount is detected, the speed of the driving means of the fixing means is increased, and the loop When the lower limit of the amount is detected, control may be performed so as to slow down the speed of the driving unit of the fixing unit, and in that case, one sensor is used to detect the upper limit and the lower limit of the loop amount formed by the recording medium. Good.
【０００７】また、前記ループ検出手段を転写手段の記
録媒体分離検知手段として兼用してもよい。さらに、前
記ループ検出手段において、記録媒体に接し、該記録媒
体のループ量に応じて変移する部材を設け、該部材の変
移量を検出し、該検出変移量を一定に保つように、定着
手段の駆動手段の速度制御を行っても良い。The loop detecting means may also be used as the recording medium separation detecting means of the transfer means. Further, the loop detecting means is provided with a member that is in contact with the recording medium and that changes in accordance with the loop amount of the recording medium, detects the amount of change of the member, and fixes the fixing amount so as to keep the detected amount of change constant. The speed of the driving means may be controlled.
【０００８】転写手段の分離部付近に記録媒体を上方に
ループさせ、かつ、記録媒体のループ量に応じて、揺動
可能なレバー部材を設け、該レバー部材の変移角度を検
出し、該角度を一定に保つように定着手段の駆動手段の
速度制御を行ってもよい。The recording medium is looped upward in the vicinity of the separating portion of the transfer means, and a swingable lever member is provided according to the loop amount of the recording medium. The displacement angle of the lever member is detected, and the angle is detected. The speed of the driving means of the fixing means may be controlled so as to keep constant.
【０００９】転写手段より分離された記録媒体を転写手
段と定着手段間の搬送経路直線上より自重方向にガイド
する手段を設け、転写手段と定着手段間での記録媒体の
ループを下側に形成し、前記ガイド手段と記録媒体間の
ギャップ量を検出する手段を設け、該検出ギャップ量に
基づいて定着手段の駆動手段の速度制御を行ってもよ
く、またこの構成において、転写手段の分離部分付近に
転写手段と定着手段の搬送経路直線上の記録媒体との角
度を検出する手段を設け、該角度を一定に保つように定
着手段の駆動手段の速度制御を行ってもよい。 上記の
構成において、定着手段ではなく転写手段の駆動手段の
速度制御を行ってもよい。A means for guiding the recording medium separated by the transfer means in the self-weight direction from the straight line of the conveying path between the transfer means and the fixing means is provided, and a loop of the recording medium between the transfer means and the fixing means is formed on the lower side. However, a means for detecting the gap amount between the guide means and the recording medium may be provided, and the speed of the driving means for the fixing means may be controlled based on the detected gap amount. A means for detecting the angle between the transfer means and the recording medium on the straight line of the conveyance path of the fixing means may be provided, and the speed of the driving means of the fixing means may be controlled so as to keep the angle constant. In the above configuration, the speed control of the driving unit of the transfer unit may be performed instead of the fixing unit.
【００１０】[0010]
【作用】上記のように構成された画像形成装置では、そ
の転写手段から分離された記録媒体は定着手段へと搬送
され、この搬送速度は、定着手段のドラムのニップ量の
変化に伴って速度変化する。この際に、転写手段と定着
手段の間に形成される用紙のループ量が定着手段の入口
手前部で検出され、前記検出ループ量に基づいて定着手
段または転写手段の駆動手段の速度制御が行われる。こ
れにより、転写手段にある記録媒体に外力がかかるのを
防ぎ、転写手段の搬送速度を一定に保ち、ピッチ不良の
発生を減少させる事ができる。In the image forming apparatus constructed as described above, the recording medium separated from the transfer means is conveyed to the fixing means, and the conveying speed is the speed as the nip amount of the drum of the fixing means changes. Change. At this time, the loop amount of the sheet formed between the transfer unit and the fixing unit is detected in the front part of the entrance of the fixing unit, and the speed control of the fixing unit or the transfer unit driving unit is performed based on the detected loop amount. Be seen. As a result, it is possible to prevent an external force from being applied to the recording medium in the transfer means, keep the transfer speed of the transfer means constant, and reduce the occurrence of pitch defects.
【００１１】[0011]
【実施例】以下に本発明を図示の実施例に基づいて説明
する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments.
【００１２】（第１実施例）図１は本発明の第１実施例
を表すの画像形成装置としての電子写真方式の画像形成
装置の全体構成図である。図１において、１０１は画像
形成媒体である用紙を補給する給紙部、１０２は記録媒
体としての用紙、１０３は転写手段としての独立した駆
動手段を持ち転写ドラム１０３ｄを有する転写ユニッ
ト、１０３ｆは用紙を転写ドラム上に保持する際にその
用紙の先端を把持するグリッパ、Ｃはドラムクリーナユ
ニット、１は像担持体、１０４は定着手段としての独立
した駆動手段を持ち画像を定着させる定着ユニット、１
０４ｒは定着ローラ、１１１は転写ドラム１０３ｄから
用紙を分離するための分離手段としての分離爪、１０５
は用紙を排紙する排紙部、１０６は用紙の排紙トレー
部、１０７は光学ユニット、１０８は現像カートリッジ
保持部材、１１０は現像カートリッジ保持部材１０８の
軸である。(First Embodiment) FIG. 1 is an overall configuration diagram of an electrophotographic image forming apparatus as an image forming apparatus according to a first embodiment of the present invention. In FIG. 1, 101 is a paper feed unit for replenishing paper as an image forming medium, 102 is paper as a recording medium, 103 is a transfer unit having an independent driving means as transfer means and a transfer drum 103d, and 103f is paper. , A gripper for holding the leading edge of the sheet when the sheet is held on the transfer drum, C is a drum cleaner unit, 1 is an image carrier, 104 is a fixing unit for fixing an image by having an independent driving unit as a fixing unit, 1
Reference numeral 04r is a fixing roller, 111 is a separation claw as separation means for separating the paper from the transfer drum 103d, and 105
Is a paper ejection unit for ejecting paper, 106 is a paper ejection tray unit, 107 is an optical unit, 108 is a developing cartridge holding member, and 110 is a shaft of the developing cartridge holding member 108.
