JPS62138876A - Image forming device - Google Patents

Abstract

PURPOSE:To control toner concentration reliably with high accuracy by agitating and conveying a developer for a specific period from operation is started without operating a toner supply means regardless of developer toner concentration information. CONSTITUTION:The developer at a developer storage part is agitated and conveyed by agitating and conveying means 8 and 9 for the specific period after the power source is turned on or from the point of time when the operation of a developing device is started after the power source is turned on without operating the toner supply means regardless of toner concentration information on the developer at the developer storage part which is detected by the developer toner concentration detecting means 15 of a developing device. Namely, the preliminary agitation and conveyance period T of the developer agitating and conveying means 8 and 9 is only set to several - tens of seconds in general as shown in the timing chart of the power-on operation, operation of the developer agitating and conveying means 8 and 9, a toner supply means, and a developing stroke. Further, toner may be supplied without fail not only when the power source is turned on, but also when toner concentration is detected.

Description

【発明の詳細な説明】 イ　発明の目的 〔産業上の利用分野〕 本発明は電子写真装置・静電記録装置等の画像形成装置
に関する。DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention [Field of Industrial Application] The present invention relates to an image forming apparatus such as an electrophotographic apparatus or an electrostatic recording apparatus.

〔従来の技術〕[Conventional technology]

潜像保持体に静電潜像・電位潜像等の潜像を形成し、そ
の潜像を現像して直接式に或は間接式（転写式）に画像
形成物を得る装置は各種の原理・方式のものが提案され
、又実用化されている。Devices that form a latent image such as an electrostatic latent image or a potential latent image on a latent image holder and develop the latent image to obtain an image formed directly or indirectly (transfer type) are based on various principles. - A method has been proposed and put into practical use.

本発明はそのうちの特に、トナーと磁性粒子とからなる
現像剤を現像剤担持部材に担持させ潜像保持体面を現像
する現像装置を具備させた画像形成装置に関する。In particular, the present invention relates to an image forming apparatus equipped with a developing device that causes a developer carrying member to carry a developer consisting of toner and magnetic particles to develop the surface of a latent image carrier.

トナーと磁性粒子からなる現像剤を用いる方式の現像装
置の場合は、現像によって消費されるのはトナー分のみ
であるので、そのままでは現像剤のトナー濃度が次第に
低下していき、形成画像濃度も低下していく結果となる
。トナー消費に拘らず現像剤のトナー濃度を常に適正に
保つ為には。In the case of a developing device that uses a developer consisting of toner and magnetic particles, only the toner is consumed during development, so if left as is, the toner concentration of the developer will gradually decrease, and the density of the formed image will also decrease. This results in a decline. In order to always maintain the appropriate toner concentration in the developer regardless of toner consumption.

現像剤の現在トナー濃度の速やかな検知、その検知値に
もとずくトナー分の適時−適量補給、補給トナー分の現
像剤全体への速やかな均一分散混合及びその現像剤のト
ナー濃度検知部への迅速な搬送が必要である。Quickly detects the current toner concentration of the developer, replenishes the appropriate amount of toner at the appropriate time based on the detected value, quickly and uniformly disperses and mixes the supplied toner into the entire developer, and sends the developer to the toner concentration detection section. rapid transportation is necessary.

そこでこの種の現像装置は、現像剤収納部の現像剤のト
ナー濃度を検知する手段、現像剤収納部の現像剤を撹拌
・搬送状態にする手段、補給トナー収納部、該補給トナ
ー収納部のトナーを現像剤収納部へ搬送する手段を具備
させ、上記のトナー濃度検出手段で現像剤収納部の現像
剤のトナー濃度の経時的低下度合を検知させ、その検知
情報を制御回路へ入力させ、トナー濃度低下が所定の許
容下限になったら上記の補給トナー搬送手段を作動させ
て補給トナー収納部のトナーの一部を現像剤収納部へ導
入させ、その補給トナーは上記の現像剤撹拌・搬送手段
により現像剤収納部の現像剤の全体に速やかに混入分散
させ、トナー補給により現像剤のトナー濃度が所定に上
昇したことが上記のトナー濃度検出手段で検知されたら
補給トナー搬送手段の作動を停止させ、これにより現像
剤のトナー濃度を所定の略一定値に自動管理制御するよ
うになっている。Therefore, this type of developing device has a means for detecting the toner concentration of the developer in the developer storage section, a means for stirring and conveying the developer in the developer storage section, a replenishment toner storage section, and a means for detecting the toner concentration of the developer in the developer storage section. comprising a means for transporting the toner to the developer storage section, causing the toner concentration detection means to detect the degree of decrease over time in the toner concentration of the developer in the developer storage section, and inputting the detected information to the control circuit; When the decrease in toner concentration reaches a predetermined allowable lower limit, the replenishment toner conveying means described above is activated to introduce a portion of the toner in the replenishment toner storage section into the developer storage section, and the replenishment toner is stirred and transported as described above. When the toner concentration detecting means detects that the toner concentration of the developer has increased to a predetermined level due to toner replenishment, the replenishment toner conveying means is activated. As a result, the toner concentration of the developer is automatically controlled to a predetermined substantially constant value.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

