JP2017003957A - Developing device, process cartridge, and image forming apparatus - Google Patents

Developing device, process cartridge, and image forming apparatus Download PDF

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JP2017003957A
JP2017003957A JP2015172004A JP2015172004A JP2017003957A JP 2017003957 A JP2017003957 A JP 2017003957A JP 2015172004 A JP2015172004 A JP 2015172004A JP 2015172004 A JP2015172004 A JP 2015172004A JP 2017003957 A JP2017003957 A JP 2017003957A
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developer
developing
magnetic
carrier
developing device
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嘉子 小川
Yoshiko Ogawa
嘉子 小川
浅見 彰
Akira Asami
彰 浅見
保伸 清水
Yasunobu Shimizu
保伸 清水
嘉治 岸
Yoshiharu Kishi
嘉治 岸
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Ricoh Co Ltd
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Ricoh Co Ltd
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Abstract

PROBLEM TO BE SOLVED: To make it possible to suppress a reduction over time in the amount of a developer conveyed to a development area.SOLUTION: There is provided a developing device comprising: a developer carrier that has magnetic field generation means arranged inside a hollow body, and rotates by itself while carrying a two-component developer consisting of a magnetic carrier and toner on an outer surface of the hollow body to convey the developer; and a developer regulation member that consists of a non-magnetic member and magnetic member and regulates the amount of the developer on the developer carrier, where the magnetic member is installed on the upstream side with respect to the non-magnetic member in a direction where the developer is conveyed by the developer carrier, wherein a portion of the non-magnetic member closest to the outer surface of the developer carrier is arranged opposite to a portion of the outer surface of the developer carrier at which a direction of a magnetic force of a tangential direction component acting on the developer on the developing sleeve because of the presence of a magnetic field generated by the magnetic field generation means on the outer surface of the developer carrier, is directed to the downstream side in the direction where the developer is conveyed by the developer carrier.SELECTED DRAWING: Figure 8

Description

本発明は、現像装置、プロセスカートリッジ及び画像形成装置に関するものである。   The present invention relates to a developing device, a process cartridge, and an image forming apparatus.

従来、現像剤担持体としての現像スリーブに担持したトナーと磁性キャリアとからなる二成分の現像剤を現像スリーブの表面移動により現像剤規制部材の先端部と現像スリーブの外表面との間の隙間(規制ギャップ)を通過させて所定の量に規制された現像剤を感光体と対向する現像領域へ搬送する現像装置が知られている。   Conventionally, a gap between the tip of the developer regulating member and the outer surface of the developing sleeve is obtained by moving the two-component developer composed of toner and magnetic carrier carried on the developing sleeve as a developer carrying member by moving the surface of the developing sleeve. 2. Description of the Related Art There is known a developing device that passes a (regulating gap) and transports a developer that is regulated to a predetermined amount to a developing area that faces a photoreceptor.

例えば、特許文献1には、磁性部材としての磁性板が非磁性部材としての非磁性板の現像スリーブによる現像剤搬送方向上流側の側面に固定され、非磁性板によって現像スリーブ上の現像剤の量を規制している現像装置が開示されている。
この現像装置では、中空体の現像スリーブに内蔵されている磁界発生手段としてのマグネットローラの汲み上げ磁極の磁力によって現像スリーブ上に汲み上げられる。その汲み上げられた現像剤は、搬送磁極と、これよりも現像スリーブによる現像剤搬送方向下流側(以下、下流側という。)にあって搬送磁極とは逆の極性の規制磁極との間の磁界の作用で現像スリーブ上に拘束される。そして、現像スリーブの回転に伴って現像剤規制部材の非磁性板と現像スリーブとの隙間(規制ギャップ)に搬送される。その規制ギャップに搬送される現像剤は、非磁性板のみの現像剤規制部材に比べて、磁性板と規制磁極との間の強い磁界によってより略直線状に穂立ちし、現像スリーブの回転により当該規制ギャップを通過することで狙いの量に規制できるとされている。
For example, in Patent Document 1, a magnetic plate as a magnetic member is fixed to a side surface on the upstream side of a developer conveying direction by a developing sleeve of a nonmagnetic plate as a nonmagnetic member, and the developer on the developing sleeve is fixed by the nonmagnetic plate. A developing device that regulates the amount is disclosed.
In this developing device, the toner is pumped onto the developing sleeve by the magnetic force of the magnetic pole pumped up by a magnet roller as a magnetic field generating means built in the hollow developing sleeve. The developer drawn up is a magnetic field between the transport magnetic pole and a regulating magnetic pole on the downstream side in the developer transport direction by the developing sleeve (hereinafter referred to as the downstream side) and having a polarity opposite to the transport magnetic pole. It is restrained on the developing sleeve by the action of. Then, with the rotation of the developing sleeve, it is conveyed to a gap (regulating gap) between the nonmagnetic plate of the developer regulating member and the developing sleeve. The developer transported to the regulation gap rises more substantially in a straight line due to the strong magnetic field between the magnetic plate and the regulation magnetic pole than the developer regulation member having only the non-magnetic plate, and the developer sleeve rotates. It is said that the target amount can be regulated by passing through the regulation gap.

一般に、現像装置では、現像スリーブ内部のマグネットローラにおける磁極による磁界の作用によって、現像スリーブ上の現像剤に対して働く現像スリーブ表面での接線方向成分をもつ磁気力(以下、接線方向磁気力という。)が生じる。その接線方向磁気力の現像スリーブ上の現像剤に作用する向きが下流側へ向いていると、その作用の向きは現像スリーブの回転による現像剤搬送方向と同じであるので、現像剤の搬送は促進される。逆に、接線方向磁気力の作用の向きが現像スリーブによる現像剤搬送方向上流側(以下、上流側という。)へ向いていると、その作用の向きは現像スリーブの回転による現像剤搬送方向と逆の向きであるので、現像剤の搬送を阻害してしまう。   In general, in a developing device, a magnetic force having a tangential component on the surface of the developing sleeve acting on the developer on the developing sleeve (hereinafter referred to as a tangential magnetic force) due to the action of a magnetic field by a magnetic pole in a magnet roller inside the developing sleeve. .) Occurs. When the direction of the tangential magnetic force acting on the developer on the developing sleeve is directed to the downstream side, the direction of the action is the same as the developer conveying direction by the rotation of the developing sleeve. Promoted. Conversely, when the direction of the action of the tangential magnetic force is directed to the upstream side of the developer conveying direction by the developing sleeve (hereinafter referred to as the upstream side), the direction of the action is the developer conveying direction by the rotation of the developing sleeve. Since it is the reverse direction, the conveyance of the developer is hindered.

通常、例えば経時により現像剤の劣化が進むと、現像剤に含まれる添加剤が磁性キャリアに付着して現像剤の流動性が落ちて搬送抵抗が高まる。規制ギャップの通過にあたって、その現像剤の一部が現像スリーブの回転に追従し難くなり、現像剤の通過量が減少する。上記特許文献1に開示の現像装置では、非磁性板の先端部に対向する現像スリーブ表面上の位置(以下、規制位置という。)において、接線方向磁気力の向きは、上流側へ向いている。その規制位置では、現像剤の搬送が阻害される。上記特許文献1に開示の現像装置では、現像剤の劣化が進むと、その規制位置での規制ギャップにおける現像剤の通過量は、さらに減少する。よって、現像領域への現像剤搬送量が経時により低下してしまう。   In general, for example, when the developer deteriorates with time, the additive contained in the developer adheres to the magnetic carrier, and the fluidity of the developer is lowered to increase the transport resistance. When passing through the regulation gap, a part of the developer becomes difficult to follow the rotation of the developing sleeve, and the amount of developer passing is reduced. In the developing device disclosed in Patent Document 1, the direction of the tangential magnetic force is directed upstream at a position on the surface of the developing sleeve (hereinafter referred to as a regulation position) that faces the tip of the nonmagnetic plate. . At the restricted position, the developer conveyance is hindered. In the developing device disclosed in Patent Document 1, as the developer progresses, the amount of developer passing through the restriction gap at the restriction position further decreases. Therefore, the amount of developer transported to the development area decreases with time.

上述した課題を解決するために、請求項1の発明は、磁界発生手段を中空体内に配置し、該磁界発生手段の磁力により該中空体の外表面上に磁性キャリアとトナーとからなる二成分の現像剤を担持して自身が回転することでその現像剤を搬送する現像剤担持体と、非磁性部材と磁性部材とからなり、かつ、該現像剤担持体上の現像剤の量を規制する現像剤規制部材とを備え、前記磁性部材は前記非磁性部材に対し前記現像剤担持体による現像剤搬送方向上流側に設置させている現像装置において、前記現像剤担持体の外表面での前記磁界発生手段による磁界によって現像剤担持体上の現像剤に対して働く接線方向成分の磁気力の前記現像剤担持体上の前記現像剤に対し作用する向きが前記現像剤担持体による現像剤搬送方向下流側に向いている前記現像剤担持体の外表面の部分に、前記現像剤担持体の外表面に最も近い前記非磁性部材の部分が対向していることを特徴とするものである。   In order to solve the above-mentioned problems, the invention of claim 1 is a two-component system comprising a magnetic field generating means arranged in a hollow body, and a magnetic carrier and toner on the outer surface of the hollow body by the magnetic force of the magnetic field generating means. A developer carrying body that carries the developer and conveys the developer by rotating itself, a non-magnetic member and a magnetic member, and regulates the amount of developer on the developer carrying body A developer regulating member that is disposed on the upstream side in the developer conveying direction of the developer carrier with respect to the non-magnetic member. The direction of the magnetic force of the tangential direction component acting on the developer on the developer carrier by the magnetic field generated by the magnetic field generating means acts on the developer on the developer carrier. Facing downstream in the transport direction Wherein the portion of the outer surface of the developer carrying member, the nearest part of the non-magnetic member on an outer surface of said developer carrying member is characterized in that it is opposed.

本発明によれば、現像領域への現像剤搬送量の経時による低下を抑制することができるという特有の効果が得られる。   According to the present invention, it is possible to obtain a specific effect that it is possible to suppress a decrease in the amount of developer transported to the development area over time.

実施形態に係る複写機の概略構成図。1 is a schematic configuration diagram of a copier according to an embodiment. プロセスカートリッジの奥側の斜視図。The perspective view of the back side of a process cartridge. 同プロセスカートリッジの手前側斜視図。FIG. 3 is a front perspective view of the process cartridge. 同プロセスカートリッジの概略構成図。FIG. 2 is a schematic configuration diagram of the process cartridge. 実施形態の現像装置の概略構成図。1 is a schematic configuration diagram of a developing device according to an embodiment. 従来の現像装置における現像剤規制部材と現像ローラとを現像ローラの軸方向から見たときの説明図。Explanatory drawing when the developer control member and developing roller in the conventional developing device are seen from the axial direction of the developing roller. 本実施形態の現像装置における現像剤規制部材と現像ローラとを現像ローラの軸方向から見たときの説明図。FIG. 3 is an explanatory diagram when a developer regulating member and a developing roller in the developing device of the present embodiment are viewed from the axial direction of the developing roller. (a)は、図6の従来の現像剤規制部材を所定の位置に配置したときの現像スリーブ表面での接線方向磁気力変化を示すグラフ、(b)は、図7の本実施形態の現像装置における現像剤規制部材を所定の位置に配置したときの現像スリーブ表面での接線方向磁気力変化を示すグラフ。(A) is a graph showing a change in tangential magnetic force on the surface of the developing sleeve when the conventional developer regulating member of FIG. 6 is arranged at a predetermined position, and (b) is a development of the present embodiment of FIG. The graph which shows the tangential magnetic force change in the surface of a developing sleeve when the developer control member in an apparatus is arrange | positioned in a predetermined position. 現像スリーブ表面での接線方向磁気力と現像剤搬送量低下率との関係を示すグラフ。The graph which shows the relationship between the tangential direction magnetic force in the image development sleeve surface, and a developer conveyance amount fall rate. (a)は、図7の現像剤規制部材が撓んでいないとき上方から見た説明図、(b)は、図7の現像剤規制部材が撓んだとき上方から見た説明図。7A is an explanatory view seen from above when the developer regulating member of FIG. 7 is not bent, and FIG. 8B is an explanatory view seen from above when the developer regulating member of FIG. 7 is bent. (a)は、別の構成例の現像剤規制部材が撓んでいないとき上方から見た説明図、(b)は、別の構成例の現像剤規制部材が撓んだとき上方から見た説明図。(A) is an explanatory view seen from above when the developer regulating member of another configuration example is not bent, and (b) is an explanation seen from above when the developer regulating member of another configuration example is bent. Figure. 別の構成例の現像剤規制部材の幅方向における中央部が撓む前の中央部及び両端部の現像スリーブ表面での接線方向磁気力変化を示すグラフ。The graph which shows the tangential magnetic force change in the developing sleeve surface of the center part and both ends before the center part in the width direction of the developer control member of another structural example bends. 別の構成例の現像剤規制部材の幅方向における中央部が撓んだ後の中央部及び両端部の現像スリーブ表面での接線方向磁気力変化を示すグラフ。The graph which shows the tangential magnetic force change in the developing sleeve surface of the center part and both ends after the center part in the width direction of the developer control member of another structural example bends.

以下、本発明を適用した画像形成装置として、複数の感光体が並行配設されたタンデム型のカラーレーザー複写機(以下、単に「複写機」という)500の一実施形態(以下、単に「実施形態」という)について説明する。   Hereinafter, as an image forming apparatus to which the present invention is applied, an embodiment (hereinafter simply referred to as “implementation”) of a tandem type color laser copying machine (hereinafter simply referred to as “copying machine”) 500 in which a plurality of photoconductors are arranged in parallel. Form)).

図1は、実施形態に係る複写機の概略構成図である。
この複写機はプリンタ部100、これを載せる給紙装置200、プリンタ部100の上に固定されたスキャナ300などを備えている。また、このスキャナ300の上に固定された原稿自動搬送装置400なども備えている。
FIG. 1 is a schematic configuration diagram of a copying machine according to an embodiment.
The copier includes a printer unit 100, a paper feeding device 200 on which the printer unit 100 is placed, a scanner 300 fixed on the printer unit 100, and the like. An automatic document feeder 400 fixed on the scanner 300 is also provided.