【００１３】図２は転写ユニット１０３と定着ユニット
１０４周辺要部拡大図であり、２００は用紙１０２のル
ープ量を検出するループ検出手段としてのセンサフラ
グ、２００ａ，２００ｂはセンサフラグ２００に作用す
るセンサ、２００ｃはセンサフラグの軸、２００ｄはセ
ンサフラグ２００の上側ストッパである。FIG. 2 is an enlarged view of a main part around the transfer unit 103 and the fixing unit 104. Reference numeral 200 is a sensor flag as a loop detecting means for detecting the loop amount of the paper 102, and 200a and 200b are sensors acting on the sensor flag 200. , 200c is a sensor flag axis, and 200d is an upper stopper of the sensor flag 200.
【００１４】図１において、給紙部１０１から給紙され
た用紙１０２は、その先端を転写ドラム１０３ｄのグリ
ッパ１０３ｆにより把持されて、転写ユニット１０３の
転写ドラム１０３ｄ外周上に静電吸着方法や空気による
吸引方法により保持される。光学ユニット１０７により
各色毎の潜像がドラムクリーナユニットＣの像担持体１
上に形成される。現像器選択機構は像担持体１の軸に平
行な軸１１０を回転中心として回転可能な現像カートリ
ッジ保持部材１０８と、現像カートリッジ保持部材１０
８を回動して現像カートリッジを選択移動するための制
御・駆動機構、および、各現像カートリッジを特定の姿
勢に維持するための駆動機構等により構成される。上記
選択機構により各色毎に現像像化された現像像は順次、
転写ユニット１０３の転写ドラム上１０３ｄの用紙１０
２に転写され、多色画像が形成された後、転写ドラム１
０３ｄより分離手段としての分離爪１１１により分離さ
れ、その後定着ユニット１０４により定着され、排紙部
１０５から排紙トレー部１０６に排出される。In FIG. 1, the paper 102 fed from the paper feed unit 101 has its front end gripped by the gripper 103f of the transfer drum 103d, and the electrostatic adsorption method or air is applied to the outer periphery of the transfer drum 103d of the transfer unit 103. It is held by the suction method. The image bearing member 1 of the drum cleaner unit C produces a latent image for each color by the optical unit 107.
Formed on. The developing device selection mechanism includes a developing cartridge holding member 108 and a developing cartridge holding member 10 which are rotatable about an axis 110 parallel to the axis of the image carrier 1 as a rotation center.
It is composed of a control / driving mechanism for rotating 8 to selectively move the developing cartridges, a driving mechanism for maintaining each developing cartridge in a specific posture, and the like. The developed image for each color by the above selection mechanism is sequentially developed,
Paper 10 on transfer drum 103d of transfer unit 103
2 and the multicolor image is formed, the transfer drum 1
The sheet is separated from the sheet 03d by a separating claw 111 as a separating unit, is then fixed by the fixing unit 104, and is discharged from the sheet discharge unit 105 to the sheet discharge tray unit 106.
【００１５】ここで、転写ユニット１０３の転写ドラム
１０３ｄより分離爪１１１により分離された用紙１０２
は図２，３に示すように、その先端が転写ユニット１０
３から定着ユニット１０４の搬送経路間に設置されてい
るセンサフラグ２００に作用してセンサ２００ａをＯＮ
にする。前記センサ２００ａがＯＮされると用紙１０２
が転写ユニット１０３から分離されたことを検知し、同
時にタイマをスタートさせる。センサフラグ２００が分
離検知してから前記用紙１０２が定着ユニット１０４に
突き当たるまで、すなわち該定着ユニット１０４によっ
て駆動開始されるまでの時間ｔ０中は、定着ユニット１
０４の駆動手段としての駆動系の搬送速度を初期設定速
度で駆動させる。用紙１０２が定着ユニット１０４によ
り駆動開始されるとその駆動手段としての駆動系の搬送
速度を初期設定速度は定着ユニットの駆動系の搬送速度
より遅く設定されており、分離爪１１１の先端に形成さ
れる分離部と定着ユニット１０４にある定着ローラ１０
４ｒのニップとの間でループを形成させる。その後次の
ようにある一定の時間間隔で速度の制御を行う。センサ
２００ｂがＯＮされると用紙１０２の形成するループが
大きくなっているので定着ユニット１０４の駆動手段と
しての駆動系の搬送速度をある一定量速くする。センサ
２００ａがＯＮされると用紙１０２の形成するループが
小さくなっているので、定着ユニット１０４の駆動手段
としての駆動系の搬送速度をある一定量遅くする。セン
サ２００ａ及びセンサ２００ｂが共にＯＦＦのとき用紙
１０２の形成するループは一定に保たれているので速度
調整を行わない。Here, the sheet 102 separated by the separation claw 111 from the transfer drum 103d of the transfer unit 103.
