JPS6097368A - Automatic control method of copy density in copying machine - Google Patents

Automatic control method of copy density in copying machine

Info

Publication number
JPS6097368A
JPS6097368A JP58205027A JP20502783A JPS6097368A JP S6097368 A JPS6097368 A JP S6097368A JP 58205027 A JP58205027 A JP 58205027A JP 20502783 A JP20502783 A JP 20502783A JP S6097368 A JPS6097368 A JP S6097368A
Authority
JP
Japan
Prior art keywords
density
control
signal
deviation
toner
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP58205027A
Other languages
Japanese (ja)
Inventor
Michio Murata
道雄 村田
Yoshifumi Hirayama
平山　慶文
Noboru Asaka
浅香　昇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujifilm Business Innovation Corp
Original Assignee
Fuji Xerox Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fuji Xerox Co Ltd filed Critical Fuji Xerox Co Ltd
Priority to JP58205027A priority Critical patent/JPS6097368A/en
Publication of JPS6097368A publication Critical patent/JPS6097368A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/50—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control
    • G03G15/5033—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control by measuring the photoconductor characteristics, e.g. temperature, or the characteristics of an image on the photoconductor
    • G03G15/5041—Detecting a toner image, e.g. density, toner coverage, using a test patch
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00—Apparatus for electrophotographic processes
    • G03G2215/00025—Machine control, e.g. regulating different parts of the machine
    • G03G2215/00029—Image density detection
    • G03G2215/00033—Image density detection on recording member
    • G03G2215/00037—Toner image detection
    • G03G2215/00042—Optical detection

Abstract

PURPOSE:To prevent excessive density control in case of partial trouble of a control system or the like by not performing density control if the deviation of the density of a trial stuck toner from a reference value is larger than the deviation of an abnormal density signal. CONSTITUTION:The density of the toner stuck to a photosensitive drum 2 on trial before copying is detected by a density reading sensor 13, and the detection signal and a reference signal are compared with each other by an arithmetic amplifier 14, and a toner supply motor driving circuit 17 and a developing bias voltage generator 18 are controlled through a control circuit 16 to control automatically the copy density. Meanwhile, the detection signal of the sensor 13 is compared with the abnormal density signal by a comparator 31. If the deviation of the detection signal from the reference signal is larger than that of the abnormal density signal from the reference signal, the circuit 16 is operated in accordance with the output of the comparator 31, and density control due to the circuit 17 and the generator 18 is not performed. Consequently, excessive control is prevented when a part of the control system such as the density reading sensor or the lie is faulty.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、複写機の複写濃度自動ｆｌｉ制御方法にＷ４
する。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to a copy density automatic fli control method for a copying machine.
do.

従来技術 一般に、複写機は、その件部Ｋ　ＩＹ時第化があり、例
えば、トナー供給の不足、ηマ像バイアスの電圧の変動
などでコピーの０度が変化する。従って、上記λつのフ
ァクタを自動制御方式で制御１し、この制御を使方動作
の前、あるいは使方動作と蚊写動作の間でなすことが望
ましい。上記Ｄ［望の割病ｌをなす自動複写濃度制御に
おいては、通常実際の複写動作の前に試し複写を行なう
が、このために消費されるトナー預は膨大なものとなる
。そこで本出願人は、特ｇＦ４昭左ｇ−，２３θ１１．
？号において、感光ドラム上の梗く一部の表面部分、例
えば！ｒＣＴｒＩＸ７ｃ＋＋＋の面積の表面部分を選定
し、この表面部分のみにトナーを試行付着し、このｒ／
％度を検出するようにして、複写濃度検出の際のトナー
消費μを抑えるよ５Ｋｌだ複写Ｗ−の浩度自動制御方法
を捉案した。すなわち、この特許公開公報に開示された
複写機の濃度自動制御方法は、複写機の複写操作の前に
一時的に露光ランプからの光の光量を所定量減じ、この
光により感光ドラム上に一定の小面積の帯電部を残し、
この帯電部にトナーを試行付着させ、この付着濃度を感
光ドラム周面に配置した濃度読取りセンサで臥み取り濃
度信号を得、この濃度信号を予め定めた基準濃度に基づ
く基僧電圧と演１９増幅器により比較し、その出力によ
って現像バイアス電圧およびトナー供給用を制御するも
のである。BACKGROUND OF THE INVENTION In general, copying machines have a tendency to change in time. For example, the 0 degree of copying changes due to insufficient toner supply, fluctuations in the voltage of the η image bias, etc. Therefore, it is desirable to control the above-mentioned λ factors by an automatic control method, and to perform this control before the usage operation or between the usage operation and the mosquito copying operation. In automatic copying density control, which forms part of the above D, a trial copy is usually made before the actual copying operation, but this consumes a huge amount of toner deposits. Therefore, the present applicant proposed the special gF4 Showa g-, 23θ11.
? In this issue, some surface areas on the photosensitive drum, for example! Select a surface area with the area of rCTrIX7c+++, apply toner only to this surface area, and apply this r/
A method for automatically controlling the extent of copying W- was devised to suppress the toner consumption .mu. during copying density detection by detecting the % degree. In other words, the automatic density control method for a copying machine disclosed in this patent publication temporarily reduces the amount of light from an exposure lamp by a predetermined amount before copying operation of the copying machine, and uses this light to produce a constant amount of light on the photosensitive drum. leaving a small charged area of
Toner is trial-adhered to this charging part, and this adhesion density is measured by a density reading sensor placed on the circumferential surface of the photosensitive drum to obtain a density signal. The comparison is made using an amplifier, and the developing bias voltage and toner supply are controlled based on the output thereof.