プリンタ部100は、イエロー(Y)、マゼンタ(M)、シアン(C)、黒(K)の各色の画像を形成するための4組のプロセスカートリッジ18Y,M,C,Kからなる画像形成ユニット20を備えている。各符号の数字の後に付されたY,M,C,Kは、イエロー、シアン、マゼンタ、ブラック用の部材であることを示している(以下同様)。   The printer unit 100 includes an image forming unit including four sets of process cartridges 18Y, 18M, 18C, and 18K for forming images of each color of yellow (Y), magenta (M), cyan (C), and black (K). 20 is provided. Y, M, C, and K added after the numbers of the respective symbols indicate members for yellow, cyan, magenta, and black (the same applies hereinafter).

プロセスカートリッジ18Y,M,C,Kの他には、光書込ユニット21、中間転写ユニット17、二次転写装置22、レジストローラ対49、ベルト定着方式の定着装置25などが配設されている。   In addition to the process cartridges 18Y, 18M, 18C, and 18K, an optical writing unit 21, an intermediate transfer unit 17, a secondary transfer device 22, a resist roller pair 49, a belt fixing type fixing device 25, and the like are disposed. .

光書込ユニット21は、光源、ポリゴンミラー、f−θレンズ、反射ミラーなどを有し、画像データに基づいて後述の感光体の表面にレーザ光を照射する。   The optical writing unit 21 includes a light source, a polygon mirror, an f-θ lens, a reflection mirror, and the like, and irradiates the surface of a photoconductor described later with laser light based on image data.

図2は、プロセスカートリッジ18の奥側の斜視図であり、図3は、プロセスカートリッジ18の手前側斜視図である。図4は、プロセスカートリッジ18の概略構成図である。
ここで、各プロセスカートリッジ18の構成はほぼ同様であるので、以下の説明では色分け用の添え字(Y,C,M,K)を省略して、プロセスカートリッジ18の構成及び動作について説明する。
プロセスカートリッジ18は、図2中の矢印Aで示す方向に向けて装置手前側から奥側へ複写機本体内の装着空間へ挿入されることで、複写機本体に装着される。プロセスカートリッジ18は、ドラム状の感光体1と、感光体1の周りに配置されたドラムクリーニングユニット72、帯電ユニット71及び現像装置4を備えている。現像装置4において、現像ケーシング4aの側面には放熱部120が形成されている。
FIG. 2 is a perspective view of the back side of the process cartridge 18, and FIG. 3 is a front perspective view of the process cartridge 18. FIG. 4 is a schematic configuration diagram of the process cartridge 18.
Here, since the configuration of each process cartridge 18 is almost the same, in the following description, the configuration and operation of the process cartridge 18 will be described with the subscripts (Y, C, M, K) for color coding omitted.
The process cartridge 18 is mounted in the copying machine main body by being inserted into the mounting space in the copying machine main body from the front side of the apparatus toward the back side in the direction indicated by the arrow A in FIG. The process cartridge 18 includes a drum-shaped photoconductor 1, a drum cleaning unit 72 disposed around the photoconductor 1, a charging unit 71, and a developing device 4. In the developing device 4, a heat radiating portion 120 is formed on the side surface of the developing casing 4a.

ドラムクリーニングユニット72は、感光体1の回転軸方向に長尺な弾性部材であるクリーニングブレード72aと、排出スクリュ72bとから主に構成されている。   The drum cleaning unit 72 mainly includes a cleaning blade 72a that is an elastic member that is long in the direction of the rotation axis of the photoreceptor 1, and a discharge screw 72b.

クリーニングブレード72aにおけるその長尺方向に延びる一辺(当接辺)をエッジ部として感光体1の表面に押しつけて、感光体1表面上の転写残トナー等の不要な付着物を引き離し除去する。   One side (contact side) extending in the longitudinal direction of the cleaning blade 72a is pressed against the surface of the photoreceptor 1 as an edge portion, and unnecessary deposits such as transfer residual toner on the surface of the photoreceptor 1 are separated and removed.

除去されたトナーは、排出スクリュ72bによってドラムクリーニングユニット72の外に排出される。また、ドラムクリーニングユニット72には、直流電圧を印加された除電部材72cが配置されている。   The removed toner is discharged out of the drum cleaning unit 72 by the discharge screw 72b. The drum cleaning unit 72 is provided with a charge removal member 72c to which a DC voltage is applied.

帯電ユニット71は、感光体1に当接するように配置された帯電ローラ71aと、この帯電ローラ71aに当接して回転する帯電ローラクリーナ71bとから主として構成されている。   The charging unit 71 is mainly composed of a charging roller 71a disposed so as to contact the photoreceptor 1, and a charging roller cleaner 71b rotating in contact with the charging roller 71a.

現像装置4は、図4中の矢印I方向に表面移動しながら感光体1の表面の潜像にトナーを供給し、現像する現像剤担持体としての現像ローラ5と、トナーとキャリアとからなる二成分現像剤現像剤を貯留する現像剤貯留部3を形成する現像ケーシング4aとを備えている。   The developing device 4 includes a developing roller 5 as a developer carrying member for supplying and developing toner to the latent image on the surface of the photoreceptor 1 while moving in the direction of arrow I in FIG. 4, and toner and a carrier. And a developing casing 4a that forms a developer reservoir 3 for storing a two-component developer.

現像ローラ5は、内部に固設された複数の磁石からなるマグネットローラ5bと、マグネットローラ5bを内包しマグネットローラ5bの周囲を回転する非磁性材料からなる円筒形状の現像スリーブ5aとから構成される。複数の磁極を形成するマグネットローラ5bの周囲を現像スリーブ5aが回転することで、その回転にともない現像剤が現像ローラ5上を移動する。   The developing roller 5 includes a magnet roller 5b made of a plurality of magnets fixed inside, and a cylindrical developing sleeve 5a made of a nonmagnetic material that includes the magnet roller 5b and rotates around the magnet roller 5b. The As the developing sleeve 5a rotates around the magnet roller 5b forming a plurality of magnetic poles, the developer moves on the developing roller 5 with the rotation.

現像ローラ5の現像スリーブ5aに現像バイアス印加手段たる現像電源150から現像バイアスが印加されることにより、現像領域では現像スリーブ5aと感光体1との間に現像電界が形成される。この現像電界により、現像領域では現像スリーブ5aの表面上の現像剤中のトナーが感光体1の表面上の潜像に供給され、感光体1上の潜像が現像される。本実施形態では、現像バイアスとして、ピーク電圧が1[kV]以上ACバイアスを現像スリーブ5aに印加している。現像バイアスを、ACバイアスとすることで、DCバイアスに比べてキャリアから離れるトナーを増加させ、現像能力を向上させることができ、鮮鋭性の高いシャープな画像を得ることができる。   A developing bias is applied to the developing sleeve 5a of the developing roller 5 from a developing power supply 150 serving as a developing bias applying means, whereby a developing electric field is formed between the developing sleeve 5a and the photoreceptor 1 in the developing region. By this developing electric field, in the developing area, toner in the developer on the surface of the developing sleeve 5a is supplied to the latent image on the surface of the photoreceptor 1, and the latent image on the photoreceptor 1 is developed. In this embodiment, an AC bias having a peak voltage of 1 [kV] or more is applied to the developing sleeve 5a as the developing bias. By setting the developing bias to an AC bias, it is possible to increase the amount of toner that is away from the carrier as compared with the DC bias, improve the developing ability, and obtain a sharp image with high sharpness.

また、現像ローラ5の供給スクリュ8との対向部よりも現像スリーブによる現像剤搬送方向下流側には、現像ローラ5に供給された現像剤を現像に適した厚さに規制する現像剤規制部材としてのドクタブレード12を備えている。   Further, a developer regulating member that regulates the developer supplied to the developing roller 5 to a thickness suitable for development, on the downstream side in the developer conveying direction by the developing sleeve from the portion facing the supply screw 8 of the developing roller 5. The doctor blade 12 is provided.

現像ケーシング4aは第一仕切り壁133と第二仕切り壁134とを有しており、現像剤貯留部3は、第一仕切り壁133と第二仕切り壁134とにより、供給搬送路9と回収搬送路7と攪拌搬送路10とに仕切られている。   The developing casing 4 a has a first partition wall 133 and a second partition wall 134, and the developer storage unit 3 includes a supply transport path 9 and a recovery transport by the first partition wall 133 and the second partition wall 134. It is partitioned into a path 7 and an agitation transport path 10.

現像剤供給部たる供給搬送路9には、現像ローラ5に現像剤を供給しながら図4中の奥方向に現像剤を搬送する供給搬送部材としての供給スクリュ8が配置されている。供給スクリュ8は、回転軸とこの回転軸に設けられた羽部とを備え、図4中の矢印M方向に回転することにより軸方向に現像剤を搬送する現像剤搬送スクリュである。   A supply screw 8 as a supply conveyance member that conveys the developer in the depth direction in FIG. 4 while supplying the developer to the developing roller 5 is disposed in the supply conveyance path 9 that is a developer supply unit. The supply screw 8 is a developer conveying screw that includes a rotating shaft and a blade portion provided on the rotating shaft and conveys the developer in the axial direction by rotating in the direction of arrow M in FIG.

現像ローラ5の感光体1との対向部である現像部よりも現像スリーブによる現像剤搬送方向下流側に配置され、現像部を通過した現像済みの現像剤は、現像剤回収部たる回収搬送路7に落下し回収される。   The developer that has been developed and has passed through the developing unit is disposed downstream of the developing unit, which is the portion of the developing roller 5 facing the photoreceptor 1, with respect to the developer conveying direction by the developing sleeve. It falls to 7 and is collected.

現像剤回収部たる回収搬送路7には、回収した回収現像剤を供給スクリュ8と同方向に搬送する回収搬送部材としての回収スクリュ6を備えている。供給スクリュ8を備えた供給搬送路9は現像ローラ5の横方向に、回収スクリュ6を備えた回収搬送路7は現像ローラ5の下方に並設されている。   The collection conveyance path 7 as a developer collection unit includes a collection screw 6 as a collection conveyance member that conveys the collected collection developer in the same direction as the supply screw 8. A supply conveyance path 9 provided with the supply screw 8 is arranged in the lateral direction of the developing roller 5, and a collection conveyance path 7 provided with the collection screw 6 is arranged in parallel below the development roller 5.

攪拌搬送部たる攪拌搬送路10は、供給搬送路9の下方で回収搬送路7に並列して設けている。攪拌搬送路10は、現像剤を攪拌しながら供給スクリュ8とは逆方向である図4中の手前側に搬送するために、図4中の矢印C方向に回転する攪拌搬送部材としての攪拌スクリュ11を備えている。   The agitation conveyance path 10 serving as the agitation conveyance unit is provided in parallel with the collection conveyance path 7 below the supply conveyance path 9. The agitating and conveying path 10 is an agitating screw serving as an agitating and conveying member that rotates in the direction of arrow C in FIG. 4 in order to convey the developer to the near side in FIG. 11 is provided.

供給搬送路9と攪拌搬送路10とは第一仕切り壁133によって仕切られている。第一仕切り壁133の供給搬送路9と攪拌搬送路10とを仕切る箇所は図4中の手前側と奥側との両端は開口部となっており、供給搬送路9と攪拌搬送路10とが連通している。   The supply conveyance path 9 and the agitation conveyance path 10 are partitioned by a first partition wall 133. The part which partitions the supply conveyance path 9 and the stirring conveyance path 10 of the 1st partition wall 133 into the both ends of the near side and the back side in FIG. 4 is an opening, and the supply conveyance path 9 and the stirring conveyance path 10 Are communicating.

なお、供給搬送路9と回収搬送路7も第一仕切り壁133によって仕切られているが、第一仕切り壁133の供給搬送路9と回収搬送路7とを仕切る箇所には開口部を設けていない。   Note that the supply conveyance path 9 and the recovery conveyance path 7 are also partitioned by the first partition wall 133, but an opening is provided in the first partition wall 133 where the supply conveyance path 9 and the recovery conveyance path 7 are partitioned. Absent.

また、攪拌搬送路10と回収搬送路7との2つの搬送路は第二仕切り壁134によって仕切られている。第二仕切り壁134は、回収スクリュ6による搬送方向下流側が開口部となっており、攪拌搬送路10と回収搬送路7とが連通している。   Further, the two conveyance paths of the agitation conveyance path 10 and the collection conveyance path 7 are partitioned by a second partition wall 134. The second partition wall 134 has an opening on the downstream side in the conveyance direction by the collection screw 6, and the stirring conveyance path 10 and the collection conveyance path 7 communicate with each other.

また、供給搬送路9には、供給搬送路9内の現像剤が所定の嵩を越えた場合にその一部を現像装置4の外部に排出する現像剤排出口94を有している。さらに、現像剤排出口94から排出された現像剤を現像装置4の外部に搬送する排出搬送スクリュ2aを備えた排出搬送路2も有している。   Further, the supply conveyance path 9 has a developer discharge port 94 for discharging a part of the developer in the supply conveyance path 9 to the outside of the developing device 4 when the developer exceeds a predetermined volume. Further, it also has a discharge conveyance path 2 including a discharge conveyance screw 2 a for conveying the developer discharged from the developer discharge port 94 to the outside of the developing device 4.

排出搬送路2は、供給搬送路9の搬送方向下流側で仕切り壁135を挟んで供給搬送路9と隣り合うように配置され、現像剤排出口94は供給搬送路9と排出搬送路2とを連通するように仕切り壁135に設けられた開口である。   The discharge conveyance path 2 is disposed on the downstream side in the conveyance direction of the supply conveyance path 9 so as to be adjacent to the supply conveyance path 9 with the partition wall 135 interposed therebetween, and the developer discharge port 94 is connected to the supply conveyance path 9 and the discharge conveyance path 2. Is an opening provided in the partition wall 135 so as to communicate with each other.

帯電手段たる帯電ユニット71によって、感光体1の表面は一様帯電される。帯電処理が施された感光体1の表面には、光書込ユニット21によって変調及び偏向されたレーザ光が照射される。すると、照射部(露光部)の電位が減衰する。この減衰により、感光体1表面に静電潜像が形成される。形成された静電潜像は現像手段たる現像装置4によって現像されてトナー像となる。   The surface of the photoreceptor 1 is uniformly charged by the charging unit 71 serving as charging means. The surface of the photoreceptor 1 subjected to the charging process is irradiated with laser light modulated and deflected by the optical writing unit 21. Then, the potential of the irradiation part (exposure part) is attenuated. By this attenuation, an electrostatic latent image is formed on the surface of the photoreceptor 1. The formed electrostatic latent image is developed by the developing device 4 as developing means to become a toner image.