As shown in FIGS. 2 and 3, the tip of the transfer unit 10
3 acts on the sensor flag 200 installed between the conveyance paths of the fixing unit 104 to turn on the sensor 200a.
To When the sensor 200a is turned on, the paper 102
Is detected from the transfer unit 103, and at the same time, the timer is started. During the time t0 from when the sensor flag 200 separates and detects the sheet 102 to hit the fixing unit 104, that is, before the driving by the fixing unit 104 is started, the fixing unit 1
The transport speed of the drive system as the drive means of No. 04 is driven at the initial set speed. When the sheet 102 is started to be driven by the fixing unit 104, the transport speed of the drive system as the drive unit is set to an initial setting speed lower than the transport speed of the drive system of the fixing unit, and the sheet is formed at the tip of the separation claw 111. And the fixing roller 10 in the fixing unit 104.
A loop is formed between the nip of 4r. After that, the speed is controlled at a constant time interval as follows. When the sensor 200b is turned on, the loop formed by the sheet 102 becomes large, and therefore the transport speed of the drive system as the drive unit of the fixing unit 104 is increased by a certain amount. When the sensor 200a is turned on, the loop formed by the sheet 102 is small, so the transport speed of the drive system as the drive unit of the fixing unit 104 is reduced by a certain amount. When both the sensor 200a and the sensor 200b are OFF, the loop formed by the paper 102 is kept constant, and therefore speed adjustment is not performed.
【００１６】以上の速度調整は用紙１０２が転写ドラム
１０３ｄから完全に分離されるまでに要する時間ｔ１中
行う。その後用紙１０２が完全に定着されるまで速度調
整は行わない。図４に、前述の駆動手段としての駆動系
の搬送速度の制御系フローチャートを示す。The above speed adjustment is performed during the time t1 required for the paper 102 to be completely separated from the transfer drum 103d. After that, speed adjustment is not performed until the paper 102 is completely fixed. FIG. 4 shows a control system flowchart of the transport speed of the drive system as the above-mentioned drive means.
【００１７】また、ループ量の上限と下限の検知に図
５，６に示すように１個のセンサを用いてもよい。ルー
プ検出手段としてのセンサフラグ２１０は用紙のループ
量が下限領域にある時センサ２１０ａをＯＮに保ち、上
限領域にあるときセンサ２１０ａをＯＦＦに保つ。用紙
１０２がセンサフラグ２１０に作用するとセンサ２１０
ａはＯＮになり、転写分離検知し、同時にタイマをスタ
ートする。この場合、センサ２１０ａはループ検出手段
と転写ドラム１０３ｄの用紙分離検知手段とを兼用して
いる。Further, one sensor may be used for detecting the upper limit and the lower limit of the loop amount as shown in FIGS. The sensor flag 210 as a loop detecting means keeps the sensor 210a ON when the loop amount of the paper is in the lower limit region, and keeps the sensor 210a OFF when it is in the upper limit region. When the sheet 102 acts on the sensor flag 210, the sensor 210
a is turned on, the transfer separation is detected, and the timer is started at the same time. In this case, the sensor 210a also serves as the loop detection means and the sheet separation detection means of the transfer drum 103d.
【００１８】タイマがｔ０以下の時、すなわち、用紙１
０２が定着ユニットに駆動開始されるまで速度調整は行
わない。速度調整を行うとき、ある一定間隔でフラグ２
１０ａの状態を検知し、センサ２１０ａがＯＮの時定着
ユニット１０４の駆動手段としての駆動系の搬送速度を
ある一定量遅くする。また、センサ２１０ａがＯＦＦの
時定着ユニット１０４の駆動手段としての駆動系の搬送
速度をある一定量速くする。速度調整は時間ｔ１以下の
とき、すなわち用紙１０２が転写ドラム１０３ｄから完
全に分離されるまで続ける。その後用紙１０２が定着終
了されるまで再度調整は行わない。図１３に当実施例に
て採用できるブロック図を示す。When the timer is t0 or less, that is, the paper 1
The speed is not adjusted until 02 is driven by the fixing unit. When adjusting the speed, flag 2 at certain intervals
The state of 10a is detected, and when the sensor 210a is ON, the conveying speed of the drive system as the drive unit of the fixing unit 104 is reduced by a certain amount. Further, when the sensor 210a is OFF, the transport speed of the drive system as the drive unit of the fixing unit 104 is increased by a certain amount. The speed adjustment is continued at time t1 or less, that is, until the sheet 102 is completely separated from the transfer drum 103d. After that, the adjustment is not performed again until the sheet 102 is fixed. FIG. 13 shows a block diagram that can be adopted in this embodiment.