而して信頼性のある高精度の上記トナー濃度管理制御を
行わせるための要件の１つとして、トナー濃度検出手段
部に対して現像剤が常に存在して作用していること、又
現像剤収納部に対するトナー補給がなされたとき、その
補給トナーが充分に撹拌・混合された現像剤がトナー濃
度検出手段部に速やかに搬送されて作用することが挙げ
られる。One of the requirements for performing reliable and highly accurate toner concentration management control is that the developer always exists and acts on the toner concentration detection means. When toner is replenished into the storage section, the developer in which the replenished toner is sufficiently stirred and mixed is quickly conveyed to the toner concentration detection means section and acts on the developer.

ところが （ａ）例えば、画像形成装置や内蔵現像装置の保守・点
検・修理等のために現像装置を画像形成装置から抜き出
し、再装着操作したとき１画像形成袋はを移動したとき
などにおいて現像装置や画像形成装置の傾斜・振動等に
起因して現像装置の現像剤収納部内の現像剤に大きな片
寄りを生じ、トナー濃度検出手段部に現像剤が存在しな
いか或は一部分にのみ作用している状態となってしまう
ことが往々あり、これによりトナー濃度管理制御系が誤
作動する。However, (a) For example, when the developing device is removed from the image forming device and reinstalled for maintenance, inspection, repair, etc. of the image forming device or built-in developing device, or when an image forming bag is moved, etc. The developer in the developer storage section of the developing device may be largely uneven due to the tilting or vibration of the image forming device, and the developer may not be present in the toner concentration detection means or may be acting only partially. This often results in the toner density management control system malfunctioning.

（ｂ）又上記のトナー濃度管理制御系が作動して現像剤
収納部にトナーが補給された直後時点、或は該補給トナ
ーが充分に撹拌・混合された現像剤がトナー濃度検出部
に搬送されない時点で、画像形成装置の使用が終了して
電源が切られ、従って現像装置の機構作動が停止される
場合もあり、この場合には次に画像形成装置に電源が投
入されたとき現像装置のトナー濃度検出手段は、前記の
画像形ｒ＆装置の電源が切られた時点で既に現像剤収納
部にトナーが補給されているにも拘らず現像剤トナー濃
度不足を検知している状態にあり、その結果トナー濃度
管理制御系が作動してトナー補給がなされて現像剤収納
部は上記前の分も合せてトナーが過補給状態となる。(b) Immediately after the above-mentioned toner concentration management control system operates and toner is replenished into the developer storage section, or the developer with the replenished toner sufficiently stirred and mixed is transported to the toner concentration detection section. At the point when the image forming apparatus is not used, the power is turned off, and the mechanism of the developing device may be stopped. The toner concentration detection means is in a state where it detects an insufficient developer toner concentration even though toner has already been replenished in the developer storage section at the time when the power of the image forming r& device is turned off. As a result, the toner density management control system operates to replenish toner, and the developer storage section becomes over-supplied with toner including the previous toner.

本発明は」−記のような問題点を解決することを目的と
する。The present invention aims to solve the following problems.

口１発明の構成 〔問題点を解決するための手段〕 本発明は、現像装置として、トナーと磁性粒子とか缶な
るＩＴＪ像剤を１υ像剤Ｊ１３ｎ部廿に粕↓へさせ７？
？像保持体面を現像する現像装置を具備させた画像形成
装置において、画像形成装置に電源が投入された時点か
ら、或は該電源投入後現像装置の作動が開始された時点
から所定の期間は現像装置の現像剤トナー濃度検出手段
により検知される現像剤収納部の現像剤トナー濃度情報
の如何に拘らずトナー補給手段は作動させず、現像剤収
納部の現像剤の撹拌・搬送手段による撹拌・搬送を実行
させる。ことを特徴とする画像形成装置を要旨とする。1. Structure of the Invention [Means for Solving the Problems] The present invention is a developing device in which an ITJ developer such as toner and magnetic particles is turned into dregs in a 1υ developer J13n section.7?
? In an image forming apparatus equipped with a developing device that develops the surface of an image carrier, the developing device does not perform development for a predetermined period from the time when the power is turned on to the image forming apparatus, or from the time when the developing device starts operating after the power is turned on. Regardless of the developer toner concentration information in the developer storage section detected by the developer toner concentration detection means of the device, the toner replenishing means is not operated, and the developer in the developer storage section is not stirred or stirred by the conveying means. Execute the transport. The gist of the present invention is an image forming apparatus characterized by the following.