この濃度制御方法によれば、少ないトナーを用いて複写
濃度検出を行なうことができ経済的であるが、制御系が
故障した場合には、かえって望ましくない事態となる。According to this density control method, copy density detection can be performed using a small amount of toner, which is economical, but if the control system breaks down, an undesirable situation arises.

すなわち、上記制御方法においては、旋光ランプからの
光の光計を露光減衰板を用いて一時的に減じているが、
例えば、この露光減衰板を一時的に光路に駆動するソレ
ノイドが故障した場合は、感光ドラム上に上記帯電部を
残すことが不可能となり、このため上記演算増幅器は“
薄すぎ”信号を出力するよ５になり、制御系は、この信
号に基づいて複写濃度を制御するため、過剰の濃度制御
をしてしまうようになる。また、上記濃度読取りセンサ
が故障した場合にも、制御系が過剰の濃度制御を行なっ
てしまうようになる。That is, in the above control method, the light intensity of the light from the polarizing lamp is temporarily reduced using the exposure attenuation plate.
For example, if the solenoid that temporarily drives this exposure attenuation plate into the optical path fails, it becomes impossible to leave the charged portion on the photosensitive drum, and therefore the operational amplifier
The control system outputs a "too thin" signal, and the control system controls the copy density based on this signal, resulting in excessive density control.Also, if the density reading sensor fails In this case, the control system ends up performing excessive concentration control.

発明の目的 そこで本発明は、制御系の一部が故障した場合Ｋ、過剰
の濃度制御が行なわれないようにすることのできる橡写
根の複写濃度自動制御方法をＰｔ供することを目的とす
るものである。OBJECT OF THE INVENTION Therefore, an object of the present invention is to provide an automatic copy density control method for cypress copying that can prevent excessive density control from being performed in the event of a failure in a part of the control system. It is something.

発明の構成 本発明による複写機の他方濃度自動制御方法は、上記し
たタイプの複写濃度自動制御方法において、上記した目
的を達成するため、上記濃度信号を、上記基準電圧から
所定値ずれた異常濃度信号と比較器で比較し、上記濃度
信号の上記基Ａ′Ｊ電圧からの偏差が、上記異常濃度信
号の上記基準１１１：圧がらの偏差より大きいとき、上
記濃度制御を行なわないようにしたことを制御とするも
のである。すなわち、本発明の複写濃度自動制御方法に
おいては、上記一つの偏差を比較することによって、制
御系の故障を検出し、この故障検出の際に制御を停止す
るようＫしたので、制御系の故障による複写濃度の過剰
制御を回避することができる。Structure of the Invention The present invention provides an automatic density control method for copying machines of the type described above, in which the density signal is adjusted to an abnormal density that is deviated from the reference voltage by a predetermined value. When the signal is compared with the comparator and the deviation of the concentration signal from the base A'J voltage is larger than the deviation of the standard 111: pressure gullet of the abnormal concentration signal, the concentration control is not performed. The control is as follows. That is, in the automatic copy density control method of the present invention, a failure in the control system is detected by comparing the one deviation described above, and the control is stopped when this failure is detected. It is possible to avoid excessive control of copy density due to

