JP6862918B2

JP6862918B2 - Develop equipment and image forming equipment

Info

Publication number: JP6862918B2
Application number: JP2017038301A
Authority: JP
Inventors: 慶太斉藤; 順哉平山
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 2017-03-01
Filing date: 2017-03-01
Publication date: 2021-04-21
Anticipated expiration: 2037-03-01
Also published as: JP2018146622A

Description

本発明は、現像装置および画像形成装置に関し、トナーと磁性キャリアとを有する２成分現像剤を用いた現像装置における、現像剤攪拌効率の改善に関する。本発明の現像装置および画像形成装置は、電子写真方式により画像を形成する現像装置および画像形成装置に関する。画像形成装置は、カラー、モノクロを問わず、デジタル複写機、ＦＡＸ、プリンタなどの電子写真装置、記録機器、表示装置などを含む。 The present invention relates to a developing apparatus and an image forming apparatus, and relates to an improvement in developer stirring efficiency in a developing apparatus using a two-component developer having toner and a magnetic carrier. The developing apparatus and image forming apparatus of the present invention relate to a developing apparatus and an image forming apparatus that form an image by an electrophotographic method. The image forming apparatus includes an electrophotographic apparatus such as a digital copier, a fax machine, and a printer, a recording apparatus, a display apparatus, and the like regardless of color or monochrome.

トナーが現像装置から消費され、現像剤中において一定のトナー濃度を下回ると、トナー補給口から現像装置内へトナーが補給される。補給されたトナーと現像装置中の現像剤の攪拌が不十分であると、トナー帯電量は不安定となり、低帯電トナーが発生する。低帯電トナーはトナー飛散やこぼれの原因となる。特に、高い画像カバレッジの画像を出力するとき、現像装置へのトナー補給速度は上がり、現像剤とトナーの攪拌が不十分となる場合がある。 When the toner is consumed from the developing device and falls below a certain toner concentration in the developing agent, the toner is replenished from the toner replenishment port into the developing device. If the replenished toner and the developer in the developing device are not sufficiently agitated, the toner charge amount becomes unstable and low-charged toner is generated. Low-charged toner causes toner scattering and spillage. In particular, when an image with high image coverage is output, the toner replenishment speed to the developing device may increase, and the stirring between the developer and the toner may be insufficient.

特開２００７−６５４００号公報（特許文献１）には、現像剤の攪拌効率を上げる方法として、現像装置の壁面と攪拌路中のスクリュー軸との間に磁界を発生させる技術が開示されている。トナー補給時に所定時間磁界を発生させ、現像剤が磁気チェーンを通過することにより、攪拌効率を上げている。 Japanese Unexamined Patent Publication No. 2007-65400 (Patent Document 1) discloses a technique for generating a magnetic field between the wall surface of a developing apparatus and a screw shaft in a stirring path as a method for increasing the stirring efficiency of a developing agent. .. A magnetic field is generated for a predetermined time when the toner is replenished, and the developer passes through the magnetic chain to improve the stirring efficiency.

特開２００７−６５４００号公報JP-A-2007-65400

特許文献１では、現像装置の下面外に、電磁石が設けられている。電磁石のオン制御、オフ制御により、攪拌軸に設けられた磁性体と電磁石との間の磁場の形成のオン制御、オフ制御を行なう。通常時は攪拌搬送羽根が電磁石に近接したときに電磁石をオフし、遠ざかったときに電磁石をオンする。トナー補給時には、所定時間磁界を発生させ、現像剤が磁気チェーンを通過することにより、攪拌効率を向上させる。このように、特許文献１では、トナーの補給のタイミングに合わせた磁界のオン制御、オフ制御を行なっている。 In Patent Document 1, an electromagnet is provided outside the lower surface of the developing apparatus. By on-control and off-control of the electromagnet, on-control and off-control of the formation of a magnetic field between the magnetic material provided on the stirring shaft and the electromagnet are performed. Normally, the electromagnet is turned off when the stirring and conveying blades are close to the electromagnet, and the electromagnet is turned on when the stirring and conveying blades are moved away. When the toner is replenished, a magnetic field is generated for a predetermined time, and the developer passes through the magnetic chain to improve the stirring efficiency. As described above, in Patent Document 1, on control and off control of the magnetic field are performed according to the timing of toner replenishment.

しかし、磁界の強度や磁界の印加時間制御に関する記載はない。そのため、トナー補給速度の高低に関わらず、一定強度の磁界を印加することになり、現像剤に対して補給されるトナーに攪拌の過不足が生じる。 However, there is no description about the strength of the magnetic field and the control of the application time of the magnetic field. Therefore, a magnetic field having a constant strength is applied regardless of the speed of toner replenishment, and the toner replenished with respect to the developer is excessively or insufficiently agitated.

トナー補給速度が高く、攪拌が不足すると、帯電量が不安定となり、低帯電トナーが生じ易くなる。他方、トナー補給速度が低く、攪拌が過剰となると、現像剤の劣化が進み、トナー帯電量が低くなる。即ち、トナー補給速度に合わせて攪拌状態を調整しなければ、攪拌の過不足によって低帯電トナーが発生し、トナー飛散やこぼれが発生し易くなる。 If the toner replenishment speed is high and stirring is insufficient, the amount of charge becomes unstable and low-charged toner is likely to be generated. On the other hand, if the toner replenishment rate is low and the stirring is excessive, the developer deteriorates and the toner charge amount becomes low. That is, if the stirring state is not adjusted according to the toner replenishment speed, low-charged toner is generated due to excess or deficiency of stirring, and toner scattering or spillage is likely to occur.

本発明の目的は、上記課題に鑑みてなされたものであり、トナー補給速度に合わせた磁界制御を行うことで、補給されるトナーを現像剤に対して効率良く攪拌することが可能な構成を備える、現像装置および画像形成装置を提供することにある。 An object of the present invention has been made in view of the above problems, and a configuration capable of efficiently stirring the replenished toner with respect to the developer by controlling the magnetic field according to the toner replenishment speed is provided. It is an object of the present invention to provide a developing apparatus and an image forming apparatus.

この現像装置は、トナーと磁性キャリアとを有する２成分現像剤を用いる現像装置であって、現像剤槽を有する筐体と、上記現像剤槽内に設置された搬送部材と、上記筐体の外部に設置された少なくとも１以上の磁界発生部材と、上記磁界発生部材の駆動制御部と、を備え、上記駆動制御部は、上記現像剤槽へのトナー補給速度に応じて、磁界強度および磁界発生時間の少なくとも一方を制御する。 This developing device is a developing device that uses a two-component developer having a toner and a magnetic carrier, and includes a housing having a developing agent tank, a transport member installed in the developing agent tank, and the housing. At least one magnetic field generating member installed externally and a drive control unit for the magnetic field generating member are provided, and the drive control unit has a magnetic field strength and a magnetic field according to the toner supply speed to the developing agent tank. Control at least one of the occurrence times.

他の形態においては、上記磁界発生部材は、電磁石であり、上記駆動制御部は、上記トナー補給速度に応じて、振幅（電源電圧）の制御により上記磁界強度の制御、または、上記操作量（ｄｕｔｙ）の制御による上記磁界発生時間の制御を行なう。 In another embodiment, the magnetic field generating member is an electromagnet, and the drive control unit controls the magnetic field strength by controlling the amplitude (power supply voltage) according to the toner replenishment speed, or the operation amount ( The magnetic field generation time is controlled by controlling the duty).

他の形態においては、上記駆動制御部は、上記操作量（ｄｕｔｙ）の制御による上記磁界発生時間の制御を行なう。 In another embodiment, the drive control unit controls the magnetic field generation time by controlling the duty.

他の形態においては、上記搬送部材は、回転軸と、上記回転軸周りに設けられた螺旋羽根と、を含み、上記螺旋羽根は、磁性体を含む。 In another form, the transport member includes a rotating shaft and spiral blades provided around the rotating shaft, and the spiral blade contains a magnetic material.