〔作　用〕[For production]

上記のように構成することにより、に記の期間中に。 By arranging as above, during the period mentioned above.

■現像剤収納部の現像剤が前記（ａ）項のような原因で
片寄り状態にあっても現像剤撹拌・搬送手段の作動によ
りその片寄り現像剤が現像剤収納部の各部に搬送されて
各部に略均−に分布存在した状態にならされ、トナー濃
度検出手段部にも現像剤が充分に作用した状態になる。■Even if the developer in the developer storage section is unevenly distributed due to the reasons mentioned in item (a) above, the uneven developer is transported to each part of the developer storage section by the operation of the developer stirring/conveying means. The developer is distributed approximately evenly in each part, and the developer is sufficiently applied to the toner concentration detection means.

■又前記（ｂ）項のような場合も現像剤撹拌争搬送手段
の作動により、ｆ！ｊ：、に補給されているトナー分の
現像剤中への撹拌・混合が充分になされ、その現像剤が
トナー濃度検出手段部に作用した状態となる。■Also, in the case of item (b) above, f! The toner replenished in j: is sufficiently stirred and mixed into the developer, and the developer is in a state where it acts on the toner concentration detection means.

而して、上記の期間経過後にトナー濃度管理制御系が正
規に作動可能な状態に保たれ、上記の期間経過時点でト
ナー濃度検出手段が現像剤のトナー濃度不足を検知して
いればその時点でトナー補給手段の動作がなされてトナ
ー補給が行われる。以後トナー濃度検出手段のトナー濃
度検出情報に基づいてトナー補給手段の間欠的な作動が
なされて現像剤のトナー濃度が常に所定の略一定濃度に
維持管理される。If the toner concentration management control system is maintained in a normally operable state after the above-mentioned period has elapsed, and the toner concentration detection means detects an insufficient toner concentration in the developer at the time when the above-mentioned period has elapsed, then The toner replenishing means is activated to replenish toner. Thereafter, the toner replenishing means is operated intermittently based on the toner concentration detection information of the toner concentration detecting means, so that the toner concentration of the developer is always maintained at a predetermined substantially constant concentration.

従って前記（ａ）項や（ｂ）項のような原因によるトナ
ー濃度管理制御系の誤作動が厳に防止され、信頼性のあ
る高精度のトナー濃度管理制御が実行される。Therefore, malfunctions of the toner concentration management control system due to causes such as those described in (a) and (b) above are strictly prevented, and reliable and highly accurate toner concentration management control is executed.

尚、と記の期間経過までは潜像の現像行程は実行させな
い方が望ましい。Incidentally, it is preferable that the latent image development step is not performed until the period indicated by .

〔実施例〕〔Example〕

第１図は画像形成装置の一例の概略図、第２図は該装置
に具備させた、トナーと磁性粒子からなる現像剤を用い
る方式の現像装置の一例の横断側面図である。FIG. 1 is a schematic view of an example of an image forming apparatus, and FIG. 2 is a cross-sectional side view of an example of a developing device that uses a developer made of toner and magnetic particles, which is included in the image forming apparatus.

′ＦｔＳ１図において、Ａは潜像保持体としてのドラム
（電子写真における感光体、静電記録における誘電体等
）であり、軸１００を中心に矢示方向に所定の周速度で
回転駆動される。Ｃはそのドラム周面に）！像を形成す
る潜像形成機器部、Ｂは潜像を現像する現像９置、Ｄは
その現像像を転写材Ｐに転写する転写装置である。転写
装はにより現像像の転写を受けた転写材ＰはドラムＡ面
から順次に剥離されて定着装置Ｅへ導入されて像定着を
受は画像形成物として機外へ排出される。像転写後のド
ラムＡ面はクリーナＦで清浄化され、繰り返して画像形
成に供される。' In the FtS1 diagram, A is a drum (a photoreceptor in electrophotography, a dielectric in electrostatic recording, etc.) as a latent image holding body, and is driven to rotate at a predetermined circumferential speed in the direction of the arrow around the shaft 100. . C is on the drum circumference)! A latent image forming equipment section for forming an image, B a developing device 9 for developing a latent image, and D a transfer device for transferring the developed image onto a transfer material P. The transfer material P to which the developed image has been transferred by the transfer device is sequentially peeled off from the surface of the drum A, introduced into the fixing device E, where the image is fixed, and then discharged outside the machine as an image-formed product. After the image has been transferred, the surface of the drum A is cleaned by a cleaner F, and is repeatedly used for image formation.