感光体1上に形成されたトナー像は、後述の中間転写ベルト110に一次転写される。一次転写後の感光体1の表面は、ドラムクリーニングユニット72のクリーニングブレード72aによって転写残トナーがクリーニングされる。クリーニングされた感光体1は、除電部材72cによって除電される。そして、帯電ユニット71によって一様帯電せしめられて、初期状態に戻る。   The toner image formed on the photoreceptor 1 is primarily transferred to an intermediate transfer belt 110 described later. The surface of the photoreceptor 1 after the primary transfer is cleaned of the transfer residual toner by the cleaning blade 72a of the drum cleaning unit 72. The cleaned photoreceptor 1 is neutralized by the neutralizing member 72c. Then, it is uniformly charged by the charging unit 71 and returns to the initial state.

以上のような一連のプロセスは、プロセスカートリッジ18Y,M,C,Kについて同様である。   The series of processes as described above are the same for the process cartridges 18Y, 18M, 18C, and 18K.

次に、図1を用いて、中間転写ユニットについて説明する。
中間転写ユニット17は、中間転写ベルト110やベルトクリーニング装置90などを有している。また、張架ローラ14、駆動ローラ15、二次転写バックアップローラ16、4つの一次転写バイアスローラ62Y,M,C,Kなども有している。
Next, the intermediate transfer unit will be described with reference to FIG.
The intermediate transfer unit 17 includes an intermediate transfer belt 110, a belt cleaning device 90, and the like. Further, it also includes a tension roller 14, a driving roller 15, a secondary transfer backup roller 16, four primary transfer bias rollers 62Y, M, C, and K.

中間転写ベルト110は、張架ローラ14を含む複数のローラによってテンション張架されている。そして、ベルト駆動モータによって駆動される駆動ローラ15の回転によって図中時計回りに無端移動せしめられる。   The intermediate transfer belt 110 is tensioned by a plurality of rollers including the tension roller 14. Then, it is endlessly moved clockwise in the figure by the rotation of the driving roller 15 driven by the belt driving motor.

4つの一次転写バイアスローラ62Y,M,C,Kは、それぞれ中間転写ベルト110の内周面側に接触するように配設され、電源から一次転写バイアスの印加を受ける。また、中間転写ベルト110をその内周面側から感光体1Y,M,C,Kに向けて押圧してそれぞれ一次転写ニップを形成する。各一次転写ニップには、一次転写バイアスの影響により、感光体と一次転写バイアスローラとの間に一次転写電界が形成される。   The four primary transfer bias rollers 62Y, 62M, 62C, and 62K are disposed so as to be in contact with the inner peripheral surface side of the intermediate transfer belt 110, respectively, and receive a primary transfer bias from a power source. Further, the intermediate transfer belt 110 is pressed toward the photoreceptors 1Y, 1M, 1C, and 1K from the inner peripheral surface side to form primary transfer nips. In each primary transfer nip, a primary transfer electric field is formed between the photosensitive member and the primary transfer bias roller due to the influence of the primary transfer bias.

Y用の感光体1Y上に形成された上述のYトナー像は、この一次転写電界やニップ圧の影響によって中間転写ベルト110上に一次転写される。このYトナー像の上には、M,C,K用の感光体1M,C,K上に形成されたM,C,Kトナー像が順次重ね合わせて一次転写される。この重ね合わせの一次転写により、中間転写ベルト110上には多重トナー像たる4色重ね合わせトナー像(以下、4色トナー像という)が形成される。   The above-described Y toner image formed on the Y photoconductor 1Y is primarily transferred onto the intermediate transfer belt 110 due to the influence of the primary transfer electric field and nip pressure. On the Y toner image, the M, C, K toner images formed on the M, C, K photoconductors 1M, C, K are sequentially superposed and primarily transferred. By this primary transfer of superposition, a four-color superposed toner image (hereinafter referred to as a four-color toner image) that is a multiple toner image is formed on the intermediate transfer belt 110.

中間転写ベルト110上に重ね合わせ転写された4色トナー像は、後述の二次転写ニップで記録体たる転写紙に二次転写される。二次転写ニップ通過後の中間転写ベルト110の表面に残留する転写残トナーは、図1中左側の駆動ローラ15との間にベルトを挟み込むベルトクリーニング装置90によってクリーニングされる。   The four-color toner image superimposed and transferred on the intermediate transfer belt 110 is secondarily transferred onto a transfer sheet as a recording medium at a secondary transfer nip described later. Transfer residual toner remaining on the surface of the intermediate transfer belt 110 after passing through the secondary transfer nip is cleaned by a belt cleaning device 90 that sandwiches the belt with the driving roller 15 on the left side in FIG.

次に、二次転写装置22について説明する。
中間転写ユニット17の図中下方には、2本の張架ローラ23によって紙搬送ベルト24を張架している二次転写装置22が配設されている。紙搬送ベルト24は、少なくとも何れか一方の張架ローラ23の回転駆動に伴って、図1中反時計回りに無端移動せしめられる。
Next, the secondary transfer device 22 will be described.
Below the intermediate transfer unit 17 in the figure, a secondary transfer device 22 is disposed in which a paper conveying belt 24 is stretched by two stretching rollers 23. The paper transport belt 24 is moved endlessly in the counterclockwise direction in FIG. 1 in accordance with the rotational drive of at least one of the stretching rollers 23.

2本の張架ローラ23のうち、図1中右側に配設された一方のローラは、中間転写ユニット17の二次転写バックアップローラ16との間に、中間転写ベルト110及び紙搬送ベルト24を挟み込んでいる。この挟み込みにより、中間転写ユニット17の中間転写ベルト110と、二次転写装置22の紙搬送ベルト24とが接触する二次転写ニップが形成されている。   One of the two stretching rollers 23, which is arranged on the right side in FIG. 1, has the intermediate transfer belt 110 and the paper transport belt 24 between the secondary transfer backup roller 16 of the intermediate transfer unit 17. It is sandwiched. By this sandwiching, a secondary transfer nip is formed in which the intermediate transfer belt 110 of the intermediate transfer unit 17 and the paper transport belt 24 of the secondary transfer device 22 are in contact with each other.

そして、この一方の張架ローラ23には、トナーと逆極性の二次転写バイアスが電源によって印加される。この二次転写バイアスの印加により、二次転写ニップには中間転写ユニット17の中間転写ベルト110上の4色トナー像をベルト側からこの一方の張架ローラ23側に向けて静電移動させる二次転写電界が形成される。   A secondary transfer bias having a polarity opposite to that of the toner is applied to the one stretching roller 23 by a power source. By applying this secondary transfer bias, the four-color toner image on the intermediate transfer belt 110 of the intermediate transfer unit 17 is electrostatically moved from the belt side toward the one stretching roller 23 side in the secondary transfer nip. A next transfer electric field is formed.

後述のレジストローラ対49によって中間転写ベルト110上の4色トナー像に同期するように二次転写ニップに送り込まれた転写紙には、この二次転写電界やニップ圧の影響を受けた4色トナー像が二次転写せしめられる。   The transfer paper fed into the secondary transfer nip so as to synchronize with the four-color toner image on the intermediate transfer belt 110 by a registration roller pair 49 to be described later has four colors affected by the secondary transfer electric field and nip pressure. The toner image is secondarily transferred.

なお、このように一方の張架ローラ23に二次転写バイアスを印加する二次転写方式に代えて、転写紙を非接触でチャージさせるチャージャを設けてもよい。   Instead of the secondary transfer method in which the secondary transfer bias is applied to one of the stretching rollers 23 as described above, a charger for charging the transfer paper in a non-contact manner may be provided.

複写機本体の下部に設けられた給紙装置200には、内部に複数の転写紙を紙束の状態で複数枚重ねて収容可能な給紙カセット44が、鉛直方向に複数重なるように配設されている。   In the paper feeding device 200 provided at the lower part of the copying machine main body, a plurality of paper feeding cassettes 44 in which a plurality of transfer sheets can be stacked and accommodated in a bundle of sheets are arranged so as to overlap in the vertical direction. Has been.

それぞれの給紙カセット44は、紙束の一番上の転写紙に給紙ローラ42を押し当てている。そして、給紙ローラ42を回転させることにより、一番上の転写紙を給紙路46に向けて送り出される。   Each paper feed cassette 44 presses the paper feed roller 42 against the uppermost transfer paper in the paper bundle. Then, by rotating the paper feed roller 42, the uppermost transfer paper is sent out toward the paper feed path 46.

給紙カセット44から送り出された転写紙を受け入れる給紙路46は、複数の搬送ローラ対47と、その路内の末端付近に設けられたレジストローラ対49とを有している。そして、転写紙をレジストローラ対49に向けて搬送する。レジストローラ対49に向けて搬送された転写紙は、レジストローラ対49のローラ間に挟まれる。   The paper feed path 46 that receives the transfer paper fed from the paper feed cassette 44 has a plurality of conveying roller pairs 47 and a registration roller pair 49 provided near the end in the path. Then, the transfer paper is conveyed toward the registration roller pair 49. The transfer sheet conveyed toward the registration roller pair 49 is sandwiched between the rollers of the registration roller pair 49.

一方、中間転写ユニット17において、中間転写ベルト110上に形成された4色トナー像は、ベルトの無端移動に伴って上記二次転写ニップに進入する。レジストローラ対49は、ローラ間に挟み込んだ転写紙を二次転写ニップにて4色トナー像に密着させ得るタイミングで送り出す。これにより、二次転写ニップでは、中間転写ベルト110上の4色トナー像が転写紙に密着する。そして、転写紙上に二次転写されて、白色の転写紙上でフルカラー画像となる。   On the other hand, in the intermediate transfer unit 17, the four-color toner image formed on the intermediate transfer belt 110 enters the secondary transfer nip as the belt moves endlessly. The registration roller pair 49 sends out the transfer paper sandwiched between the rollers at a timing at which the transfer paper can be brought into close contact with the four-color toner image at the secondary transfer nip. Thereby, in the secondary transfer nip, the four-color toner image on the intermediate transfer belt 110 is in close contact with the transfer paper. Then, it is secondarily transferred onto the transfer paper and becomes a full color image on the white transfer paper.

このようにしてフルカラー画像が形成された転写紙は、紙搬送ベルト24の無端移動に伴って二次転写ニップを出た後、紙搬送ベルト24上から定着装置25に送られる。   The transfer paper on which the full-color image is formed in this manner exits the secondary transfer nip as the paper transport belt 24 moves endlessly, and then is sent from the paper transport belt 24 to the fixing device 25.

定着装置25は、定着ベルト26を2本のローラによって張架しながら無端移動せしめるベルトユニットと、このベルトユニットの一方のローラに向けて押圧される加圧ローラ27とを備えている。   The fixing device 25 includes a belt unit that moves the fixing belt 26 endlessly while being stretched by two rollers, and a pressure roller 27 that is pressed toward one roller of the belt unit.

これら定着ベルト26と加圧ローラ27とは互いに当接して定着ニップを形成しており、紙搬送ベルト24から受け取った転写紙をここに挟み込む。   The fixing belt 26 and the pressure roller 27 are in contact with each other to form a fixing nip, and the transfer paper received from the paper transport belt 24 is sandwiched therebetween.

ベルトユニットにおける2本のローラのうち、加圧ローラ27から押圧される方のローラは、内部に熱源を有しており、これの発熱によって定着ベルト26を加圧する。加圧された定着ベルト26は、定着ニップに挟み込まれた転写紙を加熱する。この加熱やニップ圧の影響により、フルカラー画像が転写紙に定着せしめられる。   Of the two rollers in the belt unit, the roller that is pressed from the pressure roller 27 has a heat source therein, and pressurizes the fixing belt 26 by the heat generated by the heat source. The pressed fixing belt 26 heats the transfer paper sandwiched in the fixing nip. The full color image is fixed on the transfer paper by the influence of the heating and the nip pressure.

定着装置25内で定着処理が施された転写紙は、プリンタ筐体の図中左側板の外側に設けたスタック部57上にスタックされるか、もう一方の面にもトナー像を形成するために上述の二次転写ニップに戻されるかする。   The transfer paper subjected to the fixing process in the fixing device 25 is stacked on the stack portion 57 provided outside the left side plate in the drawing of the printer housing, or forms a toner image on the other surface. To the secondary transfer nip described above.

原稿のコピーがとられる際には、例えばシート原稿の束が原稿自動搬送装置400の原稿台30上セットされる。   When a document is copied, for example, a bundle of sheet documents is set on the document table 30 of the automatic document feeder 400.

ただし、その原稿が本状に閉じられている片綴じ原稿である場合には、コンタクトガラス32上にセットされる。このセットに先立ち、複写機本体に対して原稿自動搬送装置400が開かれ、スキャナ300のコンタクトガラス32が露出される。この後、閉じられた原稿自動搬送装置400によって片綴じ原稿が押さえられる。   However, when the original is a single-sided original that is closed in a main form, it is set on the contact glass 32. Prior to this setting, the automatic document feeder 400 is opened with respect to the copying machine main body, and the contact glass 32 of the scanner 300 is exposed. Thereafter, the single-bound original is pressed by the closed automatic document feeder 400.

このようにして原稿がセットされた後、コピースタートスイッチが押下されると、スキャナ300による原稿読取動作がスタートする。   When the copy start switch is pressed after the document is set in this way, the document reading operation by the scanner 300 starts.

ただし、原稿自動搬送装置400にシート原稿がセットされた場合には、この原稿読取動作に先立って、原稿自動搬送装置400がシート原稿をコンタクトガラス32まで自動移動させる。   However, when a sheet document is set on the automatic document feeder 400, the automatic document feeder 400 automatically moves the sheet document to the contact glass 32 prior to the document reading operation.