他の形態においては、上記螺旋羽根の先端を含む領域に上記磁性体が設けられている。
他の形態においては、上記搬送部材は、回転軸と、上記回転軸周りに設けられた第１螺旋羽根および第２螺旋羽根と、を含む。 In other forms, the magnetic material is provided in a region including the tip of the spiral blade.
In another form, the transport member includes a rotating shaft and first and second spiral blades provided around the rotating shaft.

他の形態においては、上記第１螺旋羽根および上記第２螺旋羽根のいずれか一方の羽根厚さが、他方の羽根厚さよりも大きく設けられている。 In another form, the blade thickness of either the first spiral blade or the second spiral blade is provided to be larger than the thickness of the other blade.

他の形態においては、上記第１螺旋羽根および上記第２螺旋羽根のいずれか一方の羽根径が、他方の羽根径よりも大きく設けられている。 In another form, the blade diameter of either the first spiral blade or the second spiral blade is provided to be larger than the diameter of the other blade.

他の形態においては、上記第１螺旋羽根および上記第２螺旋羽根の少なくともいずれか一方は、その先端を含む領域に磁性体が設けられている。 In other forms, at least one of the first spiral blade and the second spiral blade is provided with a magnetic material in a region including the tip thereof.

他の形態においては、上記筐体と上記磁界発生部材の間に、上記搬送部材の延びる方向に沿って磁性部材が設けられている。 In another form, a magnetic member is provided between the housing and the magnetic field generating member along the extending direction of the transport member.

他の形態においては、上記現像剤槽は、上記搬送部材が延びる方向に沿って配置された仕切板によって仕切られている。 In another form, the developer tank is partitioned by partition plates arranged along the direction in which the transport member extends.

他の形態においては、上記仕切板は、磁性体である。
他の形態においては、上記仕切板は、上記磁界発生部材により磁化されている。 In other forms, the partition plate is a magnetic material.
In other forms, the partition plate is magnetized by the magnetic field generating member.

この画像形成装置は、像担持体と、上記像担持体に対向配置され、上記像担持体に形成された潜像を現像する現像装置と、を備え、上記現像装置は、上述のいずれかに記載の現像装置である。 The image forming apparatus includes an image carrier and a developing apparatus that is arranged facing the image carrier and develops a latent image formed on the image bearing, and the developing apparatus can be any of the above. The developing apparatus according to the above.

この現像装置および画像形成装置によれば、トナー補給速度に合わせた磁界制御を行うことで、補給されるトナーを現像剤に対して効率良く攪拌することが可能な構成を備える、現像装置および画像形成装置を提供することができる。 According to the developing apparatus and the image forming apparatus, the developing apparatus and the image are provided with a configuration capable of efficiently stirring the replenished toner with respect to the developer by controlling the magnetic field according to the toner replenishment speed. A forming device can be provided.

実施の形態の画像形成装置の構成を示す側面図である。It is a side view which shows the structure of the image forming apparatus of embodiment. 実施の形態の第２搬送部材の構成を示す図である。It is a figure which shows the structure of the 2nd transport member of embodiment. 実施例１の高い画像カバレッジの場合のトナー補給速度を示す図である。It is a figure which shows the toner replenishment rate in the case of the high image coverage of Example 1. FIG. 実施例１の低い画像カバレッジの場合のトナー補給速度を示す図である。It is a figure which shows the toner replenishment rate in the case of low image coverage of Example 1. FIG. 電源電圧（磁界強度）を変化させた場合の画像カバレッジと飛散量との関係を示す図である。It is a figure which shows the relationship between the image coverage and the scattering amount when the power supply voltage (magnetic field strength) is changed. 実施例２の第１搬送部材の螺旋羽根の先端部分に磁性体が設けられた状態を示す図である。It is a figure which shows the state which the magnetic material is provided in the tip part of the spiral blade of the 1st transport member of Example 2. 実施例２の第１搬送部材の先端に、磁性成分を含まない通常の樹脂を用いた場合と、磁性成分を含む付着物を用いた場合との飛散量の比較を示した図である。It is a figure which showed the comparison of the amount of scattering between the case where the ordinary resin which does not contain a magnetic component is used for the tip of the 1st transport member of Example 2 and the case where the deposit which contains a magnetic component is used. 実施例３の二条のスクリューを用いた第１搬送部材を示す図である。It is a figure which shows the 1st transport member using the screw of 2 articles of Example 3. 実施例３の二条のスクリューを用いた場合に、第１螺旋羽根の先端に磁性成分を含む付着物を用いた場合と、第２螺旋羽根の先端に磁性成分を含まない通常の樹脂を用いた場合との飛散量を比較を示した図である。When the two screws of Example 3 were used, a deposit containing a magnetic component was used at the tip of the first spiral blade, and a normal resin containing no magnetic component was used at the tip of the second spiral blade. It is the figure which showed the comparison of the amount of scattering with the case. 実施例４の羽根厚さの異なる螺旋羽根の二条スクリューを用いた第１搬送部材を示す図である。It is a figure which shows the 1st transport member using the double screw of the spiral blade of a different blade thickness of Example 4. 実施例４の羽根厚さの異なる螺旋羽根の二条スクリューを用いた第１搬送部材の場合と、一条スクリューを用いた第１搬送部材の場合との飛散量を比較を示した図である。FIG. 5 is a diagram showing a comparison of the amount of scattering between the case of the first transport member using a double-row screw of spiral blades having different blade thicknesses of the fourth embodiment and the case of the first transport member using a single-row screw. 実施例５の上記実施例３の先端に磁性体を用いた第１螺旋羽根を有する第１搬送部材において、第１螺旋羽根の羽根径を、第２螺旋羽根の羽根径よりも大きくした図である。In the first transport member having the first spiral blade using a magnetic material at the tip of the third embodiment of the fifth embodiment, the blade diameter of the first spiral blade is made larger than the blade diameter of the second spiral blade. is there. 実施例５のｌ上記実施例３の先端に磁性体を用いた第１螺旋羽根を有する第１搬送部材において、第１螺旋羽根の羽根径を、第２螺旋羽根の羽根径よりも大きくした場合と、第１螺旋羽根の羽根径と第２螺旋羽根の羽根径とが同じ場合との飛散量を比較した図である。Example 5 l When the blade diameter of the first spiral blade is larger than the blade diameter of the second spiral blade in the first transport member having the first spiral blade using a magnetic material at the tip of the third embodiment. It is a figure comparing the amount of scattering when the blade diameter of the 1st spiral blade and the blade diameter of the 2nd spiral blade are the same. 実施例６の上記実施例４の第２螺旋羽根の羽根厚さを第１螺旋羽根の羽根厚さよりも厚くした第１螺旋羽根を有する第１搬送部材において、第２螺旋羽根の羽根径を、第１螺旋羽根の羽根径よりも大きくした図である。In the first transport member having the first spiral blade in which the blade thickness of the second spiral blade of the fourth embodiment of the sixth embodiment is thicker than the blade thickness of the first spiral blade, the blade diameter of the second spiral blade is set. It is the figure which made it larger than the blade diameter of the 1st spiral blade. 実施例６の第２螺旋羽根の羽根径を第１螺旋羽根の羽根径よりも大きくした場合と、第１螺旋羽根の羽根径と第２螺旋羽根の羽根径とが同じ場合との飛散量を比較した図である。The amount of scattering is calculated when the blade diameter of the second spiral blade of Example 6 is larger than the blade diameter of the first spiral blade and when the blade diameter of the first spiral blade and the blade diameter of the second spiral blade are the same. It is a comparison figure. 実施例７の第１搬送部材の回転軸の延びる方向に沿って、Ｆｅ系の磁性材が配置され、少なくとも１か所に電磁石が配置されている状態を示す図である。It is a figure which shows the state which the Fe-based magnetic material is arranged along the extending direction of the rotation axis of the 1st transport member of Example 7, and the electromagnet is arranged in at least one place. 実施例８の仕切板を示す拡大図である。It is an enlarged view which shows the partition plate of Example 8.