【００１９】（第２実施例）図７，８に本発明の第２実
施例を表す転写ユニット１０３と定着ユニット１０４周
辺の要部拡大図である。(Second Embodiment) FIGS. 7 and 8 are enlarged views of a main part around a transfer unit 103 and a fixing unit 104 showing a second embodiment of the present invention.
【００２０】図７，８に示す構成はループ検出手段とし
てセンサフラグ２２０、変動量検出器２２０ａ、センサ
フラグのストッパ２２０ｂとセンサフラグ２２０の回転
軸２２０ｃによって構成される。The configuration shown in FIGS. 7 and 8 is composed of a sensor flag 220, a fluctuation amount detector 220a, a sensor flag stopper 220b, and a rotary shaft 220c of the sensor flag 220 as loop detection means.
【００２１】図７において、用紙１０２が転写ユニット
１０３から分離されて定着ユニット１０４に搬送される
間前記用紙１０２はセンサフラグ２２０に作用する。前
記センサフラグ２２０は回転軸２２０ｃを中心に回転
し、変動量検出器２２０ａを回転する。変動量検出器２
２０ａがフラグの移動を検知すると用紙１０２の転写ド
ラム１０３ｄからの分離を検知し、タイマをスタートす
る。時間ｔ０以下の間、すなわち用紙１０２が定着ユニ
ット１０４によって駆動開始されるまでは、速度制御を
行わない。In FIG. 7, the sheet 102 acts on the sensor flag 220 while the sheet 102 is separated from the transfer unit 103 and conveyed to the fixing unit 104. The sensor flag 220 rotates about a rotation shaft 220c and rotates a fluctuation amount detector 220a. Fluctuation detector 2
When 20a detects the movement of the flag, the separation of the sheet 102 from the transfer drum 103d is detected, and the timer is started. During the time t0 or less, that is, until the sheet 102 is driven by the fixing unit 104, the speed control is not performed.
【００２２】図９は、当実施例の制御ブロック線図であ
る。FIG. 9 is a control block diagram of this embodiment.
【００２３】変動量検出器２２０ａは信号３０２を発生
する。該信号３０２を目標信号３０３と比較して、該比
較信号を制御器３０１の入力とする。制御器３０１の出
力信号３０４に定着ユニット１０４の初期設定回転速度
信号３０５を付加して、新定着ユニット駆動速度３０１
を得る。速度制御は時間ｔ１以下のとき、すなわち用紙
１０２が転写ドラム１０３ｄから完全に分離されるまで
行う。その後用紙１０２が定着終了するまで定着ユニッ
ト１０４の速度制御は行わない。The variation detector 220a produces a signal 302. The signal 302 is compared with the target signal 303, and the comparison signal is input to the controller 301. The initial setting rotation speed signal 305 of the fixing unit 104 is added to the output signal 304 of the controller 301, and the new fixing unit drive speed 301
To get The speed control is performed when the time t1 or less, that is, until the sheet 102 is completely separated from the transfer drum 103d. After that, the speed control of the fixing unit 104 is not performed until the fixing of the sheet 102 is completed.
【００２４】（第３実施例）図１０は本発明の第３実施
例を表す転写ユニット１０３と定着ユニット１０４周辺
の要部拡大図である。(Third Embodiment) FIG. 10 is an enlarged view of a main part around a transfer unit 103 and a fixing unit 104 showing a third embodiment of the present invention.
【００２５】図１０に示す構成はループ検出手段として
フラッパ２３０と角度検出器２３０ｃにより構成され
る。The configuration shown in FIG. 10 comprises a flapper 230 and an angle detector 230c as loop detecting means.
【００２６】用紙１０２は転写ドラム１０３ｄから分離
されてフラッパ２３０に作用する。用紙１０２はその自
重によって該フラッパ２３０を回転させる。この時フラ
ッパ２３０は角度検出器２３０ｃに作用し、同時にタイ
マをスタートする。用紙１０２は下側ループを形成した
後用紙ガイド２３１によって定着ユニット１０４に搬送
される。The sheet 102 is separated from the transfer drum 103d and acts on the flapper 230. The sheet 102 rotates the flapper 230 by its own weight. At this time, the flapper 230 acts on the angle detector 230c and simultaneously starts the timer. The sheet 102 is conveyed to the fixing unit 104 by the sheet guide 231 after forming the lower loop.
【００２７】この実施例における制御ブロック線図を図
１１に示す。角度測定器２３０ｃによって発生する信号
３３２と目標角度３３３を比較し、該比較結果を制御系
３３１の入力とする。該制御系の出力３３４に初期設定
定着器回転速度３３５を付加して新定着器回転速度３３
１を得る。速度調整は時間ｔ０以上ｔ１以下の時、すな
わち用紙１０２が定着ユニット１０４により駆動開始さ
れてから、転写ドラム１０３ｄから完全に分離される
間、のみ行う。上記の制御により、該角度は一定にな
る。A control block diagram in this embodiment is shown in FIG. The signal 332 generated by the angle measuring device 230c is compared with the target angle 333, and the comparison result is input to the control system 331. A new fixing device rotation speed 33 is obtained by adding an initial setting fixing device rotation speed 335 to the output 334 of the control system.