原稿読取動作では、まず、第一走行体33と第二走行体34とがともに走行を開始し、第一走行体33に設けられた光源から光が発射される。そして、原稿面からの反射光が第二走行体34内に設けられたミラーによって反射せしめられ、結像レンズ35を通過した後、読取センサ36に入射される。読取センサ36は、入射光に基づいて画像情報を構築する。   In the document reading operation, first, the first traveling body 33 and the second traveling body 34 both start traveling, and light is emitted from a light source provided in the first traveling body 33. Then, the reflected light from the document surface is reflected by a mirror provided in the second traveling body 34, passes through the imaging lens 35, and then enters the reading sensor 36. The reading sensor 36 constructs image information based on the incident light.

このような原稿読取動作と並行して、各プロセスカートリッジ18Y,M,C,K内の各機器や、中間転写ユニット17、二次転写装置22、定着装置25がそれぞれ駆動を開始する。   In parallel with such a document reading operation, each device in each of the process cartridges 18Y, 18M, 18C, 18K, the intermediate transfer unit 17, the secondary transfer device 22, and the fixing device 25 starts driving.

そして、読取センサ36によって構築された画像情報に基づいて、光書込ユニット21が駆動制御されて、各感光体1Y,M,C,K上に、Y,M,C,Kトナー像が形成される。これらトナー像は、中間転写ベルト110上に重ね合わせ転写された4色トナー像となる。   Based on the image information constructed by the reading sensor 36, the optical writing unit 21 is driven and controlled, and Y, M, C, and K toner images are formed on the respective photoreceptors 1Y, 1M, 1C, and 1K. Is done. These toner images become four-color toner images superimposed and transferred on the intermediate transfer belt 110.

また、原稿読取動作の開始とほぼ同時に、給紙装置200内では給紙動作が開始される。この給紙動作では、給紙ローラ42の1つが選択回転せしめられ、ペーパーバンク43内に多段に収容される給紙カセット44の1つから転写紙が送り出される。送り出された転写紙は、分離ローラ45で1枚ずつ分離されて給紙路46に進入した後、搬送ローラ対47によって二次転写ニップに向けて搬送される。   Further, almost simultaneously with the start of the document reading operation, the paper feeding operation is started in the paper feeding device 200. In this paper feeding operation, one of the paper feeding rollers 42 is selectively rotated, and the transfer paper is sent out from one of the paper feeding cassettes 44 accommodated in the paper bank 43 in multiple stages. The fed transfer paper is separated one by one by the separation roller 45 and enters the paper feed path 46, and is then transported toward the secondary transfer nip by the transport roller pair 47.

このような給紙カセット44からの給紙に代えて、手差しトレイ51からの給紙が行われる場合もある。この場合、手差し給紙ローラ50が選択回転せしめられて手差しトレイ51上の転写紙を送り出した後、分離ローラ52が転写紙を1枚ずつ分離してプリンタ部100の手差し給紙路53に給紙する。   In some cases, paper feeding from the manual feed tray 51 is performed instead of such paper feeding from the paper feeding cassette 44. In this case, after the manual feed roller 50 is selectively rotated to feed the transfer paper on the manual feed tray 51, the separation roller 52 separates the transfer paper one by one and feeds it to the manual feed path 53 of the printer unit 100. Make paper.

本複写機は、2色以上のトナーからなる他色画像を形成する場合には、中間転写ベルト110をその上部張架面がほぼ水平になる姿勢で張架して、上部張架面に全ての感光体1Y,M,C,Kを接触させる。   In the case of forming another color image composed of two or more colors of toner, the copying machine stretches the intermediate transfer belt 110 so that the upper stretched surface thereof is substantially horizontal, Photoconductors 1Y, 1M, 1C, and 1K are brought into contact with each other.

これに対し、Kトナーのみからなるモノクロ画像を形成する場合には、機構により、中間転写ベルト110を図中左下に傾けるような姿勢にして、その上部張架面をY,M,C用の感光体1Y,M,Cから離間させる。   On the other hand, when a monochrome image consisting of only K toner is formed, the mechanism is such that the intermediate transfer belt 110 is tilted to the lower left in the figure, and the upper stretched surface is used for Y, M, and C. Separated from the photoreceptors 1Y, 1M, 1C.

そして、4つの感光体1Y,M,C,Kのうち、K用の感光体1Kだけを図中反時計回りに回転させて、Kトナー像だけを作像する。この際、Y,M,Cについては、感光体1だけでなく、現像器も駆動を停止させて、感光体1や現像剤の不要な消耗を防止する。   Of the four photoconductors 1Y, 1M, 1C, and 1K, only the K photoconductor 1K is rotated counterclockwise in the drawing to form only the K toner image. At this time, for Y, M, and C, not only the photoreceptor 1 but also the developing device is stopped to prevent unnecessary consumption of the photoreceptor 1 and the developer.

本複写機は、複写機内の下記機器の制御を司るCPU等から構成される制御部と、液晶ディスプレイや各種キーボタン等などから構成される操作表示部とを備えている。   The present copying machine includes a control unit including a CPU that controls the following devices in the copying machine, and an operation display unit including a liquid crystal display, various key buttons, and the like.

操作者は、この操作表示部に対するキー入力操作により、制御部に対して命令を送ることで、転写紙の片面だけに画像を形成するモードである片面プリントモードについて、3つのモードの中から1つを選択することができる。この3つの片面プリントモードとは、ダイレクト排出モードと、反転排出モードと、反転デカール排出モードとからなる。   The operator sends a command to the control unit by a key input operation on the operation display unit, so that one of the three modes is selected from the three-sided print mode, which is a mode for forming an image only on one side of the transfer paper. You can choose one. The three single-sided printing modes include a direct discharge mode, a reverse discharge mode, and a reverse decal discharge mode.

図5は、現像装置4の概略構成を説明する概略断面図である。
図5に示すように、現像装置4の現像ケーシング440aは、アルミなどの金属材料により、第一仕切り壁133、第二仕切り壁134、放熱部120などが一体成形されたものである。また、現像ケーシング440aは、第二仕切り壁134と対向し、現像剤回収部たる回収搬送路7の回収壁440bも有している。この回収壁440bは、現像領域440cよりも現像スリーブ5aによる現像剤搬送方向下流側(以下、下流側という。)で現像スリーブの外表面と所定のギャップで対向し、現像スリーブ5a上の現像剤を現像ケーシング内に進入させるケーシングギャップGを形成している。現像ケーシング440aは、電気的に接地されている。
FIG. 5 is a schematic cross-sectional view illustrating a schematic configuration of the developing device 4.
As shown in FIG. 5, the developing casing 440a of the developing device 4 is formed by integrally forming a first partition wall 133, a second partition wall 134, a heat radiating portion 120, and the like with a metal material such as aluminum. The developing casing 440a also has a recovery wall 440b of the recovery transport path 7 that is opposed to the second partition wall 134 and is a developer recovery portion. The collection wall 440b is opposed to the outer surface of the developing sleeve with a predetermined gap on the downstream side in the developer conveying direction by the developing sleeve 5a (hereinafter referred to as downstream side) with respect to the developing region 440c, and the developer on the developing sleeve 5a. A casing gap G is formed to allow the toner to enter the developing casing. The developing casing 440a is electrically grounded.

現像装置4の現像領域440cでは、現像スリーブ5aの表面に担持された現像剤が一時的に現像ケーシング440aの外側へ搬送されることになる。現像剤は磁気力及び静電気力によって現像ローラ5の表面上に担持されており、現像領域440cを通過した後は、再び現像ケーシング内に回収される。   In the developing region 440c of the developing device 4, the developer carried on the surface of the developing sleeve 5a is temporarily conveyed to the outside of the developing casing 440a. The developer is carried on the surface of the developing roller 5 by magnetic force and electrostatic force, and after passing through the developing region 440c, it is collected again in the developing casing.

次に、本実施形態の特徴部である現像剤規制部材について説明する。
図6は、従来の現像装置における現像剤規制部材と現像ローラとを現像ローラの軸方向から見たときの説明図である。図7は、本実施形態の現像装置における現像剤規制部材と現像ローラとを現像ローラの軸方向から見たときの説明図である。
図6に示すように、現像ローラ5は、マグネットローラ5bが形成する複数の磁極によって、現像スリーブ5aの図6中時計周りの回転に伴って、現像剤を搬送する。従来の現像剤規制部材600は、現像スリーブ5aの外表面に対向して規制ギャップ(図6中Gd)を形成する規制端601aを有する、例えば非磁性部材の現像剤規制部材本体601と、現像剤規制部材本体601の現像スリーブ5aによる現像剤搬送方向上流側(以下、上流側という。)の側面に固定されている磁性部材602とを備えている。そして、現像スリーブ5aの外表面に対面する現像剤規制部材本体601の規制端601aが磁性部材602の先端部602aよりも現像ローラ5側に突出している。
Next, a developer regulating member that is a characteristic part of the present embodiment will be described.
FIG. 6 is an explanatory view of the developer regulating member and the developing roller in the conventional developing device as viewed from the axial direction of the developing roller. FIG. 7 is an explanatory diagram when the developer regulating member and the developing roller in the developing device of this embodiment are viewed from the axial direction of the developing roller.
As shown in FIG. 6, the developing roller 5 conveys the developer by a plurality of magnetic poles formed by the magnet roller 5b as the developing sleeve 5a rotates clockwise in FIG. A conventional developer regulating member 600 has a regulating end 601a that forms a regulating gap (Gd in FIG. 6) facing the outer surface of the developing sleeve 5a. And a magnetic member 602 fixed to the side surface on the upstream side (hereinafter referred to as the upstream side) in the developer conveying direction by the developing sleeve 5a of the agent regulating member main body 601. The regulating end 601a of the developer regulating member main body 601 that faces the outer surface of the developing sleeve 5a protrudes toward the developing roller 5 from the tip 602a of the magnetic member 602.

これに対し、本実施形態の現像剤規制部材700は、図6の従来の現像剤規制部材600に対し異なる構成として、図7に示すように、現像スリーブ5aによる現像剤搬送方向に対し直交する方向(軸線方向)から見たとき、現像剤規制部材本体701の規制端701aが、磁性部材702の先端部702cよりも上流側に位置するよう、現像剤規制部材本体701の先端部701cが磁性部材702の先端部702aと現像スリーブ5aの外表面との間を通って折れ曲がって磁性部材702の先端部702aよりも上流側に突出している形状をなしている。なお、本実施形態の現像剤規制部材の形状は本例のような形状でなくてもよい。例えば、現像剤規制部材の全体を下流側に斜めに倒し、かつ、現像剤規制部材本体の規制端が磁性部材の先端部よりも上流側に位置するよう、現像剤規制部材本体を現像スリーブ5aへ向けて突出させてもよい。   On the other hand, the developer regulating member 700 of the present embodiment is configured differently from the conventional developer regulating member 600 of FIG. 6, and is orthogonal to the developer conveying direction by the developing sleeve 5a as shown in FIG. When viewed from the direction (axial direction), the leading end 701c of the developer regulating member main body 701 is magnetic so that the regulating end 701a of the developer regulating member main body 701 is positioned upstream of the leading end 702c of the magnetic member 702. The member 702 is bent between the front end portion 702a of the developing sleeve 5a and the outer surface of the developing sleeve 5a so as to protrude upstream from the front end portion 702a of the magnetic member 702. Note that the shape of the developer regulating member of the present embodiment may not be the shape as in this example. For example, the developer regulating member main body is placed on the developing sleeve 5a so that the entire developer regulating member is tilted obliquely to the downstream side and the regulating end of the developer regulating member main body is positioned on the upstream side of the tip end portion of the magnetic member. You may make it protrude toward.

ここで、現像剤規制部材本体に対し磁性部材を取り付けたことによって現像スリーブ上の現像剤に対して働く現像スリーブ表面での接線方向成分をもつ磁気力(以下、接線方向磁気力という。)の変化について説明する。
図8は、図6及び図7の現像ローラ中心を原点とした時x(+)軸となす角度における現像スリーブ表面での接線方向磁気力変化を示すグラフである。図8(a)は、図6の従来の現像剤規制部材を所定の位置に配置したときの現像スリーブ表面での接線方向磁気力変化を示すグラフであり、図8(b)は、図7の本実施形態の現像装置における現像剤規制部材を所定の位置に配置したときの現像スリーブ表面での接線方向磁気力変化を示すグラフである。図8において、接線方向磁気力のプラスは、接線方向磁気力が現像剤に対し作用する向きが下流側であることを示し、逆にマイナスは接線方向磁気力が現像剤に対し作用する向きが上流側であることを示す。
Here, by attaching a magnetic member to the developer regulating member main body, a magnetic force having a tangential component on the surface of the developing sleeve acting on the developer on the developing sleeve (hereinafter referred to as a tangential magnetic force). The change will be described.
FIG. 8 is a graph showing a change in tangential magnetic force on the surface of the developing sleeve at an angle formed with the x (+) axis when the center of the developing roller in FIGS. 6 and 7 is the origin. FIG. 8A is a graph showing a tangential magnetic force change on the surface of the developing sleeve when the conventional developer regulating member of FIG. 6 is disposed at a predetermined position, and FIG. 8B is a graph showing FIG. 6 is a graph showing a tangential magnetic force change on the surface of the developing sleeve when the developer regulating member in the developing device of this embodiment is disposed at a predetermined position. In FIG. 8, a positive tangential magnetic force indicates that the direction in which the tangential magnetic force acts on the developer is downstream, and conversely, a negative indicates the direction in which the tangential magnetic force acts on the developer. Indicates upstream side.

一般に、現像装置では、現像スリーブ内部のマグネットローラにおける磁極による磁界の作用によって、接線方向磁気力が生じる。その接線方向磁気力の現像スリーブ上の現像剤に作用する向きが下流側へ向いていると、その作用の向きは現像スリーブの回転による現像剤搬送方向と同じであるので、現像剤の搬送は促進される。逆に、接線方向磁気力の作用の向きが上流側へ向いていると、その作用の向きは現像スリーブの回転による現像剤搬送方向と逆の向きであるので、現像剤の搬送を阻害してしまう。   Generally, in a developing device, a tangential magnetic force is generated by the action of a magnetic field by a magnetic pole in a magnet roller inside a developing sleeve. When the direction of the tangential magnetic force acting on the developer on the developing sleeve is directed to the downstream side, the direction of the action is the same as the developer conveying direction by the rotation of the developing sleeve. Promoted. Conversely, if the direction of the action of the tangential magnetic force is directed upstream, the direction of the action is opposite to the developer conveyance direction due to the rotation of the developing sleeve. End up.