第２図の現像装置Ｂにおいて、■は現像容器であって、
内部を隔壁２によってトナー収納部３と、トナーと磁性
粒子からなる現像剤を収納する現像剤収納部４とに区画
されている。トナー収納部３内の収納トナー、及び現像
剤収納部４内の現像剤は図には省略した。トナー収納部
３内の収納トナーはトナー搬送部材６．・６２が回動駆
動されることにより逐次隔壁２方向に搬送され、トナー
補給口１６から現像剤収納部４内へ補給される。In the developing device B in FIG. 2, ■ is a developing container,
The interior is divided by a partition wall 2 into a toner storage section 3 and a developer storage section 4 that stores a developer made of toner and magnetic particles. The toner stored in the toner storage section 3 and the developer in the developer storage section 4 are omitted from the drawing. The stored toner in the toner storage section 3 is transferred to the toner conveying member 6. - By rotationally driving the toner 62, the toner is sequentially conveyed in the direction of the partition wall 2, and is replenished into the developer storage portion 4 from the toner replenishment port 16.

７は現像剤収納部４内に配設した現像剤担持部材であり
、マグネットロール７２を内蔵した非磁性物質でできた
現像スリーブ７Ｉで構成されている。該現像スリーブ７
、は右斜め下面部が現像剤収納部４に設けた開口部から
外部に露呈しており、現像装置Ｂは現像スリーブ７１の
上記外部露呈面部が潜像保持体Ａ面に対して所定の径小
な隙間を存して対向位置するように支持部材に位置決め
保持されている。Reference numeral 7 denotes a developer carrying member disposed within the developer accommodating portion 4, which is composed of a developing sleeve 7I made of a non-magnetic material and having a built-in magnet roll 72. The developing sleeve 7
, the diagonally lower right surface portion is exposed to the outside from the opening provided in the developer storage section 4, and the developing device B has the externally exposed surface portion of the developing sleeve 71 at a predetermined diameter with respect to the surface of the latent image holder A. They are positioned and held on the support member so that they are opposite to each other with a small gap between them.

Ｓ、−３３，Ｎ、〜Ｎ３はマグネットロール７□の着磁
位置を示している。マグネットロール７□は両端部を固
定支持されていて回転せず、その外側の現像スリーブ７
、がマグネットロール７２の囲りを所定の周速で矢印方
向に回転駆動される。S, -33, N, to N3 indicate the magnetized position of the magnet roll 7□. The magnet roll 7□ is fixedly supported at both ends and does not rotate, and the developing sleeve 7 on the outside
, is driven to rotate around the magnet roll 72 at a predetermined circumferential speed in the direction of the arrow.

８・９は現像剤収納部４内において、現像スリーブ７１
とほぼ並行に上下に配設した現像剤撹拌・搬送手段とし
てのスクリュ軸であり、それぞれ矢印方向に回転駆動さ
れている。１７は該上下のスクリュ軸８・９の間に設け
た現像剤循環規制部材である。8 and 9 are the developing sleeves 71 in the developer storage section 4.
Screw shafts are disposed vertically in parallel with the developer agitation and conveyance means, and are driven to rotate in the directions of the arrows. Reference numeral 17 denotes a developer circulation regulating member provided between the upper and lower screw shafts 8 and 9.

１０・１４は現像剤収納部４内の上下部に配設した現像
スリーブ７１周面上の現像剤の循環領域指定部材、１１
・１３は現像剤収納部４の底面と現像スリーブ７、下面
との隙間部から収、納現像剤が潜像保持体へ方向へ流動
漏洩することを防止するべく現像剤収納部４の底面側に
配設した磁性部材とマグネット、１２は現像スリーブ７
１の周面に形成する現像剤の層厚を規制するために、現
像スリーブ７、の上面側に下辺を現像スリーブ上面に対
して所定の径小の隙間を存して対向させて配設した非磁
性ブレードである。Reference numerals 10 and 14 designate developer circulation area designation members on the circumferential surface of the developing sleeve 71 disposed at the upper and lower parts of the developer storage section 4;
・13 is stored from the gap between the bottom surface of the developer storage section 4 and the lower surface of the developing sleeve 7, and is installed on the bottom side of the developer storage section 4 in order to prevent the stored developer from flowing and leaking in the direction toward the latent image holder. 12 is a developing sleeve 7.
In order to regulate the layer thickness of the developer formed on the circumferential surface of the developing sleeve 1, the developing sleeve 7 is disposed on the upper surface side with its lower side facing the upper surface of the developing sleeve with a gap of a predetermined small diameter. It is a non-magnetic blade.