本実施の形態における現像装置および画像形成装置について、以下、図を参照しながら説明する。以下に説明する実施の形態において、個数、量などに言及する場合、特に記載がある場合を除き、本発明の範囲は必ずしもその個数、量などに限定されない。同一の部品、相当部品に対しては、同一の参照番号を付し、重複する説明は繰り返さない場合がある。図面においては、実際の寸法の比率に従って図示しておらず、構造の理解を容易にするために、構造が明確となるように比率を変更して図示している箇所がある。 The developing device and the image forming device according to the present embodiment will be described below with reference to the drawings. When the number, quantity, etc. are referred to in the embodiments described below, the scope of the present invention is not necessarily limited to the number, quantity, etc., unless otherwise specified. The same parts and equivalent parts may be given the same reference number, and duplicate explanations may not be repeated. In the drawings, some parts are not shown according to the actual dimensional ratios, and some parts are shown by changing the ratios so that the structure becomes clear in order to facilitate understanding of the structure.

画像形成装置は、スキャナー機能、複写機能、プリンタとしての機能、ファクシミリ機能、データ通信機能、およびサーバ機能を備えたＭＦＰ、ファクシミリ装置、または複写機を含む。 The image forming apparatus includes an MFP, a facsimile apparatus, or a copying machine having a scanner function, a copying function, a function as a printer, a facsimile function, a data communication function, and a server function.

以下の説明において、「トナー補給速度」とは、（１）ある一定期間内（例えば１ジョブ間、トナー補給していない時間を含む）あたりのトナー補給量、または、（２）単位時間あたりのトナー補給量（トナー補給している時間のみ）を意味する。 In the following description, the "toner replenishment speed" means (1) the amount of toner replenished within a certain period (for example, for one job, including the time when the toner is not replenished), or (2) per unit time. It means the amount of toner replenished (only the time during which the toner is replenished).

［実施の形態１：画像形成装置１００の構成］
図１および図２を参照して、本実施の形態における画像形成装置１００について説明する。図１は、画像形成装置１００の構成を示す側面図、図２は、第２搬送部材の構成を示す図である。 [Embodiment 1: Configuration of Image Forming Device 100]
The image forming apparatus 100 according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view showing the configuration of the image forming apparatus 100, and FIG. 2 is a diagram showing the configuration of the second transport member.

図１を参照して、画像形成装置１００は、感光体である像担持体１、現像装置２、転写ローラー４、クリーニングブレード５、帯電ローラー３、および、露光装置６を含む。像担持体１の回転方向（図中矢印Ａ方向）に沿って、現像装置２、転写ローラー４、クリーニングブレード５、帯電ローラー３、および、露光装置６がこの順で対向配置されている。 With reference to FIG. 1, the image forming apparatus 100 includes an image carrier 1, a developing apparatus 2, a transfer roller 4, a cleaning blade 5, a charging roller 3, and an exposure apparatus 6, which are photoconductors. The developing device 2, the transfer roller 4, the cleaning blade 5, the charging roller 3, and the exposure device 6 are arranged to face each other in this order along the rotation direction of the image carrier 1 (direction of arrow A in the drawing).

像担持体１と転写ローラー４との間には用紙等の転写媒体Ｐが挟み込まれ、像担持体１と転写ローラー４とによって挟み込まれた位置（ニップ領域）で、像担持体１に現像された画像が、転写媒体Ｐに転写される。転写媒体Ｐは、像担持体１のＡ方向に伴ない、図中矢印Ｃ方向に搬送される。 A transfer medium P such as paper is sandwiched between the image carrier 1 and the transfer roller 4, and the image carrier 1 is developed at a position (nip region) sandwiched between the image carrier 1 and the transfer roller 4. The image is transferred to the transfer medium P. The transfer medium P is conveyed in the direction of arrow C in the figure along with the direction of A of the image carrier 1.

現像装置２は、像担持体１に形成された潜像を現像する。現像装置２は、筐体２０を含む。この筐体２０は、紙面に対して垂直方向に延びる箱体であり、内部には現像剤槽１７が設けられている。この現像剤槽１７には、像担持体１の潜像を顕像化する為に像担持体１と並行に対向配置される現像剤担持体１１と、現像剤担持体へ現像剤２３を搬送する搬送部材としての第１搬送部材１８および第２搬送部材１９とを有している。筐体２０の現像剤槽１７において、第１搬送部材１８が位置する領域を第１攪拌路２０ａ、第２搬送部材１９が位置する領域を第２攪拌路２０ｂと称する。 The developing device 2 develops a latent image formed on the image carrier 1. The developing device 2 includes a housing 20. The housing 20 is a box body extending in the direction perpendicular to the paper surface, and a developer tank 17 is provided inside. In the developer tank 17, the developer carrier 11 is arranged in parallel with the image carrier 1 in order to visualize the latent image of the image carrier 1, and the developer 23 is conveyed to the developer carrier. It has a first transport member 18 and a second transport member 19 as transport members to be processed. In the developer tank 17 of the housing 20, the region where the first transport member 18 is located is referred to as a first stirring path 20a, and the region where the second transport member 19 is located is referred to as a second stirring path 20b.

図２に示すように、第１搬送部材１８は、回転軸１８ａと回転軸１８ａの周りに設けられた第１螺旋羽根１８ｂとをするスクリュー形態を有している。第２搬送部材１９も第１搬送部材１８と同様のスクリュー形態を有している。 As shown in FIG. 2, the first transport member 18 has a screw form having a rotating shaft 18a and a first spiral blade 18b provided around the rotating shaft 18a. The second transport member 19 also has the same screw form as the first transport member 18.

第１搬送部材１８および第２搬送部材１９は、現像剤担持体１１に平行に配置され、多くの現像装置では複数の搬送部材で構成されている。一般的には現像剤担持体１１に対向する位置に１つあるが、本実施の形態では、搬送部材に平行且つ壁を隔てて現像剤担持体１１とは反対方向にもう一つの計２本で構成されている。第１搬送部材１８および第２搬送部材１９は、互いに軸方向の端部で現像剤を受け渡しすることで、２本の搬送部材を現像剤が周回して搬送されている。 The first transport member 18 and the second transport member 19 are arranged in parallel with the developer carrier 11, and are composed of a plurality of transport members in many developing devices. Generally, there is one at a position facing the developer carrier 11, but in the present embodiment, a total of two other ones are parallel to the conveying member and separated by a wall in the direction opposite to the developer carrier 11. It is composed of. The first transport member 18 and the second transport member 19 transfer the developer at the ends in the axial direction to each other, so that the developer circulates around the two transport members and is transported.

再び、図１を参照して、筐体２０には、搬送部材で搬送中の現像剤２３へトナー２２を補給するトナー補給口１５が、第１搬送部材１８の上方に設けられている。トナー補給口１５は、通常、現像剤担持体１１から最も遠い位置に置かれる。 Again, referring to FIG. 1, the housing 20 is provided with a toner supply port 15 above the first transport member 18 for supplying the toner 22 to the developer 23 being transported by the transport member. The toner supply port 15 is usually placed at the position farthest from the developer carrier 11.

現像剤槽１７は、第１搬送部材１８が位置する第１攪拌路２０ａと第２搬送部材１９が位置する第２攪拌路２０ｂとは、搬送部材が延びる方向に沿って配置された仕切板１０によって上部が連通する状態で仕切られている。 In the developer tank 17, the first stirring path 20a in which the first conveying member 18 is located and the second stirring path 20b in which the second conveying member 19 is located are partitioned plates 10 arranged along the direction in which the conveying member extends. The upper part is partitioned by communicating with each other.

筐体２０の現像剤担持体１１が像担持体１に対向する領域には、現像剤担持体１１を露出させるための現像開口２４が設けられている。現像剤担持体１１は、磁石ローラー２５と磁石ローラー２５の表面に設けられたスリーブローラー２６とを含む。スリーブローラー２６と像担持体１との間には、現像領域８が形成される。 In the region where the developer carrier 11 of the housing 20 faces the image carrier 1, a development opening 24 for exposing the developer carrier 11 is provided. The developer carrier 11 includes a magnet roller 25 and a sleeve roller 26 provided on the surface of the magnet roller 25. A developing region 8 is formed between the sleeve roller 26 and the image carrier 1.