現像剤規制部材に対向する現像スリーブ表面上の位置(以下、規制位置という。)近傍では、現像スリーブ上の現像剤に対して働く接線方向磁気力は、下流側に向かって次のように変化している。すなわち、規制位置に対し離れた上流側の現像スリーブ表面上のある位置から規制位置へ近づくほど、接線方向磁気力の現像剤に対し作用する向きは下流側へ向いているており、接線方向磁気力の強さは徐々に小さくなってくる。その後、接線方向磁気力の作用の向きは現像スリーブ表面上のある地点で上流側へ反転し、接線方向磁気力の強さは徐々に大きくなっていき、規制位置よりも下流側の地点で最大値となりその後徐々に小さくなる。   In the vicinity of a position on the surface of the developing sleeve facing the developer regulating member (hereinafter referred to as a regulating position), the tangential magnetic force acting on the developer on the developing sleeve changes as follows toward the downstream side. doing. That is, the closer to the restriction position from a certain position on the upstream developing sleeve surface far from the restriction position, the more the tangential magnetic force acts on the developer toward the downstream side. The strength of power gradually decreases. Thereafter, the direction of the action of the tangential magnetic force reverses to the upstream side at a certain point on the surface of the developing sleeve, and the strength of the tangential magnetic force gradually increases and reaches the maximum at a point downstream of the regulation position. And then gradually decreases.

図7の本実施形態の現像剤規制部材において、図6の従来の現像剤規制部材と同様に、現像剤規制部材本体に対し磁性部材を取り付けると、現像スリーブの外表面に最も近い現像剤規制部材本体の部分は磁性部材に対し下流側に位置されている。図8に示すような現像スリーブ5aの表面での接線方向磁気力は、磁性部材と現像スリーブ内のマグネットローラ5bとの間の磁界によって、図8に示すような波形に変わる。詳しくは、角度93度付近ではマイナスの接線方向磁気力の強さが最大値になり、角度100度付近ではプラスの接線方向磁気力の強さが最大値になる増減波形になる。その増減する接線方向磁気力の強さは、現像剤規制部材本体のみの現像剤規制部材の場合に比べて大きくなっている。そして、現像剤規制部材本体の先端部が対向する現像スリーブの外表面での接線方向磁気力の作用の向きが上流側へ向くような現像スリーブ表面上の位置で現像剤を規制している。このため、現像剤が規制ギャップを通過する向きとは逆の向きに現像剤に対し接線方向磁気力が働くことになり、現像剤が規制ギャップを通過する効率が悪化していた。   In the developer regulating member of the present embodiment in FIG. 7, when the magnetic member is attached to the developer regulating member main body, as in the conventional developer regulating member in FIG. 6, the developer regulating closest to the outer surface of the developing sleeve. The part of the member body is located on the downstream side with respect to the magnetic member. The tangential magnetic force on the surface of the developing sleeve 5a as shown in FIG. 8 changes to a waveform as shown in FIG. 8 by the magnetic field between the magnetic member and the magnet roller 5b in the developing sleeve. Specifically, a negative tangential magnetic force intensity has a maximum value near an angle of 93 degrees, and a positive tangential magnetic force intensity has a maximum value near an angle of 100 degrees. The strength of the increasing / decreasing tangential magnetic force is larger than in the case of the developer regulating member having only the developer regulating member main body. The developer is regulated at a position on the surface of the developing sleeve such that the direction of the action of the tangential magnetic force on the outer surface of the developing sleeve facing the tip of the developer regulating member main body is directed upstream. For this reason, a tangential magnetic force acts on the developer in a direction opposite to the direction in which the developer passes through the regulation gap, and the efficiency of the developer passing through the regulation gap is deteriorated.

また、図9に示す現像スリーブ表面での接線方向磁気力と現像剤搬送量低下率との関係を示すグラフからわかるように、現像スリーブ表面での接線方向磁気力と現像剤搬送量低下率との間には、線形の相関がある。図9の横軸は、現像スリーブ表面での接線方向磁気力[N]である。縦軸は、現像剤搬送量低下率ρ[%]であり、これは初期現像スリーブにより搬送される現像剤の量と、印字率5[%]の画像を1P/Jモードにおいて、70k枚印刷した後に現像スリーブ5aにより搬送される現像剤の量との比率を示す。具体的には、以下式で求める。現像剤搬送量低下率ρ[%]=100−(複写機をある程度使用した後に現像スリーブにより搬送される現像剤の量)/(初期現像スリーブにより搬送される現像剤の量)×100   Further, as can be seen from the graph showing the relationship between the tangential magnetic force on the developing sleeve surface and the developer conveyance amount decrease rate shown in FIG. 9, the tangential magnetic force on the developing sleeve surface and the developer conveyance amount decrease rate There is a linear correlation between. The horizontal axis in FIG. 9 is the tangential magnetic force [N] on the surface of the developing sleeve. The vertical axis represents the developer conveyance amount decrease rate ρ [%]. This is the amount of the developer conveyed by the initial developing sleeve and the image with a printing rate of 5 [%] is printed in 70k sheets in the 1P / J mode. The ratio with the amount of the developer conveyed by the developing sleeve 5a is shown. Specifically, the following formula is used. Developer transport amount decrease rate ρ [%] = 100− (amount of developer transported by developing sleeve after using copy machine to some extent) / (amount of developer transported by initial developing sleeve) × 100

そして、図9のプロット点Aは、図6において現像ローラ5の中心5cと現像剤規制部材本体601の規制端601aとを結んだ仮想線601bと現像スリーブ5aの外表面とが交わる地点5cでの接線方向磁気力を示す。図9のプロット点Bとプロット点Cとは、図7において現像ローラ5の中心5cと現像剤規制部材本体701の規制端701aとを結んだ仮想線701bと現像スリーブ5aの外表面とが交わる地点5eでの接線方向磁気力を示す。図9のプロット点Aは、接線方向磁気力について、その磁気力が現像スリーブ上の現像剤に対し作用する方向の向きがマイナス、すなわち上流側に向き、かつ、現像剤搬送量低下率が図9のプロット点B及びプロット点Cよりも高くなることが判明した。これに対し、図9のプロット点B及びプロット点Cは、接線方向磁気力について、その磁気力が現像スリーブ上の現像剤に対し作用する方向の向きがプラス、すなわち下流側に向き、かつ、現像剤搬送量低下率は図9のプロット点Aよりも低くなることが判明した。   A plot point A in FIG. 9 is a point 5c where an imaginary line 601b connecting the center 5c of the developing roller 5 and the regulating end 601a of the developer regulating member main body 601 in FIG. 6 intersects the outer surface of the developing sleeve 5a. The tangential magnetic force of Plot point B and plot point C in FIG. 9 intersect the imaginary line 701b connecting the center 5c of the developing roller 5 and the regulating end 701a of the developer regulating member main body 701 in FIG. 7 with the outer surface of the developing sleeve 5a. The tangential magnetic force at the point 5e is shown. Plot point A in FIG. 9 shows the tangential magnetic force in the direction in which the magnetic force acts on the developer on the developing sleeve is negative, that is, in the upstream direction, and the developer conveyance amount decrease rate is illustrated. It was found that the plot points B and C were higher than 9 plot points B and C. On the other hand, the plot point B and plot point C in FIG. 9 indicate that the direction of the magnetic force acting on the developer on the developing sleeve is positive, that is, the downstream direction, with respect to the tangential magnetic force. It has been found that the rate of decrease in the developer conveyance amount is lower than the plot point A in FIG.

図9に示すように、現像スリーブ5a表面での接線方向磁気力と現像剤搬送量低下率は線形の相関があり、現像スリーブ5a表面での接線方向磁気力についてその値がマイナスで強さ(絶対値)が大きくなるほど、現像剤搬送量低下率が高まる。その結果、例えば現像剤の劣化が進むと現像剤に含まれる添加剤が磁性キャリアに付着して現像剤の流動性が落ちる。現像スリーブ表面に対し遠い現像剤の上部について、現像剤の流動性が高めであれば、低い現像剤の搬送力でも現像スリーブ表面に対し近い現像剤下部と一緒に現像スリーブの回転移動に対し追従できるのに対し、現像剤の流動性が落ちると、同じ低い現像剤の搬送力であっても現像スリーブ表面に対し近い現像剤下部と一緒には現像スリーブの回転移動に対して追従し難くなる。この結果、現像剤が規制ギャップ(Gd)を通過し難くなるので、規制ギャップ(Gd)を通過する現像剤量が減り、経時による現像領域への現像剤搬送量が低下してしまう。   As shown in FIG. 9, the tangential magnetic force on the surface of the developing sleeve 5a and the developer conveyance amount decrease rate have a linear correlation, and the value of the tangential magnetic force on the surface of the developing sleeve 5a is negative and strong ( As the absolute value increases, the rate of decrease in the developer conveyance amount increases. As a result, for example, when the developer deteriorates, the additive contained in the developer adheres to the magnetic carrier, and the fluidity of the developer decreases. If the developer fluidity is high at the upper part of the developer far from the surface of the developing sleeve, the developer sleeve can follow the rotational movement of the developing sleeve together with the lower part of the developer close to the developing sleeve surface even with a low developer conveying force. On the other hand, when the flowability of the developer is lowered, it becomes difficult to follow the rotational movement of the developing sleeve together with the lower part of the developer that is close to the developing sleeve surface even with the same low developer conveying force. . As a result, it becomes difficult for the developer to pass through the regulation gap (Gd), so the amount of developer passing through the regulation gap (Gd) is reduced, and the amount of developer transported to the development area with time is reduced.

これに対し、現像スリーブ5a表面での接線方向磁気力についてその値がプラスで強さ(絶対値)が大きくなるほど、現像剤搬送量低下率が低下する。その結果、例えば現像剤の劣化が進んで現像剤の流動性が落ちても、現像剤搬送力が低下していないので、現像剤担持体表面に対し近い現像剤下部と一緒に現像剤担持体表面に対し遠い現像剤上部も、現像剤担持体の回転移動に対して追従させることができる。これにより、規制ギャップ(Gd)を通過する現像剤の狙いの部分で規制され易くなって、規制された現像剤は狙いの量になる。よって、経時による現像領域への現像剤搬送量の低下を抑制することができる。   On the other hand, as the value of the tangential magnetic force on the surface of the developing sleeve 5a increases and the strength (absolute value) increases, the rate of decrease in the developer conveyance amount decreases. As a result, for example, even if the developer is deteriorated and the fluidity of the developer is lowered, the developer conveying force is not lowered. Therefore, the developer carrying body together with the lower part of the developer close to the surface of the developer carrying body. The upper part of the developer far from the surface can also follow the rotational movement of the developer carrier. Thereby, it becomes easy to be regulated at the target portion of the developer that passes through the regulation gap (Gd), and the regulated developer becomes the target amount. Therefore, it is possible to suppress a decrease in the developer conveyance amount to the development area over time.

従来の現像剤規制部材では、図8(a)に示すように、図6において現像ローラ5の中心5cと現像剤規制部材本体601の規制端601aとを結んだ仮想線601bと現像スリーブ5aの外表面とが交わる地点5dでの接線方向磁気力が現像剤に対し作用する向きは上流側である。そして、現像剤規制部材本体601の規制端601aと現像スリーブ5aの外表面との間の規制ギャップ(Gd)が形成される規制位置近傍における現像スリーブ5aの外表面での接線方向磁気力の作用の向きが上流側へ向くような現像スリーブ表面上の位置で現像剤を規制しているので、現像剤が規制ギャップ(Gd)を通過する向きとは逆の向きに現像剤に対し接線方向磁気力が働くことになり、現像剤が規制ギャップを通過する効率が悪化していた。そして、例えば経時により現像剤の劣化が進むと現像剤に含まれる添加剤が磁性キャリアに付着して現像剤の流動性が落ちる。その結果、現像剤が規制ギャップを通過し難くなるので、規制ギャップを通過する現像剤量は現像剤が劣化する前に比べて大幅に減る。これにより、経時による現像領域への現像剤搬送量が低下してしまう。   In the conventional developer regulating member, as shown in FIG. 8A, an imaginary line 601b connecting the center 5c of the developing roller 5 and the regulating end 601a of the developer regulating member main body 601 in FIG. 6 and the developing sleeve 5a. The direction in which the tangential magnetic force at the point 5d where the outer surface intersects the developer acts on the developer is upstream. The action of the tangential magnetic force on the outer surface of the developing sleeve 5a in the vicinity of the regulating position where the regulating gap (Gd) between the regulating end 601a of the developer regulating member main body 601 and the outer surface of the developing sleeve 5a is formed. Since the developer is regulated at a position on the surface of the developing sleeve so that the direction of the developer is directed upstream, the magnetic tangential to the developer is opposite to the direction in which the developer passes through the regulation gap (Gd). As a result, the efficiency of the developer passing through the regulation gap deteriorated. For example, when the deterioration of the developer progresses with time, the additive contained in the developer adheres to the magnetic carrier and the fluidity of the developer decreases. As a result, since it becomes difficult for the developer to pass through the regulation gap, the amount of the developer that passes through the regulation gap is greatly reduced as compared with that before the developer deteriorates. As a result, the amount of developer transported to the development area over time decreases.