１５は現像剤収納部４内の現像剤の濃度（トナーと磁性
粒子との混合比）を検知するセンサであり、このセンサ
の出力が制御回路（不図示）へ入力され、それに応じて
前記トナー収納部３内のトナー搬送部材６．＠６２の回
動駆動が制御される。Reference numeral 15 denotes a sensor that detects the concentration of the developer (mixing ratio of toner and magnetic particles) in the developer storage section 4. The output of this sensor is input to a control circuit (not shown), and the toner is adjusted accordingly. Toner transport member 6 in storage section 3. The rotational drive of @62 is controlled.

現像装置稼動時は現像スリーブ７１、スクリュ軸８−９
はそれぞれ所定の速度で回転駆動され、現像スリーブ７
１と潜像保持体Ａの間にはバイアス電源Ｓにより交番電
圧が印加される。When the developing device is in operation, the developing sleeve 71 and the screw shaft 8-9
are each rotated at a predetermined speed, and the developing sleeve 7
An alternating voltage is applied between the latent image holding member A and the latent image holding member A by a bias power supply S.

スクリュ軸８・９の回転により現像剤収納部４内の現像
剤は現像スリーブ７１の長手方向に十分撹拌され、現像
スリーブ７１付近ではほぼ均一なトナーと磁性粒子の混
合比が得られ、実質的に現像スリーブ７Ｉの長手方向各
部についてのムラが除去される。Due to the rotation of the screw shafts 8 and 9, the developer in the developer storage section 4 is sufficiently stirred in the longitudinal direction of the developing sleeve 71, and a substantially uniform mixing ratio of toner and magnetic particles is obtained near the developing sleeve 71. The unevenness in each longitudinal portion of the developing sleeve 7I is removed.

スクリュ軸８・９は夫々矢印の方向に回転するが、それ
により現像剤収納部４内の現像剤が上側のスクリュ軸８
近傍の現像剤と下側のスクリュ軸９近傍の現像剤とが夫
々のスクリュ軸の長手方向に対して反対方向に搬送され
るように上下のスクリュ軸８・９のスクリュ羽根の向き
を夫々逆向きに設定しである。The screw shafts 8 and 9 each rotate in the direction of the arrow, and as a result, the developer in the developer storage section 4 is transferred to the upper screw shaft 8.
The directions of the screw blades of the upper and lower screw shafts 8 and 9 are reversed so that the nearby developer and the developer near the lower screw shaft 9 are transported in the opposite direction to the longitudinal direction of each screw shaft. It is set in the direction.

更に本例の装置においては上側のスクリュ軸８と下側の
スクリュ軸９の夫々の＠長手方向への現像剤搬送力は、
下側スクリュ軸９の方が相対的に大きくなるように、七
記両スクリュ軸８争９のスクリュ羽根についての長さ・
間隔を前者８よりも後者９の方が大きい関係に設定しで
ある。Furthermore, in the apparatus of this example, the developer conveying force in the longitudinal direction of the upper screw shaft 8 and the lower screw shaft 9 is as follows.
The lengths of the screw blades of both screw shafts 8 and 9 described in 7 above are adjusted so that the lower screw shaft 9 is relatively larger.
The interval is set so that the latter 9 is larger than the former 8.

現像剤収納部４内における現像剤の現像剤収納部横断面
上での動きは、現像スリーブ７□の回転、スクリュ軸８
・９の回転、マグネットロール７２の磁界、現像剤循環
領域指定部材１０・１４、同循項規制部材１７の存在、
現像スリーブ７１と現像剤との摩擦力、現像剤の重力等
により第１図の白抜き矢示の如き循環的流動運動となる
。The movement of the developer in the developer storage section 4 on the cross section of the developer storage section is caused by the rotation of the developing sleeve 7□ and the screw shaft 8.
9, the magnetic field of the magnet roll 72, the presence of the developer circulation area designating members 10 and 14, and the circulation regulating member 17;
Due to the frictional force between the developing sleeve 71 and the developer, the gravity of the developer, etc., a cyclical flow motion as shown by the white arrow in FIG. 1 occurs.