筐体２０の内部において、現像剤担持体１１と第２搬送部材１９とが対向する領域には、現像剤回収領域１３が設けられている。筐体２０から現像剤担持体１１の表面に向けて延びるように設けられた規制部材１６によって現像剤担持体１１の表面に担持される現像剤２３の量が規制される。規制部材１６によって、現像剤担持体１１の表面から取り除かれた現像剤２３は、現像剤回収領域１３に落下し、再び現像剤２３として用いられる。 Inside the housing 20, a developer recovery region 13 is provided in a region where the developer carrier 11 and the second transport member 19 face each other. The amount of the developer 23 supported on the surface of the developer carrier 11 is regulated by the regulating member 16 provided so as to extend from the housing 20 toward the surface of the developer carrier 11. The developer 23 removed from the surface of the developer carrier 11 by the regulating member 16 falls into the developer recovery region 13 and is used again as the developer 23.

筐体２０の第１搬送部材１８を挟んでトナー補給口１５とは反対側（底側）には、ＡＴＤＣ（Automatic Toner Density Control）センサー２１が配置されている。さらに、筐体２０の外側において、ＡＴＤＣセンサー２１と対向する位置には、磁界発生装置９Ａが配置されている。 The ATDC (Automatic Toner Density Control) sensor 21 is arranged on the side (bottom side) opposite to the toner supply port 15 with the first transport member 18 of the housing 20 interposed therebetween. Further, on the outside of the housing 20, a magnetic field generator 9A is arranged at a position facing the ATDC sensor 21.

図２を参照して、磁界発生装置９Ａは、第１搬送部材１８の第１螺旋羽根１８ｂと同一ピッチで配置された複数の電磁石９を有する。電磁石の磁界強度および磁界発生時間の制御については、後述する。 With reference to FIG. 2, the magnetic field generator 9A has a plurality of electromagnets 9 arranged at the same pitch as the first spiral blade 18b of the first transport member 18. The control of the magnetic field strength and the magnetic field generation time of the electromagnet will be described later.

現像剤槽１７内の現像剤２３は、第１搬送部材１８および第２搬送部材１９の回転により混合攪拌され、摩擦帯電すると同時に現像剤槽１７内で循環搬送され、現像剤担持体１１の表面のスリーブローラー２６へと供給される。 The developer 23 in the developer tank 17 is mixed and agitated by the rotation of the first transport member 18 and the second transport member 19, is triboelectrically charged, and at the same time is circulated and transported in the developer tank 17 to the surface of the developer carrier 11. It is supplied to the sleeve roller 26 of the above.

現像剤２３は、現像剤担持体１１の内部の磁石ローラー２５の磁力によってスリーブローラー２６の表面側に保持され、スリーブローラー２６と共に回転移動して、現像剤担持体１１に対向して設けられた規制部材１６で通過量を規制される。現像剤担持体１１には直流電圧のみ、もしくは直流電圧に交流電圧を重畳したバイアスが加えられ、現像領域８において、像担持体１にトナーが現像される。 The developer 23 is held on the surface side of the sleeve roller 26 by the magnetic force of the magnet roller 25 inside the developer carrier 11, rotates with the sleeve roller 26, and is provided so as to face the developer carrier 11. The passing amount is regulated by the regulating member 16. Only the DC voltage or a bias in which the AC voltage is superimposed on the DC voltage is applied to the developer carrier 11, and the toner is developed on the image carrier 1 in the developing region 8.

現像領域８を通過した現像剤２３は、スリーブローラー２６の回転とともに現像剤槽１７に向けて搬送され、磁石ローラー２５に現像剤回収領域１３に対応する位置に設けられた反発磁界（不図示）によって現像剤担持体１１上から剥離され、現像剤槽１７内へと回収される。 The developer 23 that has passed through the developing region 8 is conveyed toward the developing agent tank 17 as the sleeve roller 26 rotates, and a repulsive magnetic field (not shown) provided on the magnet roller 25 at a position corresponding to the developing agent recovery region 13. It is peeled off from the developer carrier 11 and collected in the developer tank 17.

トナー補給口１５に設けられた不図示の補給制御部は、ＡＴＤＣセンサー２１の出力値から現像剤２３中のトナー濃度が画像濃度確保のための最低トナー濃度以下になったことを検出すると、非図示のトナー補給手段によってホッパ内に貯蔵されたトナー２２がトナー補給口１５を介して現像剤槽１７内へ供給される。トナー補給速度［ｇ／ｓｅｃ］は、画像カバレッジ、ＡＴＤＣセンサーの出力値の時間勾配から算出される。 When the replenishment control unit (not shown) provided in the toner replenishment port 15 detects from the output value of the ATDC sensor 21 that the toner concentration in the developer 23 is equal to or lower than the minimum toner concentration for ensuring the image density, it is not displayed. The toner 22 stored in the hopper by the illustrated toner replenishment means is supplied into the developer tank 17 through the toner replenishment port 15. The toner replenishment speed [g / sec] is calculated from the image coverage and the time gradient of the output value of the ATDC sensor.

画像カバレッジとは、用紙等の転写媒体Ｐの画像形成領域に対する出力画像領域（形成画像領域）の割合を意味する。 The image coverage means the ratio of the output image area (formed image area) to the image forming area of the transfer medium P such as paper.

図２を参照して、磁界発生装置９Ａは、筐体２０の第１搬送部材１８の下方に設置される。磁界発生装置９Ａは、第１搬送部材１８の第１螺旋羽根１８ｂのピッチに対向するように複数配置されている。磁界発生装置９Ａの駆動は駆動制御部９１によって実行される。 With reference to FIG. 2, the magnetic field generator 9A is installed below the first transport member 18 of the housing 20. A plurality of magnetic field generators 9A are arranged so as to face the pitch of the first spiral blade 18b of the first transport member 18. The drive of the magnetic field generator 9A is executed by the drive control unit 91.

駆動制御部９１は、トナー２２の現像剤槽１７への補給速度に応じて、磁界強度および磁界発生時間の少なくとも一方を制御する。具体的には、駆動制御部９１は、電源９２と波形信号生成部９３とで構成され、波形信号生成部９３は、ＡＴＤＣセンサー２１から得られたトナー濃度情報（トナー補給速度［ｇ／ｓｅｃ］）９４と画像カバレッジ情報９５とを元に、電源９２から出力される信号波形に基づいて、磁界強度および磁界発生時間の少なくとも一方を制御する。 The drive control unit 91 controls at least one of the magnetic field strength and the magnetic field generation time according to the charging speed of the toner 22 to the developer tank 17. Specifically, the drive control unit 91 is composed of a power supply 92 and a waveform signal generation unit 93, and the waveform signal generation unit 93 contains toner concentration information (toner replenishment speed [g / sec]] obtained from the ATDC sensor 21. ) 94 and the image coverage information 95, at least one of the magnetic field strength and the magnetic field generation time is controlled based on the signal waveform output from the power supply 92.

各装置構成の一例を以下に示す。第１搬送部材１８の第１螺旋羽根１８ｂの最大径は２４ｍｍ。回転軸１８ａの軸径は１０ｍｍである。第１螺旋羽根１８ｂは、一条螺旋羽根であり、ピッチは３０ｍｍである。第１搬送部材１８の回転速度は、２００ｒｐｍである。第１搬送部材１８の回転方向は、図１で見た場合に反時計回転である。 An example of each device configuration is shown below. The maximum diameter of the first spiral blade 18b of the first transport member 18 is 24 mm. The shaft diameter of the rotating shaft 18a is 10 mm. The first spiral blade 18b is a single spiral blade and has a pitch of 30 mm. The rotation speed of the first transport member 18 is 200 rpm. The rotation direction of the first transport member 18 is counterclockwise when viewed in FIG.

第２搬送部材１９の螺旋羽根の最大径は２４ｍｍ、回転軸の軸径は１０ｍｍである。螺旋羽根は、一条螺旋羽根であり、ピッチは３０ｍｍである。第２搬送部材１９の回転速度は、２００ｒｐｍである。第２搬送部材１９の回転方向は、図１で見た場合に反時計回転である。 The maximum diameter of the spiral blade of the second transport member 19 is 24 mm, and the shaft diameter of the rotating shaft is 10 mm. The spiral blade is a single spiral blade and has a pitch of 30 mm. The rotation speed of the second transport member 19 is 200 rpm. The rotation direction of the second transport member 19 is counterclockwise when viewed in FIG.