これに対し、本実施形態の現像装置における現像剤規制部材では、図8(b)に示すように、図7において現像ローラ5の中心5cと現像剤規制部材本体701の規制端701aとを結んだ仮想線701bと現像スリーブ5aの外表面とが交わる地点5eでの接線方向磁気力が現像剤に対し作用する方向は下流側である。そして、接線方向磁気力の作用方向が下流側に向いている現像スリーブ5aの外表面の部分で、現像スリーブ5a上の現像剤を規制させる。これにより、現像剤規制部材本体701の規制端701aを有する先端部701cと現像スリーブの外表面との間の規制ギャップGdを通過しようとする力が現像剤に作用する。よって、この状態で、例えば経時により現像剤の劣化が進んで現像剤に含まれる添加剤が磁性キャリアに付着して現像剤の流動性が落ちても、接線方向磁気力の作用の向きが上流側に向いている現像スリーブ5aの外表面の部分に対向するよう現像剤規制部材本体の規制端を配置した従来の構成に比べて、現像スリーブ5aの回転に対する追従性は高まる。その結果、規制ギャップに搬送された現像剤の現像スリーブ5aに近い下部や遠い上部も規制ギャップを現像スリーブ5aの回転に追従して通過するので、現像剤の狙いの部分を現像スリーブ5aの外表面に最も近い現像剤規制部材本体の規制端で規制することができ、規制ギャップを通過した現像剤量は狙いの量になる。よって、経時による現像領域への現像剤搬送量の低下を抑制することができる。   On the other hand, in the developer regulating member in the developing device of this embodiment, as shown in FIG. 8B, the center 5c of the developing roller 5 and the regulating end 701a of the developer regulating member main body 701 are connected in FIG. The direction in which the tangential magnetic force acts on the developer at the point 5e where the virtual line 701b and the outer surface of the developing sleeve 5a intersect is downstream. Then, the developer on the developing sleeve 5a is regulated at a portion of the outer surface of the developing sleeve 5a in which the acting direction of the tangential magnetic force is directed to the downstream side. As a result, a force that attempts to pass through the regulating gap Gd between the tip end portion 701c having the regulating end 701a of the developer regulating member main body 701 and the outer surface of the developing sleeve acts on the developer. Therefore, in this state, for example, even if the developer deteriorates with time and the additive contained in the developer adheres to the magnetic carrier and the fluidity of the developer decreases, the direction of the tangential magnetic force acts upstream. Compared with the conventional configuration in which the regulating end of the developer regulating member main body is disposed so as to face the outer surface portion of the developing sleeve 5a facing the side, the followability to the rotation of the developing sleeve 5a is enhanced. As a result, the lower part of the developer conveyed to the regulation gap and the upper part far from the development sleeve 5a also pass through the regulation gap following the rotation of the development sleeve 5a, so that the target portion of the developer is outside the development sleeve 5a. The developer can be regulated by the regulating end of the developer regulating member main body closest to the surface, and the amount of developer that has passed through the regulating gap becomes the target amount. Therefore, it is possible to suppress a decrease in the developer conveyance amount to the development area over time.

ここで、図9のプロット点Aを示した第1の現像剤規制部材(図6に示す従来の現像剤規制部材600)、図9のプロット点B及びプロット点Cを示した第2、第3の現像剤規制部材(図7に示す本実施形態の現像剤規制部材700)を現像装置に搭載し、初期時と、印字率5[%]の画像を1P/Jモードにおいて、70k枚印字した後のベタ画像濃度の確認を行った。この結果、第1の現像剤規制部材を現像剤に搭載した場合は、現像剤搬送量の低下により、20[%]以上の画像濃度変動があったのに対して、第2、第3の現像剤規制部材を現像装置に搭載した場合は、20[%]以下の濃度変動におさまり、実使用上問題ないレベルとなった。   Here, the first developer regulating member (conventional developer regulating member 600 shown in FIG. 6) showing the plot point A in FIG. 9, the second and second plots showing the plot points B and C in FIG. No. 3 developer regulating member (developer regulating member 700 of the present embodiment shown in FIG. 7) is mounted on the developing device, and 70k sheets are printed at the initial time and at a printing rate of 5% in 1P / J mode. After that, the solid image density was confirmed. As a result, when the first developer regulating member is mounted on the developer, the image density variation of 20 [%] or more was caused by the decrease in the developer conveyance amount, whereas the second and third When the developer regulating member was mounted on the developing device, the density fluctuation was 20% or less, and the level was not problematic in actual use.

次に、本実施形態に係る現像装置における現像剤規制部材の別の構成例について説明する。
図10(a)は、図7の現像剤規制部材が撓んでいないとき上方から見た説明図である。図10(b)は、図7の現像剤規制部材が撓んだとき上方から見た説明図である。図11(a)は、別の構成例の現像剤規制部材が撓んでいないとき上方から見た説明図である。図11(b)は、別の構成例の現像剤規制部材が撓んだとき上方から見たときの説明図である。図12は、別の構成例の現像剤規制部材の幅方向における中央部が撓む前の中央部及び両端部の現像スリーブ表面での接線方向磁気力変化を示すグラフである。図13は、別の構成例の現像剤規制部材の幅方向における中央部が撓んだ後の中央部及び両端部の現像スリーブ表面での接線方向磁気力変化を示すグラフである。
Next, another configuration example of the developer regulating member in the developing device according to the present embodiment will be described.
FIG. 10A is an explanatory diagram viewed from above when the developer regulating member of FIG. 7 is not bent. FIG. 10B is an explanatory view seen from above when the developer regulating member of FIG. 7 is bent. FIG. 11A is an explanatory diagram viewed from above when the developer regulating member of another configuration example is not bent. FIG. 11B is an explanatory diagram when viewed from above when the developer regulating member of another configuration example is bent. FIG. 12 is a graph showing changes in the tangential magnetic force on the surface of the developing sleeve at the central portion and both ends before the central portion in the width direction of the developer regulating member of another configuration example is bent. FIG. 13 is a graph showing changes in the tangential magnetic force on the surface of the developing sleeve at the central portion and both ends after the central portion in the width direction of the developer regulating member of another configuration example is bent.

図10に示す現像剤規制部材700は、軸線方向における両端部でビス等によって現像装置のケーシング等に固定されている。その現像剤規制部材700の規制磁極に対する位置は、図10(a)に示すように、現像前では現像剤規制部材700の現像剤搬送方向に直交する方向(以下、幅方向という。)における中央部と両端部とで互いに同じである。そして、現像が開始されると、現像剤が現像スリーブの表面移動によって下流側の方向(図10(b)中の矢印で示す方向)へ移動する。   A developer regulating member 700 shown in FIG. 10 is fixed to a casing or the like of the developing device with screws or the like at both ends in the axial direction. The position of the developer regulating member 700 with respect to the regulating magnetic pole is, as shown in FIG. 10A, the center in the direction (hereinafter referred to as the width direction) orthogonal to the developer conveying direction of the developer regulating member 700 before development. The part and both end parts are the same. When the development is started, the developer moves in the downstream direction (the direction indicated by the arrow in FIG. 10B) due to the surface movement of the developing sleeve.

その移動してくる現像剤は、現像剤規制部材本体701の上流側の側面(規制面)によって堰き止められる。その規制面には、現像剤による圧力が加わる。その結果、現像剤規制部材本体701の幅方向における中央部701dは、下流側へ撓む。一方、現像剤規制部材本体701の幅方向における両端部701eは、現像装置のケーシング等に固定されているので、現像剤による圧力が加えられてもほとんど撓まない。   The moving developer is blocked by the upstream side surface (regulating surface) of the developer regulating member main body 701. The pressure by the developer is applied to the regulation surface. As a result, the center portion 701d in the width direction of the developer regulating member main body 701 bends to the downstream side. On the other hand, since both end portions 701e in the width direction of the developer regulating member main body 701 are fixed to the casing of the developing device or the like, they hardly bend even when pressure is applied by the developer.

その結果、現像剤規制部材700の規制磁極に対する位置について、現像剤規制部材700の幅方向における中央部と両端部とでは互いに異なってしまう。それにより、現像剤規制部材本体701の規制位置近傍における現像スリーブの外表面での接線方向磁気力の現像スリーブ上の現像剤に対し作用する強さが、幅方向における中央部と両端部とで異なってしまう。その結果、現像剤規制部材本体701の幅方向における中央部701dと両端部701eとの間で現像剤に作用する搬送力に差が生じる。そのため、規制ギャップを通過する現像剤の通過量について、現像剤規制部材本体701の幅方向における中央部701dと両端部701eとの間で差が生じる。よって、規制ギャップを通過する現像剤について現像スリーブの軸線方向で不均一になり、それが画像濃度ムラの原因となっていた。   As a result, the position of the developer restricting member 700 with respect to the restricting magnetic pole differs between the central portion and both end portions in the width direction of the developer restricting member 700. As a result, the strength of the tangential magnetic force on the outer surface of the developing sleeve in the vicinity of the regulating position of the developer regulating member main body 701 acting on the developer on the developing sleeve is reduced at the center and both ends in the width direction. It will be different. As a result, a difference occurs in the transport force acting on the developer between the center portion 701d and both end portions 701e in the width direction of the developer regulating member main body 701. Therefore, a difference occurs between the central portion 701d and both end portions 701e in the width direction of the developer regulating member main body 701 with respect to the amount of developer passing through the regulating gap. Therefore, the developer passing through the regulation gap becomes non-uniform in the axial direction of the developing sleeve, which causes uneven image density.

そこで、別の構成例の現像剤規制部材700では、図11(a)に示すように、現像剤規制部材本体701の幅方向における中央部701dの先端部が、幅方向における両端部701eの先端部よりも現像スリーブによる現像剤搬送方向上流側へ延伸している。現像剤規制部材本体701の幅方向における中央部701dの先端部と、磁性部材702の現像剤規制部材本体701との接合部との間の距離をW1とし、現像剤規制部材本体701の幅方向における両端部701eの先端部と、磁性部材702の現像剤規制部材本体701との接合部との間の距離をW2とする。別の構成例の現像剤規制部材700では、現像前、W1>W2となっている。なお、現像剤規制部材本体701の幅方向における中央部701dを両端部701eよりも延伸させる延伸量(=W1−W2)は、予め、現像剤規制部材本体701の幅方向における中央部701dの撓み量に応じて調整可能である。   Therefore, in the developer regulating member 700 of another configuration example, as shown in FIG. 11A, the distal end portion of the central portion 701d in the width direction of the developer regulating member main body 701 is the distal end of both end portions 701e in the width direction. It extends to the upstream side of the developer conveying direction by the developing sleeve from the portion. The distance between the tip of the central portion 701d in the width direction of the developer regulating member main body 701 and the joint between the magnetic member 702 and the developer regulating member main body 701 is W1, and the width direction of the developer regulating member main body 701 is set. The distance between the tip of both end portions 701e and the joint between the magnetic member 702 and the developer regulating member main body 701 is W2. In the developer regulating member 700 of another configuration example, W1> W2 before development. Note that the amount of stretching (= W1−W2) by which the center portion 701d in the width direction of the developer regulating member main body 701 is stretched more than the both end portions 701e is the deflection of the center portion 701d in the width direction of the developer regulating member main body 701 in advance. It can be adjusted according to the amount.

そして、現像時、現像剤が現像スリーブの表面移動によって現像スリーブによる現像剤搬送方向下流側の方向(図11(b)中の矢印で示す方向)へ移動してくると、その現像剤は現像剤規制部材本体701の規制面によって堰き止められる。その規制面には、現像剤による圧力が加わる。現像剤規制部材本体701の幅方向における中央部701dは、現像剤規制部材本体701の幅方向における両端部701eによりも下流側へ撓む。なお、図12に示すように、現像剤規制部材700の規制磁極に対する位置(角度位置)は、現像剤規制部材700の幅方向における中央部701dと両端部701eとで互いに異なっている。そして、現像剤規制部材本体701の幅方向における中央部701dに対面する現像スリーブの外表面での接線方向磁気力の現像スリーブ上の現像剤に対し作用する強さは、両端部701eによりも低くなっている。   During development, when the developer moves in the direction downstream of the developer conveying direction by the developing sleeve due to the surface movement of the developing sleeve (the direction indicated by the arrow in FIG. 11B), the developer is developed. It is dammed by the regulating surface of the agent regulating member main body 701. The pressure by the developer is applied to the regulation surface. A central portion 701d in the width direction of the developer regulating member main body 701 is bent further downstream by both end portions 701e in the width direction of the developer regulating member main body 701. As shown in FIG. 12, the position (angular position) of the developer restricting member 700 with respect to the restricting magnetic pole is different between the central portion 701d and both end portions 701e in the width direction of the developer restricting member 700. Then, the strength of the tangential magnetic force on the outer surface of the developing sleeve facing the central portion 701d in the width direction of the developer regulating member main body 701 acting on the developer on the developing sleeve is lower than at both end portions 701e. It has become.

その結果、現像スリーブによる現像剤搬送方向に対し直交する軸線方向から見たとき、現像スリーブの外表面に最も近い現像剤規制部材本体701の部分を有する先端部について、現像剤規制部材本体701の幅方向における中央部701dは、図11(b)に示すように、当該中央部が現像時に下流側へ撓んだとき、現像剤規制部材本体701の幅方向における両端部701eとほぼ同じ位置になる。   As a result, when viewed from the axial direction perpendicular to the developer conveying direction by the developing sleeve, the tip of the developer regulating member main body 701 having the portion of the developer regulating member main body 701 closest to the outer surface of the developing sleeve. As shown in FIG. 11B, the center portion 701d in the width direction is located at substantially the same position as both end portions 701e in the width direction of the developer regulating member main body 701 when the center portion is bent downstream during development. Become.

そして、このとき、現像剤規制部材700の規制磁極に対する位置(角度位置)は、図13に示すように、現像剤規制部材700の幅方向における中央部701dと両端部701eとで互いに略同じとなっている。その結果、現像剤規制部材本体701の規制位置近傍における現像スリーブの外表面での接線方向磁気力の現像スリーブ上の現像剤に対し作用する向きや強さについても、現像剤担持体の軸線方向における中央部と両端部とで互いに略同じになる。これにより、規制ギャップを通過する現像剤の通過量は、現像剤規制部材本体701の幅方向における中央部701dと両端部701eとの差がほぼなくなる。これにより、規制ギャップを通過する現像剤について現像スリーブの軸線方向でほぼ均一になり、現像剤規制部材700の撓みによる画像濃度ムラを抑制することができる。また、現像スリーブ表面での接線方向磁気力の変化が、現像スリーブの軸線方向における箇所で異なることがわかった。そこで、接線方向磁気力の現像スリーブ上の現像剤に対し作用する向きが下流側へ向いているよう、現像剤規制部材本体701の幅方向における先端部の延伸量を変え、規制ギャップを通過する現像剤について現像スリーブの軸線方向でほぼ均一にする。これにより、現像剤規制部材700の撓みによる画像濃度ムラを抑制することができる。   At this time, the position (angular position) of the developer restricting member 700 with respect to the restricting magnetic pole is substantially the same at the center portion 701d and both end portions 701e in the width direction of the developer restricting member 700, as shown in FIG. It has become. As a result, the direction and strength of the tangential magnetic force on the outer surface of the developing sleeve in the vicinity of the regulating position of the developer regulating member main body 701 acting on the developer on the developing sleeve is also the axial direction of the developer carrying member. The central portion and both end portions of the are substantially the same. As a result, the amount of developer passing through the regulation gap is almost the same as the difference between the central portion 701d and the both end portions 701e in the width direction of the developer regulating member main body 701. Thereby, the developer passing through the regulation gap becomes substantially uniform in the axial direction of the development sleeve, and image density unevenness due to the deflection of the developer regulation member 700 can be suppressed. Further, it has been found that the change in the tangential magnetic force on the surface of the developing sleeve differs depending on the position in the axial direction of the developing sleeve. Therefore, the extension amount of the tip in the width direction of the developer regulating member main body 701 is changed so that the direction of the tangential magnetic force acting on the developer on the developing sleeve is directed to the downstream side, and passes through the regulating gap. The developer is made almost uniform in the axial direction of the developing sleeve. Thereby, image density unevenness due to the bending of the developer regulating member 700 can be suppressed.