而して現像剤収納部４の現像剤溜り内に臨んでいる現像
スリーブ７１の面領域にその近傍の現像剤即ちトナーを
含む磁性粒子がスリーブ７、内のマグネットロール７２
の磁力により磁気ブラシ吸着層として付着保持されて現
像スリーブ７１の回転に伴ない非磁性ブレード１２位置
へ搬送され、非磁性ブレード１２位置を通過する過程で
層厚が規制され、トナーを含む少量の磁性粒子の薄層と
なって現像部ａ（潜像保持体Ａと現像スリーブ７１の対
面部、磁極Ｎ２付近）を通過する。As a result, magnetic particles containing the developer, that is, toner, in the vicinity of the surface area of the developing sleeve 71 facing into the developer reservoir of the developer storage section 4 are transferred to the magnetic roll 72 inside the sleeve 7.
It is adhered and held as a magnetic brush adsorption layer by the magnetic force of the developing sleeve 71, and is transported to the non-magnetic blade 12 position as the developing sleeve 71 rotates.The layer thickness is regulated during the process of passing through the non-magnetic blade 12 position, and a small amount of toner containing The magnetic particles become a thin layer and pass through the developing section a (the facing portion of the latent image holder A and the developing sleeve 71, near the magnetic pole N2).

その現像部ａの通過過程において現像部ａに作用してい
る電界、磁極Ｎ２の磁界作用により、現像スリーブ７１
側の現像剤層のトナーが潜像保持体Ａ面側に潜像パター
ンに対応して移行付着して潜像保持体Ａ面の潜像のトナ
ー現像が順次に行われる。During the process of passing through the developing section a, the developing sleeve 71
The toner in the developer layer on the side moves and adheres to the side A of the latent image carrier in accordance with the latent image pattern, and the toner development of the latent image on the side A of the latent image carrier is sequentially performed.

現像に供され、現像部ａを通過した現像スリーブ７□側
の現像剤層は引続く現像スリーブ７１の回動により現像
剤収納部４内に、磁極Ｓ２・Ｎ２の磁界によりそのまま
スリーブ７、面に保持されて戻し搬送されて現像剤収納
部４内の現像剤と混り合う。The developer layer on the side of the developing sleeve 7□ that has been subjected to development and has passed through the developing section a is transferred into the developer storage section 4 by the subsequent rotation of the developing sleeve 71, and is transferred to the sleeve 7 and the surface by the magnetic fields of the magnetic poles S2 and N2. The developer is held by the developer storage unit 4 and transported back to mix with the developer in the developer storage section 4 .

現像剤収納部４の現像剤内のトナー分は潜像の現像に消
費されることにより経時的に磁性粒子との混合比が低下
していく。その低下度合がセンサ１５により検知されそ
の検知情報が制御回路（不図示）に入力され、低下度が
所定の許容下限になるとその信号によりトナー収納部３
内のトナー供給部材６□　・６２の回転がなされ、これ
によりトナー収納部３内のトナーがトナー補給口１６か
ら現像剤収納部４内へ逐次導入補給される。The toner in the developer in the developer storage section 4 is consumed in developing the latent image, so that the mixing ratio with the magnetic particles decreases over time. The degree of decrease is detected by the sensor 15, and the detected information is input to a control circuit (not shown). When the degree of decrease reaches a predetermined allowable lower limit, a signal is sent to the toner storage section 3.
The inner toner supply members 6□ and 62 are rotated, whereby the toner in the toner storage section 3 is sequentially introduced and replenished into the developer storage section 4 from the toner supply port 16.

補給されたトナーは現像剤収納部４内の現像剤内に下記
のように取り込まれて現像剤の全体に均−會迅速に混入
していく。このトナー補給により現像剤収納部４内の現
像剤のトナー分混合比が上昇し所定の許容上昇になった
ことがセンサ１５により検知されると、トナー補給部材
６１　・６２の回転駆動が停止される。これにより現像
剤収納部４内の現像剤の磁性粒子に対するトナー分の混
合比が常に略一定に保たれ、常に安定した高画質画像を
得ることができる。The replenished toner is taken into the developer in the developer storage section 4 as described below, and is evenly and quickly mixed into the entire developer. When the sensor 15 detects that the toner mixing ratio of the developer in the developer storage section 4 has increased to a predetermined allowable increase due to this toner replenishment, the rotational drive of the toner replenishing members 61 and 62 is stopped. Ru. As a result, the mixing ratio of the toner to the magnetic particles of the developer in the developer storage section 4 is always kept substantially constant, and a stable high-quality image can always be obtained.