Get one. The speed adjustment is performed only when time t0 or more and time t1 or less, that is, while the sheet 102 is driven by the fixing unit 104 and completely separated from the transfer drum 103d. By the above control, the angle becomes constant.
【００２８】用紙１０２の形成するループが上側ループ
のときも前記制御方式が使用できる。しかし、そのと
き、フラッパ２３０は転写ユニット１０３から定着ユニ
ット１０４の搬送経路線上より上方向に角度設置され用
紙１０２は自重により定着ユニット１０４への搬送ガイ
ドに突き当たる。The above control method can be used even when the loop formed by the paper 102 is the upper loop. However, at that time, the flapper 230 is installed at an angle upward from the transfer path line of the transfer unit 103 to the fixing unit 104, and the sheet 102 abuts the transfer guide to the fixing unit 104 by its own weight.
【００２９】（第４実施例）図１２は本発明の第４実施
例を表す転写ユニット１０３と定着ユニット１０４周辺
の要部拡大図である。(Fourth Embodiment) FIG. 12 is an enlarged view of a main part around a transfer unit 103 and a fixing unit 104 showing a fourth embodiment of the present invention.
【００３０】用紙１０２が定着ユニット１０４によって
駆動開始される時にすでに現像が終了しているように定
着ユニット１０４と転写ユニット１０３の距離を設定
し、定着ユニット１０４の速度ではなく転写ユニット１
０３の駆動手段としての駆動系の搬送速度を制御して、
ループ量を一定に保つ。The distance between the fixing unit 104 and the transfer unit 103 is set so that the development is already completed when the sheet 102 is driven by the fixing unit 104, and the transfer unit 1 is set not the speed of the fixing unit 104.
By controlling the transport speed of the drive system as the drive means of 03,
Keep the loop amount constant.
【００３１】[0031]
【発明の効果】本発明は以上の構成および作用を有する
もので、画像形成装置の転写手段から分離された記録媒
体は定着手段へと搬送される。この搬送速度は、定着手
段としての定着ユニットの定着ローラのニップ量の変化
に伴って速度変化するが、この際に、転写手段と定着手
段の間に形成される記録媒体のループ量を定着手段入口
手前部で検出し、前記検出ループ量に基づいて定着手段
の駆動手段の速度制御を行うことにより、転写手段の搬
送速度を一定に保て、転写手段に外力がかかるのを防
ぎ、ピッチ不良の発生を減少させる事ができる。According to the present invention having the above-mentioned structure and operation, the recording medium separated from the transfer means of the image forming apparatus is conveyed to the fixing means. The transport speed changes with the change in the nip amount of the fixing roller of the fixing unit as the fixing unit. At this time, the loop amount of the recording medium formed between the transfer unit and the fixing unit is set to the fixing unit. The conveyance speed of the transfer means is kept constant by detecting the speed in front of the entrance and controlling the speed of the drive means of the fixing means based on the detection loop amount, preventing external force from being applied to the transfer means, and causing defective pitch. It is possible to reduce the occurrence of.
【００３２】前記ループ検出手段において、記録媒体の
形成するループ量の上限と下限を検知するセンサを設
け、前記ループ量の上限を検知したとき定着手段の駆動
系駆動源の速度を速くし、また、前記ループ量の下限を
検知したとき定着手段の駆動系駆動源の速度を遅くする
こともでき、この場合には比較的簡単な制御で目的を達
成できる。また、この場合に一個のセンサを用いて記録
媒体の形成するループ量の上限と下限を検知すればセン
サの個数削減によるコスト低減が図れる。The loop detecting means is provided with a sensor for detecting the upper limit and the lower limit of the loop amount formed by the recording medium, and when the upper limit of the loop amount is detected, the speed of the drive system drive source of the fixing means is increased, and When the lower limit of the loop amount is detected, the speed of the drive system drive source of the fixing unit can be slowed down. In this case, the object can be achieved by relatively simple control. Further, in this case, if one sensor is used to detect the upper limit and the lower limit of the loop amount formed by the recording medium, the cost can be reduced by reducing the number of sensors.
【００３３】同様に、前記ループ検出手段を転写ドラム
の記録媒体分離検知手段として兼用すればコスト低減が
図れる。さらに、前記ループ検出手段において、記録媒
体に接し、該記録媒体のループ量に応じて変移する部材
を設け、該部材の変移量を検出し、該検出変移量を一定
に保つように定着手段の駆動手段の速度制御を行うこと
により、より最適な搬送速度を得ることができる。Similarly, if the loop detecting means is also used as the recording medium separation detecting means of the transfer drum, the cost can be reduced. Further, the loop detecting means is provided with a member that is in contact with the recording medium and that changes in accordance with the loop amount of the recording medium, detects the amount of change of the member, and fixes the fixing means to keep the detected amount of change constant. By controlling the speed of the driving means, a more optimal transport speed can be obtained.