以上に説明したものは一例であり、次の態様毎に特有の効果を奏する。
(態様A)
マグネットローラ5b等の磁界発生手段を中空体内に配置し、該磁界発生手段の磁力により該中空体の外表面上に磁性キャリアとトナーとからなる二成分の現像剤を担持して自身が回転することでその現像剤を搬送する現像スリーブ5a等の現像剤担持体と、現像剤規制部材本体701等の非磁性部材と磁性部材702とからなり、かつ、該現像剤担持体上の現像剤の量を規制する現像剤規制部材700とを備え、磁性部材は非磁性部材に対し現像剤担持体による現像剤搬送方向上流側に設置させている現像装置4において、前記現像剤担持体の外表面での前記磁界発生手段による磁界によって前記現像剤担持体上の現像剤に対して働く接線方向成分の磁気力の前記現像剤担持体上の前記現像剤に対し作用する方向が前記現像剤担持体による現像剤搬送方向下流側に向いている前記現像剤担持体の外表面の部分に、前記現像剤担持体の外表面に最も近い前記非磁性部材の部分が対向している。
磁界発生手段の磁極による磁界によって生じている現像剤担持体表面での接線方向成分をもつ磁気力(以下、接線方向磁気力という。)の現像剤に対し作用する向きが、現像剤担持体による現像剤搬送方向下流側へ向いていると、その接線方向磁気力が作用している現像剤は、多少の搬送抵抗があっても現像剤担持体の回転に対して追従することができる。
本態様では、現像剤担持体の外表面に最も近い非磁性部材の部分が現像剤担持体の外表面に対向する位置では、接線方向磁気力の現像剤に対し作用する向きが、現像剤担持体による現像剤搬送方向下流側に向いている。その位置では、現像剤が現像剤担持体の外表面に最も近い非磁性部材の部分と現像剤担持体の外表面との間(以下、規制ギャップという。)を通過する方向に接線方向磁気力が働くことになり、現像剤の搬送が促進される。この結果、例えば経時により現像剤の劣化が進んで現像剤に含まれる添加剤が磁性キャリアに付着して現像剤の流動性が落ちて現像剤に対し多少の搬送抵抗が発生しても、その劣化した現像剤を現像剤担持体の回転に追従させて規制ギャップを通過させることができる。よって、現像領域への現像剤搬送量の経時による低下を抑制することができる。
What was demonstrated above is an example, and there exists an effect peculiar for every following aspect.
(Aspect A)
A magnetic field generating means such as a magnet roller 5b is disposed in the hollow body, and the two-component developer composed of a magnetic carrier and toner is carried on the outer surface of the hollow body by the magnetic force of the magnetic field generating means and rotates itself. The developer carrying member such as the developing sleeve 5a that conveys the developer, the non-magnetic member such as the developer regulating member main body 701, and the magnetic member 702, and the developer on the developer carrying member. A developer regulating member 700 that regulates the amount of the developer carrying member, and the magnetic member is installed upstream of the non-magnetic member in the developer carrying direction by the developer carrying member. The direction in which the magnetic force of the tangential component acting on the developer on the developer carrier is exerted on the developer on the developer carrier by the magnetic field generated by the magnetic field generating means in the developer carrier. by The portion of the outer surface of said developer carrying member facing the image agent downstream side closest portions of the non-magnetic member on an outer surface of said developer carrying member is opposed.
The direction of the magnetic force having a tangential component on the surface of the developer carrying member generated by the magnetic field generated by the magnetic pole of the magnetic field generating means (hereinafter referred to as tangential magnetic force) is applied to the developer by the developer carrying member. When the developer is directed downstream in the developer conveyance direction, the developer on which the tangential magnetic force acts can follow the rotation of the developer carrier even if there is some conveyance resistance.
In this aspect, at the position where the portion of the non-magnetic member closest to the outer surface of the developer carrying member faces the outer surface of the developer carrying member, the direction in which the tangential magnetic force acts on the developer is It faces the downstream side of the developer conveying direction by the body. At that position, the tangential magnetic force in the direction in which the developer passes between the portion of the non-magnetic member closest to the outer surface of the developer carrier and the outer surface of the developer carrier (hereinafter referred to as a regulation gap). This promotes the conveyance of the developer. As a result, even if, for example, the deterioration of the developer progresses with time and the additive contained in the developer adheres to the magnetic carrier, the flowability of the developer drops and some transport resistance occurs to the developer. The deteriorated developer can be allowed to pass through the regulation gap by following the rotation of the developer carrier. Accordingly, it is possible to suppress a decrease in the amount of developer transported to the development area over time.

(態様B)
(態様A)において、前記現像剤担持体による現像剤搬送方向に対し直交する方向から見たとき、前記現像剤担持体の外表面に最も近い前記非磁性部材の規制端701a等の部分が前記磁性部材の先端部702aよりも前記現像剤担持体による現像剤搬送方向上流側に位置するよう、前記現像剤担持体の外表面に最も近い前記非磁性部材の部分を有する先端部701cが前記磁性部材の先端部よりも前記現像剤担持体による現像剤搬送方向上流側に延伸している。
本態様によれば、非磁性部材の先端部を磁性部材の先端部よりも現像剤担持体による現像剤搬送方向上流側に延伸することで、現像剤担持体の外表面に最も近い非磁性部材の部分が磁性部材の先端部よりも現像剤担持体による現像剤搬送方向上流側に位置するようにした現像剤規制部材を簡易に構成できる。
(Aspect B)
In (Aspect A), when viewed from a direction orthogonal to the developer transport direction by the developer carrier, the portion such as the regulation end 701a of the nonmagnetic member closest to the outer surface of the developer carrier is the A tip portion 701c having a portion of the nonmagnetic member closest to the outer surface of the developer carrying member is positioned on the upstream side in the developer transport direction by the developer carrying member relative to the tip portion 702a of the magnetic member. It extends to the upstream side in the developer transport direction by the developer carrier from the tip of the member.
According to this aspect, the nonmagnetic member closest to the outer surface of the developer carrier is formed by extending the tip of the nonmagnetic member to the upstream side in the developer transport direction by the developer carrier relative to the tip of the magnetic member. The developer regulating member can be easily configured such that this portion is positioned on the upstream side in the developer transport direction by the developer carrier relative to the tip of the magnetic member.

(態様C)
(態様B)において、前記現像剤担持体の外表面に最も近い前記非磁性部材の部分が前記磁性部材の先端部よりも前記現像剤搬送方向上流側に延伸する延伸量を、前記現像剤搬送方向に対し直交する方向で、異ならせる。
通常、磁界発生手段の磁極による磁界によって生じている磁気力は、経時により低下する。その磁気力の低下量が、現像剤担持体による現像剤搬送方向に対し直交する方向(以下、軸線方向という。)で異なる場合がある。現像剤担持体の外表面に最も近い非磁性部材の部分(以下、非磁性部材の先端部という。)の延伸量を、軸線方向で一定にしていると、軸線方向における非磁性部材の先端部の位置によっては、接線方向磁気力の現像剤に対し作用する向きが現像剤搬送方向上流側又は現像剤搬送方向下流側に向いていたり、あるいは接線方向磁気力の強さが異なったりする。この結果、上記規制ギャップにおける現像剤担持体上の現像剤の追従性が、軸線方向で異なってしまう。よって、上記規制ギャップを通過する現像剤の通過量は軸線方向で不均一になる。
本態様では、非磁性部材の先端部が磁性部材の先端部よりも現像剤搬送方向上流側に延伸する延伸量を軸線方向で異ならせる。その結果、現像剤規制部材の上記規制ギャップの入口における現像剤担持体の外表面での接線方向磁気力の向きを現像剤搬送方向下流側へ、軸線方向で一様に向かわせたり、接線方向磁気力の強さを軸線方向で略均一にしたりすることができる。これにより、上記規制ギャップを通過する現像剤の通過量は、軸線方向で、安定かつほぼ均一になり、画像濃度ムラを抑制することができる。
(Aspect C)
In (Aspect B), the amount of stretching that the portion of the non-magnetic member closest to the outer surface of the developer carrying member extends to the upstream side in the developer transport direction from the tip of the magnetic member is set to the developer transport. Different in the direction orthogonal to the direction.
Usually, the magnetic force generated by the magnetic field generated by the magnetic poles of the magnetic field generating means decreases with time. The amount of decrease in the magnetic force may differ in a direction (hereinafter referred to as an axial direction) orthogonal to the developer transport direction by the developer carrier. If the amount of stretching of the portion of the nonmagnetic member closest to the outer surface of the developer carrying member (hereinafter referred to as the tip portion of the nonmagnetic member) is constant in the axial direction, the tip portion of the nonmagnetic member in the axial direction Depending on the position, the direction in which the tangential magnetic force acts on the developer is directed upstream in the developer transport direction or downstream in the developer transport direction, or the strength of the tangential magnetic force is different. As a result, the followability of the developer on the developer carrying member in the regulation gap differs in the axial direction. Therefore, the amount of developer passing through the regulation gap is not uniform in the axial direction.
In this aspect, the amount of extension at which the tip of the nonmagnetic member extends to the upstream side in the developer transport direction from the tip of the magnetic member is varied in the axial direction. As a result, the direction of the tangential magnetic force on the outer surface of the developer carrier at the entrance of the regulation gap of the developer regulating member is uniformly directed in the axial direction toward the downstream side in the developer conveying direction, or the tangential direction. The strength of the magnetic force can be made substantially uniform in the axial direction. As a result, the amount of developer passing through the regulation gap is stable and substantially uniform in the axial direction, and image density unevenness can be suppressed.

(態様D)
(態様C)において、前記非磁性部材の前記現像剤搬送方向に対し直交する方向における中央部701dが、現像時に前記現像剤担持体による現像剤搬送方向下流側へ撓んだときに、前記非磁性部材の前記現像剤搬送方向に対し直交する方向における両端部701eとほぼ同じ位置になるよう、前記非磁性部材の中央部の前記延伸量を異ならせる。
現像剤規制部材は、通常、現像剤搬送方向に対し直交する方向における両端部で現像装置のケーシング等に固定されている。現像時、現像剤が現像剤担持体の表面移動によって現像剤規制部材へ移動し、その現像剤は現像剤規制部材の現像剤搬送方向上流側の側面によって堰き止められ、その側面には現像剤による圧力が加わる。この結果、現像剤規制部材の現像剤搬送方向に対し直交する方向おける中央部は現像剤担持体による現像剤搬送方向下流側へ撓み、現像剤規制部材の両端部は中央部に比べて大きくは撓まない。そのとき、現像剤規制部材の規制磁極に対する位置について現像剤規制部材の中央部と両端部とでは互いに異なり、上記規制ギャップを通過する現像剤の通過量について現像剤規制部材の中央部と両端部との間に差が生じる。よって、上記規制ギャップを通過する現像剤について現像剤担持体の現像剤搬送方向に対し直交する方向で不均一になる。
本態様では、現像剤規制部材が現像時に現像剤搬送方向下流側へ撓んだときに、非磁性部材の中央部と両端部とほぼ同じ位置になる。その結果、現像剤規制部材の規制磁極に対する位置について、現像剤規制部材の中央部と両端部とで互いに略同じとなる。これにより、現像剤規制部材の上記規制ギャップの入口における現像剤担持体の外表面での接線方向磁気力の向きや強さが、現像剤担持体の中央部と両端部とで互いに略同じになる。その規制ギャップを通過する現像剤の通過量は、現像剤規制部材の中央部と両端部との差もほぼなくなる。したがって、現像剤規制部材の上記規制ギャップを通過する現像剤は、現像剤担持体の現像剤搬送方向でほぼ均一になり、現像剤規制部材の撓みによる画像濃度ムラを抑制することができる。
(Aspect D)
In (Aspect C), when the central portion 701d of the nonmagnetic member in the direction orthogonal to the developer transport direction is bent downstream in the developer transport direction by the developer carrier during development, the non-magnetic member The stretching amount of the central portion of the non-magnetic member is made different so that the both ends 701e in the direction orthogonal to the developer transport direction of the magnetic member are substantially the same position.
The developer regulating member is usually fixed to the casing of the developing device at both ends in a direction orthogonal to the developer transport direction. At the time of development, the developer moves to the developer regulating member by the surface movement of the developer carrying member, and the developer is blocked by the side surface of the developer regulating member on the upstream side in the developer conveying direction. Pressure from is applied. As a result, the central portion of the developer regulating member in the direction orthogonal to the developer conveying direction is bent downstream in the developer conveying direction by the developer carrying member, and both end portions of the developer regulating member are largely compared to the central portion. Does not flex. At this time, the central portion and both end portions of the developer regulating member are different from each other in the center portion and both end portions of the developer regulating member with respect to the position of the developer regulating member with respect to the regulating magnetic pole. A difference occurs between Therefore, the developer passing through the regulation gap becomes non-uniform in the direction orthogonal to the developer transport direction of the developer carrier.
In this aspect, when the developer regulating member bends to the downstream side in the developer transport direction during development, the center portion and both end portions of the non-magnetic member are substantially at the same position. As a result, the position of the developer restricting member relative to the restricting magnetic pole is substantially the same at the center and both ends of the developer restricting member. As a result, the direction and strength of the tangential magnetic force on the outer surface of the developer carrier at the entrance of the regulation gap of the developer regulation member are substantially the same at the center and both ends of the developer carrier. Become. The amount of the developer passing through the regulation gap is almost the same as the difference between the central portion and both ends of the developer regulating member. Therefore, the developer passing through the regulation gap of the developer regulating member becomes substantially uniform in the developer carrying direction of the developer carrying member, and image density unevenness due to the deflection of the developer regulating member can be suppressed.