現像剤担持体１１の直径は３０ｍｍ、スリーブローラー−２６の回転速度は６０ｒｐｍ、現像剤搬送量は２２０ｇ／ｍ^２、規制部材１６との隙間（ギャップ）は、０．６ｍｍである。 The diameter of the developer carrier 11 is 30 mm, the rotation speed of the sleeve roller-26 is 60 rpm, the developer transport amount is 220 g / m ² , and the gap with the regulating member 16 is 0.6 mm.

像担持体１へのバイアスは、トナーのベタ画像現像時は−５０Ｖ、非現像時は−５００Ｖである。現像剤担持体１１へのバイアスは、交流電圧（ＡＣ）は１０００Ｖｐｐ（１０ｋＨｚ）、直流電圧（ＤＣ）は−３５０Ｖである。現像剤２３には、コニカミノルタ株式会社製ｂｉｚｈｕｂＣ３６８用のＢｌａｃｋ現像剤を用いた。 The bias toward the image carrier 1 is −50 V when the toner is developed for a solid image, and −500 V when the toner is not developed. The bias to the developer carrier 11 is 1000 Vpp (10 kHz) for the AC voltage (AC) and −350 V for the DC voltage (DC). As the developer 23, a Black developer for bizhub C368 manufactured by Konica Minolta Co., Ltd. was used.

以下、上記構成を備える画像形成装置１００を用いた場合の具体的な各実施例について説明する。 Hereinafter, specific examples of using the image forming apparatus 100 having the above configuration will be described.

（実施例１）
図３から図５を参照して、実施例１の場合の電源電圧（磁界強度）変化時のトナーの飛散量について説明する。図３は、高い画像カバレッジの場合のトナー補給速度を示す図、図４は、低い画像カバレッジの場合のトナー補給速度を示す図、図５は、電源電圧（磁界強度）を変化させた場合の画像カバレッジと飛散量との関係を示す図である。 (Example 1)
With reference to FIGS. 3 to 5, the amount of toner scattered when the power supply voltage (magnetic field strength) changes in the first embodiment will be described. FIG. 3 is a diagram showing the toner replenishment speed in the case of high image coverage, FIG. 4 is a diagram showing the toner replenishment speed in the case of low image coverage, and FIG. 5 is a diagram when the power supply voltage (magnetic field strength) is changed. It is a figure which shows the relationship between the image coverage and the scattering amount.

実施例１においては、第２搬送部材１９を、磁性体を含有した樹脂を用いて形成し、第２搬送部材１９と筐体２０との間に磁界を発生させるように磁界発生装置９Ａを設け、駆動制御部９１から、トナー補給速度に応じて、振幅（電源電圧）の制御により前記磁界強度の制御を行なうトナー補給速度は、ＡＴＤＣセンサー２１と画像カバレッジ情報を元に算出する。 In the first embodiment, the second transport member 19 is formed by using a resin containing a magnetic material, and a magnetic field generator 9A is provided so as to generate a magnetic field between the second transport member 19 and the housing 20. The drive control unit 91 controls the magnetic field strength by controlling the amplitude (power supply voltage) according to the toner replenishment speed. The toner replenishment speed is calculated based on the ATDC sensor 21 and the image coverage information.

図３から図５を参照して、高い画像カバレッジ（図３）のときは、低い画像カバレッジ（図４）のときに対して、トナー補給速度［ｇ／ｓｅｃ］は画像カバレッジ比α分だけ高くなる。たとえば、高い画像カバレッジ３０％のときと低い画像カバレッジ５％のときの、電源電圧（磁界強度）変化時の飛散量の比較例を図７に示す。 With reference to FIGS. 3 to 5, when the image coverage is high (FIG. 3), the toner replenishment speed [g / sec] is higher by the image coverage ratio α than when the image coverage is low (FIG. 4). Become. For example, FIG. 7 shows a comparative example of the amount of scattering when the power supply voltage (magnetic field strength) changes when the high image coverage is 30% and when the low image coverage is 5%.

測定は、耐久実験装置でまず過酷な耐久試験として非現像（トナーを像担持体へ現像しない）モードで２時間駆動する。その後、画像カバレッジ５％、および、画像カバレッジ３０％での現像飛散量をパーティクルカウンター（リオン株式会社型式：ＫＲ−１１Ｂ：５μｍ以上で計測）で行なった。測定値は１分間の積算値である。電源電圧が大きいほど磁界強度は大きい。 The measurement is first driven by a durability experimental device for 2 hours in a non-developed (not developing the toner on the image carrier) mode as a harsh durability test. Then, the amount of development scattering at 5% image coverage and 30% image coverage was measured with a particle counter (Rion Co., Ltd. model: KR-11B: measured at 5 μm or more). The measured value is an integrated value for 1 minute. The larger the power supply voltage, the larger the magnetic field strength.

画像カバレッジ５％の１２Ｖでは、比較例１−１および実施例１−１において、飛散量に変化はない。しかし、画像カバレッジ３０％の２４Ｖ（実施例１−２）では、画像カバレッジ３０％の１２Ｖ（比較例１−２）よりも飛散量は減るが、画像カバレッジ３０％の３６Ｖ（実施例１−３）とすると攪拌が過剰となり飛散量は増える。但し、使用する現像剤の種類、量、攪拌速度、環境等によって適切な磁界強度は変化するため、本実施例の値は一意的には決まらない。 At 12V with an image coverage of 5%, there is no change in the amount of scattering in Comparative Example 1-1 and Example 1-1. However, at 24V with 30% image coverage (Example 1-2), the amount of scattering is smaller than that at 12V with 30% image coverage (Comparative Example 1-2), but 36V with 30% image coverage (Example 1-3). ), The stirring becomes excessive and the amount of scattering increases. However, since the appropriate magnetic field strength changes depending on the type, amount, stirring speed, environment, etc. of the developer used, the value of this embodiment is not uniquely determined.

駆動制御部９１は、振幅（電源電圧）に代わり、トナー補給速度に応じて、操作量（ｄｕｔｙ）の制御による磁界発生時間の制御を行なってもい。操作量（ｄｕｔｙ）を変化させ、正味の磁界強度を変化させた場合にも同様の効果が得られる。たとえば、操作量（ｄｕｔｙ）を３０から６０に変更すれば、磁界強度約２倍と同等の効果が得られる。 The drive control unit 91 may control the magnetic field generation time by controlling the operation amount (duty) according to the toner replenishment speed instead of the amplitude (power supply voltage). The same effect can be obtained when the operation amount (duty) is changed and the net magnetic field strength is changed. For example, if the operation amount (duty) is changed from 30 to 60, an effect equivalent to about twice the magnetic field strength can be obtained.

本実施例は磁界発生装置９Ａとして電磁石（近傍の磁界１０ｍＴから１００ｍＴ程度）を用いたが、磁界強度や印加時間を変更できる装置であればこれに限らない。 In this embodiment, an electromagnet (a magnetic field in the vicinity of 10 mT to about 100 mT) is used as the magnetic field generator 9A, but the device is not limited to this as long as the magnetic field strength and application time can be changed.

（実施例２）
図６および図７を参照して、実施例２について説明する。図６は、第１搬送部材１８の第１螺旋羽根１８ｂの先端部分に磁性体が設けられた状態を示す図、図７は、第１搬送部材の先端（数ｍｍ）に、磁性成分を含まない通常の樹脂を用いた場合（比較例）と、磁性成分を含む付着物を用いた場合（本実施例）との飛散量の比較を示した図である。 (Example 2)
The second embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a diagram showing a state in which a magnetic material is provided at the tip portion of the first spiral blade 18b of the first transport member 18, and FIG. 7 is a diagram showing a state in which a magnetic material is provided at the tip portion (several mm) of the first transport member 18. It is a figure which showed the comparison of the amount of scattering between the case of using the normal resin which does not exist (comparative example), and the case of using the deposit containing a magnetic component (this example).