即ちトナー補給口１６から現像剤収納部４内に補給され
るトナーは下側のスクリュ軸９によって既存の現像剤内
に軸方向に移動しながら撹拌・搬送されて混合分散され
る。そしてその現像剤は現像スリーブ７１上を移動し、
循環規制部材１７と磁極Ｓ３との間で循環が規制され、
潜像保持体Ａを現像し終えて現像剤収納部４内に戻し搬
送されたスリーブ７１上の現像剤、及びスクリュ軸８に
より搬送された現像剤と合流して混合撹拌され、一部は
スクリュ軸８の方向へ一部は上側の現像剤循環領域指定
部材１０を通って非磁性ブレード１２側へ流動して層厚
規制を受は現像スリーブ７１上に保持されて現像部ａへ
搬送され、潜像の現像に供される。スクリュ軸８方向へ
搬送された現像剤は、該スクリュ軸８の軸方向へスクリ
ュ軸９とは反対方向に搬送されながら一部はスリーブ方
向へ、一部はスクリュ軸９の方向へと搬送される。That is, the toner supplied into the developer storage portion 4 from the toner supply port 16 is stirred and conveyed by the lower screw shaft 9 while moving in the axial direction into the existing developer, and is mixed and dispersed. Then, the developer moves on the developing sleeve 71,
Circulation is regulated between the circulation regulating member 17 and the magnetic pole S3,
After developing the latent image holder A, the developer on the sleeve 71 returned to the developer accommodating portion 4 and the developer transported by the screw shaft 8 are mixed and stirred. A part of the developer flows in the direction of the shaft 8 through the upper developer circulation area specifying member 10 to the non-magnetic blade 12 side, where the layer thickness is regulated and is held on the developing sleeve 71 and conveyed to the developing section a. Provided for developing the latent image. The developer transported in the direction of the screw shaft 8 is transported in the axial direction of the screw shaft 8 in the opposite direction to the screw shaft 9, with some of the developer being transported toward the sleeve and some of it toward the screw shaft 9. Ru.

スクリュ軸８によって軸方向へ移動する際にスリーブ７
１表面の現像剤は軸方向にわたってほぼ均一にならされ
る。When the sleeve 7 is moved in the axial direction by the screw shaft 8,
The developer on one surface is almost uniformly distributed in the axial direction.

現像剤循環規制部材１７は、スリーブ７、側では磁極Ｓ
３付近の現像剤の循環・搬送を規制すると共に、スクリ
ュ軸８或は同９に対してはガイド板の役割を果し、現像
剤の撹拌・搬送の安定化にもＳ与している。又スリーブ
７Ｉと反対側においては現像容器１との間に空隙を有し
、スクリュ軸８により循環・搬送された現像剤の一部を
スクリュ軸９の方向へ導く作用もしている。The developer circulation regulating member 17 has a sleeve 7 and a magnetic pole S on the side.
In addition to regulating the circulation and transport of the developer near the screw shaft 3, it also serves as a guide plate for the screw shaft 8 or 9, and also contributes to stabilizing the stirring and transport of the developer. Further, on the opposite side from the sleeve 7I, there is a gap between the developer container 1 and the developer container 1, which functions to guide a portion of the developer circulated and conveyed by the screw shaft 8 toward the screw shaft 9.

現像剤循環規制部材１７はスリーブ７□側の先端に磁性
部材１８を設けると、磁極Ｓ３との間に磁界が発生し、
該磁極Ｓ３付近のスリーブ７１の上の現像剤の循環をよ
り強く規制することができる。尚該磁性部材１８はマグ
ネットにしてもよいし、現像剤循環規制部材１７自体を
磁性体で構成することも可能である。マグネットを使用
する場合は磁極Ｓ３と異極ならば現像剤循環の規制が強
まり、同極の場合は循環が良くなり、スリーブ７Ｉ上の
現像剤と現像剤収納部４内の現像剤の入れ替りが良くな
ることが観察された。When the magnetic member 18 is provided at the tip of the developer circulation regulating member 17 on the sleeve 7□ side, a magnetic field is generated between it and the magnetic pole S3.
The circulation of the developer on the sleeve 71 near the magnetic pole S3 can be more strongly regulated. The magnetic member 18 may be a magnet, or the developer circulation regulating member 17 itself may be made of a magnetic material. When using a magnet, if the magnetic pole is different from the magnetic pole S3, the regulation of developer circulation will be strengthened, and if the magnetic pole is the same, the circulation will be improved, and the exchange of the developer on the sleeve 7I and the developer in the developer storage section 4 will be improved. It was observed that it improved.

本例装置におけるトナー濃度検知センサ１５は、現像ス
リーブ７夏に印加した交番電界で誘起されるセンサ電圧
が該センサに作用する現像剤のトナーと磁性粒子との混
合比（即ち現像剤のトナー濃度）により変化してセンナ
出力となる構成のもので、スクリュ軸９で搬送された現
像剤がトナーと磁性粒子との混合比により体積が変化し
てセンサ１５を覆い、その混合比に対向して上記のセン
サ電圧が変化してセンサ出力となる。そのセンナ出力が
現像剤の現在トナー濃度情報として制御回路へ入力され
る。The toner concentration detection sensor 15 in this example device is configured such that a sensor voltage induced by an alternating electric field applied to the developing sleeve 7 acts on the sensor at a mixing ratio of the toner and magnetic particles of the developer (i.e., the toner concentration of the developer). ), the volume of the developer conveyed by the screw shaft 9 changes depending on the mixing ratio of toner and magnetic particles, covering the sensor 15, and the volume changes depending on the mixing ratio of toner and magnetic particles. The above sensor voltage changes and becomes the sensor output. The senna output is input to the control circuit as current toner concentration information of the developer.