(態様E)
像担持体と、該像担持体の表面を帯電する帯電手段と、該像担持体の帯電された表面を露光して潜像を形成する露光手段と、該像担持体上の潜像を現像する現像手段と、該像担持体の表面をクリーニングするクリーニング手段とを有する画像形成装置の本体に対して着脱可能であり、少なくとも該像担持体と該現像手段とが一体的に支持されたプロセスカートリッジにおいて、該現像手段が、(態様A)〜(態様D)のいずれかの現像装置である。
本態様では、現像剤規制部材と現像剤担持体との隙間を通過する現像剤は狙いの量となり、経時による現像領域への現像剤搬送量の低下を抑制することができる。これにより、画像濃度低下を抑制できる現像装置の画像形成装置本体に対する交換性を高めることができる。
(Aspect E)
An image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged surface of the image carrier to form a latent image, and developing a latent image on the image carrier A process in which at least the image carrier and the developing unit are integrally supported, the developing unit being detachable from the main body of the image forming apparatus having a developing unit and a cleaning unit for cleaning the surface of the image carrier. In the cartridge, the developing means is the developing device according to any one of (Aspect A) to (Aspect D).
In this aspect, the developer passing through the gap between the developer regulating member and the developer carrying member becomes a target amount, and a decrease in the developer transport amount to the development region over time can be suppressed. Thereby, the exchangeability with respect to the image forming apparatus main body of the developing device which can suppress a reduction in image density can be improved.

(態様F)
像担持体と、該像担持体の表面を帯電する帯電手段と、該像担持体の帯電された表面を露光して潜像を形成する露光手段と、該像担持体上の潜像を現像する現像手段と、該像担持体の表面をクリーニングするクリーニング手段とを有する画像形成装置において、該現像手段が、(態様A)〜(態様D)のいずれかの現像装置である。
本態様によれば、現像剤規制部材と現像剤担持体との隙間を通過する現像剤は狙いの量となり、経時による現像領域への現像剤搬送量の低下を抑制することができる。よって、画像濃度低下を抑制できる。
(Aspect F)
An image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged surface of the image carrier to form a latent image, and developing a latent image on the image carrier In the image forming apparatus having a developing unit that performs cleaning and a cleaning unit that cleans the surface of the image carrier, the developing unit is any one of (Aspect A) to (Aspect D).
According to this aspect, the developer passing through the gap between the developer regulating member and the developer carrying member becomes a target amount, and it is possible to suppress a decrease in the developer transport amount to the development region over time. Therefore, a decrease in image density can be suppressed.

1 感光体
1Y イエロー用感光体
1M マゼンタ用感光体
1C シアン用感光体
1K 黒用感光体
2 排出搬送路
2a 排出搬送スクリュ
3 現像剤貯留部
4 現像装置
4Y イエロー用現像装置
4M マゼンタ用現像装置
4C シアン用現像装置
4K 黒用現像装置
4a 中央ケーシング
5 現像ローラ
5a 現像スリーブ
5b マグネットローラ
5c 中心
5d 地点
5e 地点
6 回収スクリュ
7 回収搬送路
8 供給スクリュ
9 供給搬送路
10 攪拌搬送路
11 攪拌スクリュ
12 ドクタブレード
14 転写張架ローラ
15 転写駆動ローラ
16 二次転写バックアップローラ
17 中間転写ユニット
18 プロセスカートリッジ
20 画像形成ユニット
21 光書込ユニット
22 二次転写装置
23 搬送張架ローラ
24 紙搬送ベルト
25 定着装置
26 定着ベルト
27 加圧ローラ
30 原稿台
32 コンタクトガラス
33 第一走行体
34 第二走行体
35 結像レンズ
36 読取センサ
42 給紙ローラ
43 ペーパーバンク
44 給紙カセット
45 分離ローラ
46 給紙路
47 搬送ローラ対
49 レジストローラ対
50 手差し給紙ローラ
51 手差しトレイ
52 手差し分離ローラ
53 手差し給紙路
57 スタック部
62 一次転写バイアスローラ
71 帯電ユニット
71a 帯電ローラ
71b 帯電ローラクリーナ
72 ドラムクリーニングユニット
72a クリーニングブレード
72b 排出スクリュ
72c 除電部材
72Y イエロー用ドラムクリーニングユニット
72M マゼンタ用ドラムクリーニングユニット
72C シアン用ドラムクリーニングユニット
90 ベルトクリーニング装置
94 現像剤排出口
100 プリンタ部
110 中間転写ベルト
120 放熱部
133 第一仕切り壁
134 第二仕切り壁
135 仕切り壁
150 現像電源
200 給紙装置
300 スキャナ
400 原稿自動搬送装置
440a 現像ケーシング
440b 回収壁
440c 現像領域
500 複写機
600 現像剤規制部材
601 現像剤規制部材本体
601a 規制端
601b 仮想線
602 磁性部材
602a 先端部
700 現像剤規制部材
701 現像剤規制部材本体
701a 規制端
701b 仮想線
701c 先端部
701d 中央部
701e 両端部
702 磁性部材
702a 先端部
DESCRIPTION OF SYMBOLS 1 Photoconductor 1Y Yellow photoconductor 1M Magenta photoconductor 1C Cyan photoconductor 1K Black photoconductor 2 Discharge conveyance path 2a Discharge conveyance path 3 Developer storage part 4 Developing device 4Y Yellow developing device 4M Magenta developing device 4C Cyan developing device 4K Black developing device 4a Central casing 5 Developing roller 5a Developing sleeve 5b Magnet roller 5c Center 5d Point 5e Point 6 Collection screw 7 Collection conveyance path 8 Supply screw 9 Supply conveyance path 10 Agitation conveyance path 11 Agitation screw 12 Doctor Blade 14 Transfer stretch roller 15 Transfer drive roller 16 Secondary transfer backup roller 17 Intermediate transfer unit 18 Process cartridge 20 Image forming unit 21 Optical writing unit 22 Secondary transfer device 23 Transport stretch roller 24 Paper transport belt 25 Fixing device 26 Fixing belt 27 Pressure roller 30 Document table 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 42 Paper feed roller 43 Paper bank 44 Paper feed cassette 45 Separating roller 46 Paper feed path 47 Conveyance Roller pair 49 Registration roller pair 50 Manual feed roller 51 Manual feed tray 52 Manual feed roller 53 Manual feed path 57 Stack unit 62 Primary transfer bias roller 71 Charging unit 71a Charging roller 71b Charging roller cleaner 72 Drum cleaning unit 72a Cleaning blade 72b Discharge Screw 72c Static eliminating member 72Y Yellow drum cleaning unit 72M Magenta drum cleaning unit 72C Cyan drum cleaning unit 90 Belt cleaning Place 94 Developer discharge port 100 Printer unit 110 Intermediate transfer belt 120 Heat radiating unit 133 First partition wall 134 Second partition wall 135 Partition wall 150 Developing power source 200 Paper feeder 300 Scanner 400 Automatic document feeder 440a Developing casing 440b Collection wall 440c Development area 500 Copier 600 Developer restriction member 601 Developer restriction member main body 601a Restriction end 601b Virtual line 602 Magnetic member 602a Tip end 700 Developer restriction member 701 Developer restriction member main body 701a Restriction end 701b Virtual line 701c Tip end 701d Center 701e Both ends 702 Magnetic member 702a Tip

特開2007−188111号公報JP 2007-188111 A

Claims (6)

磁界発生手段を中空体内に配置して移動し、該磁界発生手段の磁力により該中空体の外表面上に磁性キャリアとトナーとからなる二成分の現像剤を担持して自身が回転することでその現像剤を搬送する現像剤担持体と、非磁性部材と磁性部材とからなり、かつ、該現像剤担持体上の現像剤の量を規制する現像剤規制部材とを備え、前記磁性部材は前記非磁性部材に対し前記現像剤担持体による現像剤搬送方向上流側に設置させている現像装置において、
前記現像剤担持体の外表面での前記磁界発生手段による磁界によって前記現像剤担持体上の現像剤に対し働く接線方向成分の磁気力が前記現像剤担持体上の前記現像剤に対し作用する向きが前記現像剤担持体による現像剤搬送方向下流側に向いている前記現像剤担持体の外表面の部分に、前記現像剤担持体の外表面に最も近い前記非磁性部材の部分が対向していることを特徴とする現像装置。
The magnetic field generating means is disposed and moved in the hollow body, and the magnetic force of the magnetic field generating means carries a two-component developer composed of a magnetic carrier and toner on the outer surface of the hollow body and rotates itself. A developer carrying member that conveys the developer, a developer regulating member that includes a non-magnetic member and a magnetic member and regulates the amount of the developer on the developer carrying member, and the magnetic member includes: In the developing device installed on the upstream side in the developer transport direction by the developer carrier relative to the non-magnetic member,
Magnetic force of a tangential component acting on the developer on the developer carrying member acts on the developer on the developer carrying member by a magnetic field generated by the magnetic field generating means on the outer surface of the developer carrying member. The portion of the non-magnetic member closest to the outer surface of the developer carrying member faces the portion of the outer surface of the developer carrying member whose direction faces the downstream side in the developer transport direction by the developer carrying member. A developing device.
請求項1記載の現像装置において、
前記現像剤担持体による現像剤搬送方向に対し直交する方向から見たとき、前記現像剤担持体の外表面に最も近い前記非磁性部材の部分が前記磁性部材の先端部よりも前記現像剤担持体による現像剤搬送方向上流側に位置するよう、前記現像剤担持体の外表面に最も近い前記非磁性部材の部分を有する先端部が前記磁性部材の先端部よりも前記現像剤担持体による現像剤搬送方向上流側に延伸していることを特徴とする現像装置。
The developing device according to claim 1,
When viewed from the direction orthogonal to the developer transport direction by the developer carrier, the portion of the nonmagnetic member closest to the outer surface of the developer carrier is more than the tip of the magnetic member. The tip having the portion of the non-magnetic member closest to the outer surface of the developer carrying member is located on the upstream side in the developer conveying direction by the body, and the developer carrying member develops more than the tip of the magnetic member. A developing device characterized in that the developing device extends upstream in the agent transport direction.
請求項2記載の現像装置において、
前記現像剤担持体の外表面に最も近い前記非磁性部材の部分が前記磁性部材の先端部よりも前記現像剤搬送方向上流側に延伸する延伸量を、前記現像剤搬送方向に対し直交する方向で、異ならせることを特徴とする現像装置。
The developing device according to claim 2, wherein
A direction perpendicular to the developer transport direction is an extension amount of the portion of the non-magnetic member closest to the outer surface of the developer carrying member that extends to the upstream side of the developer transport direction from the tip of the magnetic member. A developing device characterized in that it is different.
請求項3記載の現像装置において、
前記非磁性部材の前記現像剤搬送方向に対し直交する方向における中央部が、現像時に前記現像剤担持体による現像剤搬送方向下流側へ撓んだときに、前記非磁性部材の前記現像剤搬送方向に対し直交する方向における両端部とほぼ同じ位置になるよう、前記非磁性部材の中央部の前記延伸量を異ならせることを特徴とする現像装置。
The developing device according to claim 3.
When the central portion of the nonmagnetic member in the direction orthogonal to the developer transport direction is bent downstream in the developer transport direction by the developer carrier during development, the developer transport of the nonmagnetic member is performed. The developing device characterized in that the stretching amount of the central portion of the nonmagnetic member is varied so as to be substantially the same position as both end portions in a direction orthogonal to the direction.
像担持体と、該像担持体の表面を帯電する帯電手段と、該像担持体の帯電された表面を露光して潜像を形成する露光手段と、該像担持体上の潜像を現像する現像手段と、該像担持体の表面をクリーニングするクリーニング手段とを有する画像形成装置の本体に対して着脱可能であり、少なくとも該像担持体と該現像手段とが一体的に支持されたプロセスカートリッジにおいて、
該現像手段が、請求項1〜4のいずれかの現像装置であることを特徴とするプロセスカートリッジ。
An image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged surface of the image carrier to form a latent image, and developing a latent image on the image carrier A process in which at least the image carrier and the developing unit are integrally supported, the developing unit being detachable from the main body of the image forming apparatus having a developing unit and a cleaning unit for cleaning the surface of the image carrier. In the cartridge,
5. A process cartridge, wherein the developing means is the developing device according to claim 1.
像担持体と、該像担持体の表面を帯電する帯電手段と、該像担持体の帯電された表面を露光して潜像を形成する露光手段と、該像担持体上の潜像を現像する現像手段と、該像担持体の表面をクリーニングするクリーニング手段とを有する画像形成装置において、
該現像手段が、請求項1〜4のいずれかの現像装置であることを特徴とする画像形成装置。
An image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged surface of the image carrier to form a latent image, and developing a latent image on the image carrier In an image forming apparatus having a developing means for cleaning and a cleaning means for cleaning the surface of the image carrier,
An image forming apparatus, wherein the developing means is the developing apparatus according to claim 1.
JP2015172004A 2015-06-11 2015-09-01 Developing device, process cartridge, and image forming apparatus Pending JP2017003957A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63225270A (en) * 1987-03-16 1988-09-20 Canon Inc Developing device
JPH11161007A (en) * 1997-11-27 1999-06-18 Toshiba Corp Developing device
JPH11327305A (en) * 1998-05-15 1999-11-26 Canon Inc Developing device and image forming device
US20110142500A1 (en) * 2009-12-10 2011-06-16 Kabushiki Kaisha Toshiba Developing device, developing method and image forming apparatus
JP2014178356A (en) * 2013-03-13 2014-09-25 Ricoh Co Ltd Developing device, process cartridge, and image forming apparatus

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63225270A (en) * 1987-03-16 1988-09-20 Canon Inc Developing device
JPH11161007A (en) * 1997-11-27 1999-06-18 Toshiba Corp Developing device
JPH11327305A (en) * 1998-05-15 1999-11-26 Canon Inc Developing device and image forming device
US20110142500A1 (en) * 2009-12-10 2011-06-16 Kabushiki Kaisha Toshiba Developing device, developing method and image forming apparatus
JP2014178356A (en) * 2013-03-13 2014-09-25 Ricoh Co Ltd Developing device, process cartridge, and image forming apparatus

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