図６に示すように、この実施例においては、第１搬送部材１８の第１螺旋羽根１８ｂの先端部分に、約１ｍｍ〜４ｍｍ幅の磁性体１８ｄを設けている。第１螺旋羽根１８ｂの先端部分に磁性体１８ｄを設けることにより、筐体２０と第１搬送部材１８の先端の間の磁束密度が高くなる。攪拌路中で最もせん断が大きくなる箇所（筐体２０と第１搬送部材１８の先端の間）において磁束密度を高めることによって、攪拌効果を高めることになる。 As shown in FIG. 6, in this embodiment, a magnetic body 18d having a width of about 1 mm to 4 mm is provided at the tip of the first spiral blade 18b of the first transport member 18. By providing the magnetic body 18d at the tip of the first spiral blade 18b, the magnetic flux density between the housing 20 and the tip of the first transport member 18 is increased. The stirring effect is enhanced by increasing the magnetic flux density at the portion of the stirring path where the shear is greatest (between the housing 20 and the tip of the first transport member 18).

図７に示すように、比較例２−１から比較例２−３に示すように、通常の樹脂を第１搬送部材１８の先端に設け、画像カバレッジおよび電源電圧を操作した場合に、画像カバレッジ３０％においては、電源電圧を２４Ｖにした場合に、飛散量を低下させている。この比較例２−３と本実施例の第１螺旋羽根１８ｂの先端部分に磁性体１８ｄを用いた実施例２−１を比較した場合、より飛散量を低下させることを可能にしている。 As shown in FIG. 7, as shown in Comparative Example 2-1 to Comparative Example 2-3, when a normal resin is provided at the tip of the first transport member 18 and the image coverage and the power supply voltage are manipulated, the image coverage is obtained. At 30%, the amount of scattering is reduced when the power supply voltage is set to 24V. When this Comparative Example 2-3 and Example 2-1 using the magnetic material 18d at the tip of the first spiral blade 18b of this example are compared, it is possible to further reduce the amount of scattering.

なお、本実施例では、第１螺旋羽根１８ｂの先端部分に磁性体を設けた場合について説明しているが、第１螺旋羽根１８ｂの全体が磁性体を含む構成であってもよい。 In this embodiment, the case where the magnetic material is provided at the tip of the first spiral blade 18b is described, but the entire first spiral blade 18b may include the magnetic material.

（実施例３）
図８および図９を参照して、実施例３について説明する。図８は、二条のスクリューを用いた第１搬送部材を示す図、図９は、二条のスクリューを用いた場合に、第１螺旋羽根の先端に磁性成分を含む付着物を用いた場合（本実施例）と、第２螺旋羽根の先端に磁性成分を含まない通常の樹脂を用いた場合（比較例）との飛散量を比較を示した図である。 (Example 3)
The third embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 is a diagram showing a first transport member using two screws, and FIG. 9 is a case where an deposit containing a magnetic component is used at the tip of the first spiral blade when the two screws are used (this). It is a figure which showed the comparison of the amount of scattering between the case (Example) and the case where the ordinary resin which does not contain a magnetic component is used for the tip of the 2nd spiral blade (comparative example).

この実施例の特徴は、第１搬送部材１８に、第１螺旋羽根１８ｂ１および第２螺旋羽根１８ｂ２を用いた、いわゆる二条のスクリューを用いている。さらに、第１螺旋羽根１８ｂ１および第２螺旋羽根１８ｂ２のいずれか一方は、その先端が実施例２と同様に、磁性体が用いられている。 The feature of this embodiment is that the first transport member 18 uses a so-called two-row screw using the first spiral blade 18b1 and the second spiral blade 18b2. Further, one of the first spiral blade 18b1 and the second spiral blade 18b2 uses a magnetic material at the tip thereof as in the second embodiment.

螺旋羽根の先端を磁性体とすると磁束密度の高まりにより、せん断が大きくなることが予測される。その分、搬送にロスが生じ、現像剤に意図しない劣化が発生してしまうことが懸念される場合がある。そこで、第１螺旋羽根１８ｂ１および第２螺旋羽根１８ｂ２のいずれか一方を、磁性体を含まない通常の樹脂とすることで、搬送効率と攪拌効率とを高めることができる。 If the tip of the spiral blade is made of a magnetic material, it is predicted that the shear will increase due to the increase in magnetic flux density. Therefore, there is a concern that a loss may occur in the transport and an unintended deterioration of the developer may occur. Therefore, by using either one of the first spiral blade 18b1 and the second spiral blade 18b2 as a normal resin containing no magnetic material, the transport efficiency and the stirring efficiency can be improved.

図９に示すように、第１螺旋羽根１８ｂ１の先端に磁性成分を含む付着物を用いた場合（実施例３−１）と、第２螺旋羽根１８ｂ２の先端に磁性成分を含まない通常の樹脂を用いた場合（比較例３−４）との比較した場合には、飛散量を低下させることを可能にしている。 As shown in FIG. 9, when an deposit containing a magnetic component is used at the tip of the first spiral blade 18b1 (Example 3-1), a normal resin containing no magnetic component at the tip of the second spiral blade 18b2. When compared with the case of using (Comparative Example 3-4), it is possible to reduce the amount of scattering.

（実施例４）
図１０および図１１を参照して、実施例４について説明する。図１０は、羽根厚さの異なる螺旋羽根の二条スクリューを用いた第１搬送部材を示す図、図１１は、羽根厚さの異なる螺旋羽根の二条スクリューを用いた第１搬送部材の場合（本実施例）と、一条スクリューを用いた第１搬送部材の場合（比較例）との飛散量を比較を示した図である。 (Example 4)
Example 4 will be described with reference to FIGS. 10 and 11. FIG. 10 is a diagram showing a first transport member using double-row screws of spiral blades having different blade thicknesses, and FIG. 11 is a case of a first transport member using double-row screws of spiral blades having different blade thicknesses (this). It is a figure which showed the comparison of the amount of scattering between the example (Example) and the case of the first transport member using a single thread screw (comparative example).

この実施例は、第１搬送部材１８が二条のスクリューであり、第１螺旋羽根１８ｂ１および第２螺旋羽根１８ｂ２のどちらか一方のスクリュー羽根厚さが厚いことにある。スクリュー羽根厚さが厚いと、その分スクリュー先端と筐体２０との間の押圧面積が増加し、せん断が大きくなる。他方、せん断が大きくなった分、羽根厚さが厚いスクリューは搬送機能が低下するため、残りのスクリューを通常の羽根厚さとし、搬送機能の低下による現像剤の劣化を防ぐ。 In this embodiment, the first transport member 18 is a double-threaded screw, and the screw blade thickness of either the first spiral blade 18b1 or the second spiral blade 18b2 is thick. When the screw blade thickness is thick, the pressing area between the screw tip and the housing 20 increases by that amount, and the shear increases. On the other hand, since the transfer function of a screw having a thick blade thickness deteriorates due to the increased shear, the remaining screw has a normal blade thickness to prevent deterioration of the developer due to a decrease in the transport function.

図１１に、第１螺旋羽根１８ｂの羽根厚さが通常の１．４ｍｍ程度の一条スクリューを用いた第１搬送部材（比較例４−１から４−３）と、一条目の第１螺旋羽根１８ｂ１に通常の羽根厚さ１．４ｍｍを用い、二条目の第２螺旋羽根１８ｂ２に羽根厚さ３．０ｍｍを用いた場合（実施例４-１）の飛散量の比較を示す。 FIG. 11 shows a first transport member (Comparative Examples 4-1 to 4-3) using a single-row screw having a blade thickness of about 1.4 mm for the first spiral blade 18b, and a first spiral blade of the first spiral blade. A comparison of the amount of scattering when a normal blade thickness of 1.4 mm is used for 18b1 and a blade thickness of 3.0 mm is used for the second spiral blade 18b2 of the second row (Example 4-1) is shown.