実施例 以下、添付図面を参照しつつ本発明の好ましい実施例に
よる複写機の複写濃度自動制御方法について説明する。EXAMPLE A method for automatically controlling copy density of a copying machine according to a preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

第１図は、本発明の第１の実施例による複写濃度自動制
御方法を実施するための装置を組み込んだ複写機の概略
を示す概略図である。FIG. 1 is a schematic diagram showing the outline of a copying machine incorporating a device for carrying out an automatic copy density control method according to a first embodiment of the present invention.

この第１図において、和号１は複写機を示し、この複写
機１は、通常の複写機と同様、感光ドラム２％露光ラン
グ３、トナー供給モータ４と現像バイアス’ＦａＪｆｉ
５とを備えた現像器６、チャージコロトロン７およびク
リーニング装ｆＭ８を有している。一方、符号１ｏは、
複写濃度自動制御装置を示し、この制御装置１ｏは、露
光ランプ３がら感光ドラム２に至る光路内にソレノイド
駆動により挿入される露光減衰板１１を備えている。こ
の露光減衰板１１は、ｊ−光ランプ３からの光の光路を
所定量減じるものである。感光ドラム２０周りには、こ
のドラム幅にわたり蝮数個の発光ダイオードを７列に配
してなる残留電荷消去ランプ１２が配置されている。上
記現像装置４より下流１１ｉ１１であってクリーニング
Ｍｆｊ１ｓの上流イ則の感光ドラム２０周辺には、複写
濃度読取りセンサ１３が設けられている。このセンサ１
３は、感光ドラム２上のトナー像の濃度を検出し、その
〃１ン度４８号Ｓを＋ｉ＋カするものである。In FIG. 1, Japanese number 1 indicates a copying machine, and this copying machine 1, like a normal copying machine, has a photosensitive drum 2% exposure rung 3, a toner supply motor 4, and a developing bias 'FaJfi'.
5, a charge corotron 7, and a cleaning device fM8. On the other hand, the code 1o is
This control device 1o is equipped with an exposure attenuation plate 11 inserted into the optical path from the exposure lamp 3 to the photosensitive drum 2 by driving a solenoid. This exposure attenuation plate 11 reduces the optical path of the light from the J-light lamp 3 by a predetermined amount. A residual charge erasing lamp 12 is arranged around the photosensitive drum 20, and is made up of seven rows of several light emitting diodes arranged over the width of the drum. A copy density reading sensor 13 is provided around the photosensitive drum 20 downstream 11i11 of the developing device 4 and upstream of the cleaning Mfj1s. This sensor 1
3 detects the density of the toner image on the photosensitive drum 2 and adds +i+ to the density of the toner image No. 48 S.

上ｉｉ３−ｋ　ｙ　ｔ　１３　ｔ７）　出力Ｍは、ｒＭ
　：ＶＩ　ｍ　ｅａ　器１４　ｃｖ一方の入力端に接続
されており、この演若増幅器１４の他方の入力端には、
第１基学・η１．圧発生器１５が接続されている。この
第１基ｉＬ　’ｌゎ、圧発生器１５は、露光減衰板１１
により減戟された光により露光されてできた感光ドラノ
・２上のｉ：；ｔ　像をトナー現像して形成されたトナ
ー像の理想の度を示ず基準ｗ５圧εｒｅ／　を発生する
ようＫなっている。上記演算増幅器１４０出力芹４　Ｋ
は、制御回路１６が接続されており、この制御回路１６
の出力端は、トナー供給モータ４を駆動するモータ駆動
回路１７および現像バイアス電極５のためのバイアス電
圧発生器１８に接続されている。Above ii3-k y t 13 t7) Output M is rM
:VI m ea circuit 14 cv is connected to one input terminal, and the other input terminal of this differential amplifier 14 is connected to
1st basic science・η1. A pressure generator 15 is connected. This first base iL'lゎ, the pressure generator 15 is connected to the exposure attenuation plate 11.
The i:;t image on the photosensitive drum 2, which was exposed to light attenuated by It has become. The above operational amplifier 140 output Seri 4K
is connected to the control circuit 16, and this control circuit 16
The output end of is connected to a motor drive circuit 17 for driving the toner supply motor 4 and a bias voltage generator 18 for the development bias electrode 5.