【００３４】転写手段の分離部付近に記録媒体を上方に
ループさせ、かつ、記録媒体のループ量に応じて、揺動
可能なレバー部材を設け、該レバー部材の変移角度を検
出し、該角度を一定に保つように定着手段の駆動手段の
速度制御を行うことでもより最適な搬送速度を得ること
ができる。転写手段より分離された記録媒体を転写手段
と定着手段間の搬送経路直線上より自重方向にガイドす
る手段を設け、転写手段と定着手段間での記録媒体のル
ープを下側に形成し、前記ガイド手段と記録媒体間のギ
ャップ量を検出する手段を設け、該検出ギャップ量に基
づいて定着手段の駆動手段の速度制御を行うことも可能
で、またこの構成において、転写手段の分離部分付近に
転写手段と定着手段の搬送経路直線上の記録媒体との角
度を検出する手段を設け、該角度を一定に保つように定
着手段の駆動手段の速度制御を行うことにより同様に最
適な搬送速度を得ることができる。上記の構成におい
て、定着手段ではなく転写手段の駆動手段の速度制御を
行うことによっても結果として、転写手段に外力がかか
るのを防ぎ、ピッチ不良の発生を減少させる事ができ
る。The recording medium is looped upward in the vicinity of the separating portion of the transfer means, and a swingable lever member is provided according to the loop amount of the recording medium, and the displacement angle of the lever member is detected, and the angle is detected. A more optimal conveying speed can be obtained by controlling the speed of the driving means of the fixing means so as to keep constant. A means for guiding the recording medium separated from the transfer means in the self-weight direction from the straight line of the conveying path between the transfer means and the fixing means is provided, and a loop of the recording medium between the transfer means and the fixing means is formed on the lower side, It is also possible to provide a means for detecting the gap amount between the guide means and the recording medium, and to control the speed of the driving means of the fixing means based on the detected gap amount. By providing a means for detecting the angle between the transfer means and the recording medium on the straight line of the conveying path of the fixing means and controlling the speed of the driving means of the fixing means so as to keep the angle constant, the optimum conveying speed is similarly obtained. Obtainable. In the above configuration, by controlling the speed of the driving unit of the transfer unit instead of the fixing unit, it is possible to prevent external force from being applied to the transfer unit and reduce the occurrence of pitch defects.
【図１】図１は本発明を実施した画像形成装置の側面図
である。FIG. 1 is a side view of an image forming apparatus embodying the present invention.
【図２】図２は図１の装置の要部拡大図である。FIG. 2 is an enlarged view of a main part of the apparatus shown in FIG.
【図３】図３は図２のセンサの動きを示す図である。FIG. 3 is a diagram showing the movement of the sensor of FIG.
【図４】図４は搬送速度の制御系フローチャートであ
る。FIG. 4 is a flow chart of a control system of a transport speed.
【図５】図５は１個のセンサを用いた実施例の図であ
る。FIG. 5 is a diagram of an embodiment using one sensor.
【図６】図６は図５の要部拡大図である。6 is an enlarged view of a main part of FIG.
【図７】図７は第２実施例の図である。FIG. 7 is a diagram of a second embodiment.
【図８】図８は図７の要部拡大図である。FIG. 8 is an enlarged view of a main part of FIG. 7.
【図９】図９は第２実施例の制御ブロック線図である。FIG. 9 is a control block diagram of the second embodiment.
【図１０】図１０は第３実施例の図である。FIG. 10 is a diagram of a third embodiment.
【図１１】図１１は第３実施例の制御ブロック線図であ
る。FIG. 11 is a control block diagram of the third embodiment.
【図１２】図１２は第４実施例の図である。FIG. 12 is a diagram of a fourth embodiment.
【図１３】図１３はブロック図である。FIG. 13 is a block diagram.
【図１４】図１４は従来の画像形成装置の内部構造の
例。FIG. 14 is an example of an internal structure of a conventional image forming apparatus.
１０３ 転写ユニット（転写手段） １０４ 定着ユニット（定着手段） １１１ 分離爪（分離手段） ２００，２１０，２２０ センサフラグ（ループ検出手
段） ２００ａ，２００ｂ，２１０ａ センサ ２２０ａ 変動量検出器 （ループ検出手段） ２３０ フラッパ （ループ検出手段） ２３０ｃ 角度検出器 （ループ検出手段） ３００，３３０ 用紙のループ量と定着器の回転速度の
伝達関数 ３０１，３３１ 制御器103 transfer unit (transfer means) 104 fixing unit (fixing means) 111 separating claw (separating means) 200, 210, 220 sensor flag (loop detecting means) 200a, 200b, 210a sensor 220a fluctuation amount detector (loop detecting means) 230 Flapper (loop detecting means) 230c Angle detector (loop detecting means) 300, 330 Transfer function of loop amount of paper and rotation speed of fixing device 301, 331 Controller
Claims (9)
た定着手段と転写手段を有する画像形成装置において、
分離手段により転写手段から分離された記録媒体を、そ
の分離部と定着手段の入口手前部の間でループを形成さ
せ、該記録媒体の形成するループ量を定着手段入口手前
部で検出するループ検出手段を有し、その検出ループ量
に基づいて定着手段の駆動手段の速度を制御することを
特徴とする画像形成装置。1. An image forming apparatus having a fixing unit and a transfer unit, each of which is provided with an independent driving unit,
Loop detection for forming a loop between the recording medium separated from the transfer means by the separating means and the entrance front part of the fixing means, and detecting the amount of loop formed by the recording medium at the entrance front part of the fixing means An image forming apparatus having means, and controlling the speed of the driving means of the fixing means based on the detected loop amount.