第１螺旋羽根１８ｂの羽根厚さが通常の１．４ｍｍ程度の一条スクリューを用いた第１搬送部材（比較例４−３）に比べ、一条目の第１螺旋羽根１８ｂ１に通常の羽根厚さ１．４ｍｍを用い、二条目の第２螺旋羽根１８ｂ２に羽根厚さ３．０ｍｍを用いた第１搬送部材（実施例４−１）場合には、飛散量を低下させることを可能にしている。 Compared to the first transport member (Comparative Example 4-3) using a single-row screw having a blade thickness of the first spiral blade 18b of about 1.4 mm, the blade thickness of the first spiral blade 18b1 of the first row has a normal blade thickness. In the case of the first transport member (Example 4-1) in which 1.4 mm is used and a blade thickness of 3.0 mm is used for the second spiral blade 18b2 of the second row, it is possible to reduce the amount of scattering. ..

（実施例５）
図１２および図１３を参照して、実施例５について説明する。図１２は、上記実施例３の先端に磁性体を用いた第１螺旋羽根を有する第１搬送部材において、第１螺旋羽根の羽根径を、第２螺旋羽根の羽根径よりも大きくした図、図１３は、上記実施例３の先端に磁性体を用いた第１螺旋羽根を有する第１搬送部材において、第１螺旋羽根の羽根径を、第２螺旋羽根の羽根径よりも大きくした場合（実施例）と、第１螺旋羽根の羽根径と第２螺旋羽根の羽根径とが同じ場合（比較例）との飛散量を比較した図である。 (Example 5)
The fifth embodiment will be described with reference to FIGS. 12 and 13. FIG. 12 is a diagram in which the blade diameter of the first spiral blade is larger than the blade diameter of the second spiral blade in the first transport member having the first spiral blade using a magnetic material at the tip of the third embodiment. FIG. 13 shows a case where the blade diameter of the first spiral blade is larger than the blade diameter of the second spiral blade in the first transport member having the first spiral blade using a magnetic material at the tip of the third embodiment ( It is a figure which compared the amount of scattering between the example (Example) and the case where the blade diameter of the first spiral blade and the blade diameter of the second spiral blade are the same (comparative example).

この実施例は、上記実施例３の先端に磁性体を用いた第１螺旋羽根を有する第１搬送部材において、第１螺旋羽根の羽根径を、第２螺旋羽根の羽根径よりも大きくしている。他方、実施例３でせん断効果を高めた螺旋羽根でない方を、通常の樹脂材料とすることで搬送機能の低下防ぎ、現像剤の劣化を防止する。 In this embodiment, in the first transport member having the first spiral blade using a magnetic material at the tip of the third embodiment, the blade diameter of the first spiral blade is made larger than the blade diameter of the second spiral blade. There is. On the other hand, by using a normal resin material for the non-spiral blade having an enhanced shearing effect in Example 3, deterioration of the transport function is prevented and deterioration of the developer is prevented.

図１３を参照して、比較例５−１から比較例５−３は、一条スクリューを用いた第１搬送部材において、先端に磁性体でない樹脂を用いた場合を示し、比較例５−４は、一条スクリューを用いた第１搬送部材において、先端に磁性体を用いた場合を示している。比較例５−５は、二条スクリューを用いた第１搬送部材において、第１螺旋羽根の先端に磁性体を有し、第２螺旋羽根の先端は磁性体を有さない樹脂を用いている。構造は、実施例３−１と同じである。 With reference to FIG. 13, Comparative Examples 5-1 to 5-3 show a case where a non-magnetic resin is used at the tip of the first transport member using a single-row screw, and Comparative Example 5-4 shows a case where a resin other than a magnetic material is used at the tip. , The case where a magnetic material is used for the tip of the first transport member using a single-row screw is shown. In Comparative Example 5-5, in the first transport member using the double-row screw, a resin having a magnetic material at the tip of the first spiral blade and a resin having no magnetic material is used at the tip of the second spiral blade. The structure is the same as in Example 3-1.

実施例５−１は、二条スクリューを用いた第１搬送部材において、第１螺旋羽根の先端に磁性体を有し、第２螺旋羽根の先端は磁性体を有さない樹脂を用いている。第１螺旋羽根の最大径は２５．５ｍｍであり、第２螺旋羽根の最大径は２４ｍｍよりも大きく設けられている。この構成によっても、搬送機能の低下防ぎ、現像剤の劣化を防止する。 In Example 5-1, in the first transport member using the double-row screw, a resin having a magnetic material at the tip of the first spiral blade and a resin having no magnetic material is used at the tip of the second spiral blade. The maximum diameter of the first spiral blade is 25.5 mm, and the maximum diameter of the second spiral blade is larger than 24 mm. This configuration also prevents deterioration of the transport function and deterioration of the developer.

（実施例６）
図１４および図１５を参照して、実施例６について説明する。図１４は、上記実施例４の第２螺旋羽根の羽根厚さを第１螺旋羽根の羽根厚さよりも厚くした第１螺旋羽根を有する第１搬送部材において、第２螺旋羽根の羽根径を、第１螺旋羽根の羽根径よりも大きくした図、図１５は、第２螺旋羽根の羽根径を、第１螺旋羽根の羽根径よりも大きくした場合（実施例）と、第１螺旋羽根の羽根径と第２螺旋羽根の羽根径とが同じ場合（比較例）との飛散量を比較した図である。 (Example 6)
The sixth embodiment will be described with reference to FIGS. 14 and 15. FIG. 14 shows the blade diameter of the second spiral blade in the first transport member having the first spiral blade in which the blade thickness of the second spiral blade of the fourth embodiment is thicker than the blade thickness of the first spiral blade. FIG. 15 shows a diagram in which the blade diameter of the first spiral blade is larger than the blade diameter of the first spiral blade when the blade diameter of the second spiral blade is larger than the blade diameter of the first spiral blade (Example). It is a figure which compared the amount of scattering when the diameter and the blade diameter of the 2nd spiral vane are the same (comparative example).

この実施例は、上記実施例４の第２螺旋羽根の羽根厚さを第１螺旋羽根の羽根厚さよりも厚くした第１螺旋羽根を有する第１搬送部材において、第２螺旋羽根の羽根径を、第１螺旋羽根の羽根径よりも大きくしていることで搬送機能の低下防ぎ、現像剤の劣化を防止する。 In this embodiment, the blade diameter of the second spiral blade is set in the first transport member having the first spiral blade in which the blade thickness of the second spiral blade of the fourth embodiment is thicker than the blade thickness of the first spiral blade. By making the diameter of the first spiral blade larger than that of the first spiral blade, deterioration of the transport function is prevented and deterioration of the developer is prevented.

図１５を参照して、比較例６−１から比較例６−３は、一条スクリューを用いた第１搬送部材を用いた場合を示し、比較例６−４は、二条スクリューを用いた第１搬送部材を示し、第１螺旋羽根と第２螺旋羽根との最大径は同じである。構造は、実施例４−１と同じである。 With reference to FIG. 15, Comparative Examples 6-1 to 6-3 show the case where the first transport member using the single-row screw is used, and Comparative Example 6-4 shows the case where the first transport member using the double-row screw is used. The transport member is shown, and the maximum diameters of the first spiral blade and the second spiral blade are the same. The structure is the same as in Example 4-1.

実施例６−１は、二条スクリューを用いた第１搬送部材において、上記実施例４の第２螺旋羽根の最大径を２５．５ｍｍとし、第１螺旋羽根の最大径の２４ｍｍよりも大きくしている。この構成によっても、搬送機能の低下防ぎ、現像剤の劣化を防止する。 In Example 6-1, in the first transport member using the double-row screw, the maximum diameter of the second spiral blade of the fourth embodiment is set to 25.5 mm, which is larger than the maximum diameter of the first spiral blade of 24 mm. There is. This configuration also prevents deterioration of the transport function and deterioration of the developer.