センサ１５としては圧電素子、インダクタンス変化検知
素子、交番バイアスを利用したアンテナ方式等を利用す
ることができる。As the sensor 15, a piezoelectric element, an inductance change detection element, an antenna system using an alternating bias, etc. can be used.

第３図（ａ）及び　（ｂ）は夫々、画像形成袋（冴の電
源投入、現像剤撹拌・搬送手段８・９の作動、トナー補
給手段、現像行程のタインミングチャート例である。FIGS. 3(a) and 3(b) are examples of timing charts for turning on the image forming bag (sae), operating the developer stirring/conveying means 8 and 9, toner replenishing means, and the developing process, respectively.

現像剤の撹拌・搬送手段８φ９による予備撹拌・搬送期
間Ｔは一般には数秒〜数１０秒程度に設定すればよい。The preliminary stirring/transporting period T by the developer stirring/transporting means 8φ9 may generally be set to about several seconds to several tens of seconds.

更にＴｉ、源投入時にのみ限らずトナー濃度検知の前に
必ず行っても良い。Furthermore, Ti may be performed not only when turning on the power but also before detecting the toner concentration.

品１−．ｔＦ、”ｌＺ鳩例においで凹抄翔１滑坤・聯１
手工）ンしてのスクリュ軸８・９、現像スリーブ７Ｉの
回転方向は実施例のものに限定されるものではない。Item 1-. tF, "lZ pigeon example in the concave sho 1 slip kon・ren 1
The rotating directions of the screw shafts 8 and 9 and the developing sleeve 7I are not limited to those in the embodiment.

また、撹拌・搬送手段８・９はスクリュ軸に限らず回転
羽根でも良い、マグネットロール７２の磁極数、磁極種
も実施例に限られるものではない。Further, the stirring/conveying means 8 and 9 are not limited to screw shafts, and may be rotary blades, and the number and type of magnetic poles of the magnet roll 72 are not limited to those in the embodiments.

ハ、発明の効果 以上本発明によれば、トナー濃度管理制御が信１イ１性
よく高精度に実行されて安定した高画質の画像形成物を
（ν）ることができ、所期の目的が達成される。C. Effects of the Invention According to the present invention, toner concentration management control can be performed with high reliability and high precision, and stable high-quality image formation (v) can be achieved, thereby achieving the intended purpose. is achieved.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は画像形成装置の一例の概略構成図、第２図は現
、像装置の一例の横断側面図、第３図　（ａ）・（ｂ）
は夫々タイミングチャート例である。 Ａは潜像保持体、Ｂは現像装置、７．は現像剤１ｕ持部
材としての現像スリーブ、８・９は現像剤撹拌番搬送手
段としてのスクリュ軸、１５はトナー濃度検出センサ。Figure 1 is a schematic configuration diagram of an example of an image forming apparatus, Figure 2 is a cross-sectional side view of an example of an image forming apparatus, and Figure 3 (a) and (b).
are examples of timing charts. A is a latent image holding body, B is a developing device, 7. Reference numeral 1 denotes a developing sleeve as a developer holding member, 8 and 9 screw shafts as developer stirring and conveying means, and 15 a toner concentration detection sensor.

Claims (1)

【特許請求の範囲】[Claims] （１）現像装置として、トナーと磁性粒子とからなる現
像剤を現像剤担持部材に担持させ、潜像保持体面を現像
する現像装置を具備させた画像形成装置において、 画像形成装置に電源が投入された時点から、或は該電源
投入後現像装置の作動が開始された時点から所定の期間
は現像装置の現像剤トナー濃度検出手段により検知され
る現像剤収納部の現像剤トナー濃度情報の如何に拘らず
トナー補給手段は作動させず、現像剤収納部の現像剤の
撹拌・搬送手段による撹拌・搬送を実行させる、 ことを特徴とする画像形成装置。(1) In an image forming apparatus equipped with a developing device that develops the surface of a latent image carrier by carrying a developer consisting of toner and magnetic particles on a developer carrying member, power is turned on to the image forming device. For a predetermined period from the time when the power is turned on or from the time when the operation of the developing device is started, the developer toner concentration information in the developer storage section detected by the developer toner concentration detection means of the developing device is determined. An image forming apparatus characterized in that, regardless of the above, the toner replenishing means is not operated, and the developer in the developer storage section is stirred and transported by the stirring and transporting means.