の形成するループ量の上限と下限を検知するセンサを有
し、前記ループ量の上限を検知したとき定着手段の駆動
手段の速度を速くし、また、前記ループ量の下限を検知
したとき定着手段の駆動手段の速度を遅くするように制
御を行って成ることを特徴とする請求項１に記載の画像
形成装置。2. The loop detecting means has a sensor for detecting an upper limit and a lower limit of a loop amount formed by a recording medium, and when the upper limit of the loop amount is detected, the speed of a fixing means driving means is increased. The image forming apparatus according to claim 1, further comprising: controlling so as to slow down the speed of the driving unit of the fixing unit when the lower limit of the loop amount is detected.
ンサを用いて記録媒体の形成するループ量の上限と下限
を検知することを特徴とする請求項１または２に記載の
画像形成装置。3. The image forming apparatus according to claim 1, wherein the loop detection unit detects the upper limit and the lower limit of the loop amount formed by the recording medium by using one sensor.
体分離検知手段として兼用することを特徴とする請求項
１，２または３に記載の画像形成装置。4. The image forming apparatus according to claim 1, wherein the loop detecting unit is also used as a recording medium separation detecting unit of the transfer unit.
に接し、該用紙のループ量に応じて変移する部材を有
し、該部材の変移量を検出し、該検出変移量を一定に保
つように定着手段の駆動手段の速度制御を行って成る請
求項１に記載の画像形成装置。5. The loop detection means has a member that is in contact with a recording medium and that changes in accordance with the loop amount of the sheet, detects the shift amount of the member, and keeps the detected shift amount constant. The image forming apparatus according to claim 1, wherein the speed of the driving unit of the fixing unit is controlled.
にループさせ、かつ、記録媒体のループ量に応じて、揺
動可能なレバー部材を有し、該レバー部材の変移角度を
検出し、該角度を一定に保つように定着手段の駆動手段
の速度制御を行って成ることを特徴とする請求項１に記
載の画像形成装置。6. A recording medium is looped upward in the vicinity of the separating portion of the transfer means, and a lever member is provided which can be swung according to the loop amount of the recording medium, and the displacement angle of the lever member is detected. 2. The image forming apparatus according to claim 1, wherein the speed of the driving unit of the fixing unit is controlled so as to keep the angle constant.
手段と定着手段の間の搬送経路直線上より自重方向にガ
イドするガイド手段を有し、転写手段と定着手段間での
記録媒体のループを下側に形成し、前記ガイド手段と記
録媒体間のギャップ量を検出する手段を有し、該検出ギ
ャップ量に基づいて定着手段の駆動手段の速度制御を行
って成ることを特徴とする画像形成装置。7. A loop of the recording medium between the transfer means and the fixing means, the guide means for guiding the recording medium separated from the transfer means in a self-weight direction from a straight line of a conveying path between the transfer means and the fixing means. And a means for detecting a gap amount between the guide means and the recording medium, and speed control of the driving means of the fixing means is performed based on the detected gap amount. Forming equipment.
着手段の直線上の記録媒体との角度を検出する手段を有
し、該角度を一定に保つように定着手段の駆動手段の速
度制御を行って成ることを特徴とする請求項７に記載の
画像形成装置。8. A means for detecting the angle between the transfer means and the recording medium on the straight line of the fixing means near the separation portion of the transfer means, and speed control of the driving means of the fixing means so as to keep the angle constant. The image forming apparatus according to claim 7, wherein the image forming apparatus comprises:
速度制御を行って成ることを特徴とする請求項１，２，
３，４，５，６，７または８に記載の画像形成装置。9. The method according to claim 1, wherein speed control is performed not for the fixing means but for the driving means of the transfer means.