（実施例７）
図１６を参照して、実施例７について説明する。図１６は、第１搬送部材１８の回転軸１８ａの延びる方向に沿って、Ｆｅ系の磁性部材１８ｅが配置され、少なくとも１か所に電磁石９が配置されている状態を示す。この構成によれば、筐体２０と第１搬送部材１８の軸方向との間の全面に磁界が発生する。すなわち、電磁石９の個数を減らし、現像装置および画像形成装置を小型化することができる。 (Example 7)
The seventh embodiment will be described with reference to FIG. FIG. 16 shows a state in which the Fe-based magnetic member 18e is arranged along the extending direction of the rotation shaft 18a of the first conveying member 18, and the electromagnet 9 is arranged at at least one place. According to this configuration, a magnetic field is generated on the entire surface between the housing 20 and the axial direction of the first transport member 18. That is, the number of electromagnets 9 can be reduced, and the developing device and the image forming device can be miniaturized.

（実施例８）
図１７を参照して、本実施例について説明する。図１７は、本実施例の仕切板１０Ａを示す拡大図である。この実施例は、現像装置２の筐体２０内に設置された仕切板１０Ａ（図１参照）が磁性体で構成されている。仕切板１０Ａは、電磁石によって磁化され、筐体２０の下面だけでなく、横面からも磁界を発生させることが可能である。 (Example 8)
The present embodiment will be described with reference to FIG. FIG. 17 is an enlarged view showing the partition plate 10A of this embodiment. In this embodiment, the partition plate 10A (see FIG. 1) installed in the housing 20 of the developing apparatus 2 is made of a magnetic material. The partition plate 10A is magnetized by an electromagnet, and it is possible to generate a magnetic field not only from the lower surface of the housing 20 but also from the lateral surface.

図１７に示すように、磁性体である仕切板１０Ａを筐体２０の外部にまで延長し、延長部分の近傍に電磁石９を設置することで、仕切板１０Ａを容易に磁化させ、筐体２０の横面と第１搬送部材１８および第２搬送部材１９との間にも磁界を発生させることを可能とする。 As shown in FIG. 17, by extending the partition plate 10A, which is a magnetic material, to the outside of the housing 20 and installing an electromagnet 9 in the vicinity of the extension portion, the partition plate 10A can be easily magnetized and the housing 20 can be magnetized. It is possible to generate a magnetic field between the lateral surface of the surface and between the first transport member 18 and the second transport member 19.

以上、本実施の形態および各実施例における現像装置および画像形成装置によれば、トナー補給速度に合わせて現像剤を拘束するため、現像剤にせん断を与えて、効率良く現像剤とトナーと攪拌することを可能とする。その結果、トナー飛散、および、トナーこぼれを抑制することが可能となる。 As described above, according to the developing apparatus and the image forming apparatus in the present embodiment and each embodiment, in order to restrain the developer according to the toner replenishment speed, shear is applied to the developer to efficiently stir the developer and the toner. It is possible to do. As a result, it is possible to suppress toner scattering and toner spillage.

今回開示された実施の形態はすべての点で例示であって制限的なものではないと考えられるべきである。本発明の範囲は上記した説明ではなくて特許請求の範囲によって示され、特許請求の範囲と均等の意味および範囲内でのすべての変更が含まれることが意図される。 It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

１像担持体、２現像装置、３帯電ローラー、４転写ローラー、５クリーニングブレード、６露光装置、８現像領域、９電磁石、９Ａ磁界発生装置、１０，１０Ａ仕切板、１１現像剤担持体、１３現像剤回収領域、１５トナー補給口、１６規制部材、１７現像剤槽、１８第１搬送部材、１８ａ回転軸、１８ｂ１第１螺旋羽根、１８ｂ２第２螺旋羽根、１８ｄ磁性体、１８ｅ磁性部材、１９第２搬送部材、２０筐体、２０ａ第１攪拌路、２０ｂ第２攪拌路、２１ＡＴＤＣセンサー、２２トナー、２３現像剤、２４現像開口、２５磁石ローラー、２６スリーブローラー、９１駆動制御部、９２電源、９３波形信号生成部、９５画像カバレッジ情報、１００画像形成装置。 1 image carrier, 2 developing device, 3 charging roller, 4 transfer roller, 5 cleaning blade, 6 exposure device, 8 developing area, 9 electromagnet, 9A magnetic field generator, 10, 10A partition plate, 11 developer carrier, 13 Developer recovery area, 15 Toner replenishment port, 16 Regulatory member, 17 Developer tank, 18 1st transport member, 18a rotating shaft, 18b1 1st spiral blade, 18b2 2nd spiral blade, 18d magnetic material, 18e magnetic member, 19 2nd transport member, 20 housing, 20a 1st stirring path, 20b 2nd stirring path, 21 ATDC sensor, 22 toner, 23 developer, 24 developing opening, 25 magnet roller, 26 sleeve roller, 91 drive control unit, 92 Power supply, 93 waveform signal generator, 95 image coverage information, 100 image forming apparatus.

Claims

A developing device that uses a two-component developer having toner and a magnetic carrier.
A housing with a developer tank and
A transport member installed in the developer tank and transporting the two-component developer in the developer tank with stirring.
At least one or more magnetic field generating members installed outside the housing and generating a magnetic field between the housing and the transport member.
The drive control unit of the magnetic field generating member is provided.
The magnetic field generating member is an electromagnet and
The transport member includes a rotating shaft and spiral blades provided around the rotating shaft.
The spiral blade contains a magnetic material and contains a magnetic material.
The drive control unit
A developing device that controls the magnetic field generation time of the magnetic field generation member by controlling the operation amount (duty) of the electromagnet according to the toner supply speed to the developer tank.

The magnetic body in a region including the distal end of the helical blade is provided, the developing device according to claim 1.

A developing device that uses a two-component developer having toner and a magnetic carrier.
A housing with a developer tank and
A transport member installed in the developer tank and transporting the two-component developer in the developer tank with stirring.
At least one or more magnetic field generating members installed outside the housing and generating a magnetic field between the housing and the transport member.
The drive control unit of the magnetic field generating member is provided.
The magnetic field generating member is an electromagnet.
The transport member is
Rotation axis and
The first spiral blade and the second spiral blade provided around the rotation axis are included.
Wherein at least one of the first spiral blade and said second spiral blade, magnetic material is provided in a region including the distal end,
The drive control unit
A developing device that controls the magnetic field generation time of the magnetic field generation member by controlling the operation amount (duty) of the electromagnet according to the toner supply speed to the developer tank.

The developing apparatus according to claim 3 , wherein the blade thickness of either the first spiral blade or the second spiral blade is larger than the thickness of the other blade.

The developing apparatus according to claim 3 , wherein the blade diameter of either the first spiral blade or the second spiral blade is larger than the diameter of the other blade.

A developing device that uses a two-component developer having toner and a magnetic carrier.
A housing with a developer tank and
A transport member installed in the developer tank and transporting the two-component developer in the developer tank with stirring.
At least one or more magnetic field generating members installed outside the housing and generating a magnetic field between the housing and the transport member.
The drive control unit of the magnetic field generating member is provided.
The magnetic field generating member is an electromagnet and
Wherein between the housing and the magnetic field generating member, the magnetic member is provided along the extending direction of the conveying member,
The drive control unit
A developing device that controls the magnetic field generation time of the magnetic field generation member by controlling the operation amount (duty) of the electromagnet according to the toner supply speed to the developer tank.

A developing device that uses a two-component developer having toner and a magnetic carrier.
A housing with a developer tank and
A transport member installed in the developer tank and transporting the two-component developer in the developer tank with stirring.
At least one or more magnetic field generating members installed outside the housing and generating a magnetic field between the housing and the transport member.
The drive control unit of the magnetic field generating member is provided.
The magnetic field generating member is an electromagnet and
The developer tank is partitioned by a partition plate arranged along the direction in which the transport member extends.
The partition plate is magnetic, are magnetized by the magnetic field generating member,
The drive control unit
A developing device that controls the magnetic field generation time of the magnetic field generation member by controlling the operation amount (duty) of the electromagnet according to the toner supply speed to the developer tank.

Image carrier and
A developing device, which is arranged to face the image carrier and develops a latent image formed on the image carrier, is provided.
The image forming apparatus, which is the developing apparatus according to any one of claims 1 to 7.