The image forming apparatus described in 3, 4, 5, 6, 7 or 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6049873A JPH07234604A (en) | 1994-02-23 | 1994-02-23 | Image forming device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6049873A JPH07234604A (en) | 1994-02-23 | 1994-02-23 | Image forming device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07234604A true JPH07234604A (en) | 1995-09-05 |
Family
ID=12843175
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6049873A Pending JPH07234604A (en) | 1994-02-23 | 1994-02-23 | Image forming device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07234604A (en) |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1353243A2 (en) * | 2002-04-09 | 2003-10-15 | Xerox Corporation | Xerographic fusing apparatus |
| US6783026B2 (en) * | 2003-01-15 | 2004-08-31 | Xerox Corporation | Systems and methods providing bi-directional passage of an object via an articulated member |
| JP2006010722A (en) * | 2004-06-22 | 2006-01-12 | Konica Minolta Business Technologies Inc | Image forming apparatus |
| JP2006030268A (en) * | 2004-07-12 | 2006-02-02 | Konica Minolta Business Technologies Inc | Image forming apparatus |
| JP2006182465A (en) * | 2004-12-27 | 2006-07-13 | Canon Inc | Sheet detection device and image forming device |
| US7251426B2 (en) | 2004-09-06 | 2007-07-31 | Canon Kabushiki Kaisha | Image forming apparatus with loop detection and conveying speed control based thereon |
| US7409172B2 (en) | 2005-03-29 | 2008-08-05 | Canon Kabushiki Kaisha | Image forming apparatus |
| JP2009053612A (en) * | 2007-08-29 | 2009-03-12 | Canon Inc | Image forming apparatus |
| JP2009155007A (en) * | 2007-12-25 | 2009-07-16 | Canon Inc | Image forming apparatus |
| US8121507B2 (en) | 2007-07-31 | 2012-02-21 | Kyocera Mita Corporation | Image forming apparatus preventing sheet transfer deviation or slippage through fine detection of loop amount |
| US8626051B2 (en) | 2009-12-22 | 2014-01-07 | Canon Kabushiki Kaisha | Image forming apparatus with conveying portions having a loop detector with contact portion for contacting the sheet |
| JP2014102303A (en) * | 2012-11-19 | 2014-06-05 | Kyocera Document Solutions Inc | Image forming apparatus |
| US8774664B2 (en) | 2006-05-15 | 2014-07-08 | Canon Kabushiki Kaisha | Image forming apparatus with loop detection and conveyance speed control |
| US9244395B2 (en) | 2013-04-25 | 2016-01-26 | Canon Kabushiki Kaisha | Image forming apparatus to control sheet conveyance speed |
| US9869953B2 (en) | 2016-02-05 | 2018-01-16 | Canon Kabushiki Kaisha | Image forming apparatus |
| JP2018072769A (en) * | 2016-11-04 | 2018-05-10 | シャープ株式会社 | Image forming apparatus |
-
1994
- 1994-02-23 JP JP6049873A patent/JPH07234604A/en active Pending
Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1353243A2 (en) * | 2002-04-09 | 2003-10-15 | Xerox Corporation | Xerographic fusing apparatus |
| US6783026B2 (en) * | 2003-01-15 | 2004-08-31 | Xerox Corporation | Systems and methods providing bi-directional passage of an object via an articulated member |
| JP4539188B2 (en) * | 2004-06-22 | 2010-09-08 | コニカミノルタビジネステクノロジーズ株式会社 | Image forming apparatus |
| JP2006010722A (en) * | 2004-06-22 | 2006-01-12 | Konica Minolta Business Technologies Inc | Image forming apparatus |
| JP2006030268A (en) * | 2004-07-12 | 2006-02-02 | Konica Minolta Business Technologies Inc | Image forming apparatus |
| JP4649898B2 (en) * | 2004-07-12 | 2011-03-16 | コニカミノルタビジネステクノロジーズ株式会社 | Image forming apparatus |
| US7251426B2 (en) | 2004-09-06 | 2007-07-31 | Canon Kabushiki Kaisha | Image forming apparatus with loop detection and conveying speed control based thereon |
| US7509066B2 (en) | 2004-09-06 | 2009-03-24 | Canon Kabushiki Kaisha | Image forming apparatus with loop detection and conveying speed control based thereon |
| JP4612836B2 (en) * | 2004-12-27 | 2011-01-12 | キヤノン株式会社 | Sheet detecting apparatus and image forming apparatus |
| JP2006182465A (en) * | 2004-12-27 | 2006-07-13 | Canon Inc | Sheet detection device and image forming device |
| US7409172B2 (en) | 2005-03-29 | 2008-08-05 | Canon Kabushiki Kaisha | Image forming apparatus |
| US8774664B2 (en) | 2006-05-15 | 2014-07-08 | Canon Kabushiki Kaisha | Image forming apparatus with loop detection and conveyance speed control |
| US8121507B2 (en) | 2007-07-31 | 2012-02-21 | Kyocera Mita Corporation | Image forming apparatus preventing sheet transfer deviation or slippage through fine detection of loop amount |
| JP4579953B2 (en) * | 2007-08-29 | 2010-11-10 | キヤノン株式会社 | Image forming apparatus |
| US7941063B2 (en) | 2007-08-29 | 2011-05-10 | Canon Kabushiki Kaisha | Image forming apparatus with loop control |
| JP2009053612A (en) * | 2007-08-29 | 2009-03-12 | Canon Inc | Image forming apparatus |
| US8131203B2 (en) | 2007-12-25 | 2012-03-06 | Canon Kabushiki Kaisha | Image forming apparatus having retractable sheet loop detecting unit |
| JP2009155007A (en) * | 2007-12-25 | 2009-07-16 | Canon Inc | Image forming apparatus |
| US8626051B2 (en) | 2009-12-22 | 2014-01-07 | Canon Kabushiki Kaisha | Image forming apparatus with conveying portions having a loop detector with contact portion for contacting the sheet |
| JP2014102303A (en) * | 2012-11-19 | 2014-06-05 | Kyocera Document Solutions Inc | Image forming apparatus |
| US9244395B2 (en) | 2013-04-25 | 2016-01-26 | Canon Kabushiki Kaisha | Image forming apparatus to control sheet conveyance speed |
| US9869953B2 (en) | 2016-02-05 | 2018-01-16 | Canon Kabushiki Kaisha | Image forming apparatus |
| JP2018072769A (en) * | 2016-11-04 | 2018-05-10 | シャープ株式会社 | Image forming apparatus |
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