次に以上説明した構造の複写濃度自動制御装置ＩＯを参
照しつつ本発明の詳細な説明する。Next, the present invention will be described in detail with reference to the copy density automatic control device IO having the structure described above.

まず、トナーの感光ドラム２への試行付着を行なうが、
この試行付着の際は、鮪光ラング３からドラム２に至る
光路内に、ソレノイド駆動により鱈光減衰板１１を一時
的に挿入し、ドラム２上に一様に一定幅の残留電荷を作
り、次いで外留電荷消去ランプ１２のその複数個の発光
ダイオードの点灯の位置および時期を制（１１シて、ド
ラムｚ上に一定の小面積、例えば左ａ×７ｃｍの四角形
部分である試行付着のための電荷残留域を形成する。次
いで、この電荷残留域に通常の操作でトナーを付着し、
その濃度を上記濃度読、取りセンサ１３によって読み取
り、濃度信号Ｓを得る。演η増幅器１４は、この濃度信
号Ｓを基準１１１．圧Ｅｒｅ／　と比較し、その差に基
づいた差・偏゛りＳｌを出力する制御回路１６は、この
差信号Ｓ１を受け、この差信号Ｓ１に基づきモータ駆動
回路１７および）々イアスミ圧発生器１Ｂを制御して、
複写濃度を望まし〜・状態に近付ける。First, a trial adhesion of toner to the photosensitive drum 2 is performed.
During this trial attachment, a cod light attenuation plate 11 is temporarily inserted in the optical path from the tuna light rung 3 to the drum 2 by driving a solenoid, and a residual charge of a constant width is created uniformly on the drum 2. Next, control the lighting position and timing of the plurality of light emitting diodes of the external charge erasing lamp 12 (11). A charge residual area is formed.Next, toner is applied to this charge residual area by a normal operation,
The concentration is read by the concentration reading sensor 13, and a concentration signal S is obtained. The amplifier 14 uses this concentration signal S as a reference 111. A control circuit 16 receives this difference signal S1 and outputs a difference/deviation Sl based on the difference between the motor drive circuit 17 and the IASMI pressure generator based on this difference signal S1. Control 1B,
Bring the copy density closer to the desired condition.

以上の操作により初耳濃度を望ましい状テ、酢に制御す
ることができるが、上記したように例え（イ露光減衰板
１１の駆動用ソレノイドやセンサ１３の故障により、演
舞増幅器１４が複写濃陣が薄すぎであることを示す差信
号Ｓ１を出力してしまうことがある。そこで、本発明に
おいては、このような場合に、制御系、例えば制御回路
１６の作動を停止させるようにしている。このような作
動を行なうため、センサ１３の出力端に央に、比較器３
１の一方の入力端を接続し、かつこの比較器３１の他方
の入力端には、複写θ度異常を示す上記基準電圧εｒ＠
／　より所定値高い第２基準電圧）、圧Ｅｔｒｏ　を発
生する第一基準電圧発生器３２が接続されている。比較
器３１は、上記濃度信号Ｅを上記第２基準電圧Ｅｔｒｏ
　と比較し、この＃度イ６号Ｅが第２基準電圧Ｅｔｒｏ
　より大きいとき異常濃度（Ｎ号Ｓ２を出力する。この
異常濃度信号Ｓ２は、間接的に制御系の故障を示すもの
であり、制御回路１６は、比較器３１からこの異常濃度
信号Ｓ２を受けたとき、上記演算増幅器１４かもの差信
号ＳＩＫ基づく複写濃度制御を行なわないよ５ＩＣする
。かくして、本方嫌によれば制御系が故障の場合に複写
濃度が異常な状態とならない。Through the above operations, the initial density can be controlled to a desired level, but as described above (a), due to a failure in the driving solenoid of the exposure attenuation plate 11 or the sensor 13, the performance amplifier 14 is A difference signal S1 indicating that the thickness is too thin may be output. Therefore, in the present invention, in such a case, the operation of the control system, for example, the control circuit 16 is stopped. In order to perform such an operation, a comparator 3 is installed at the center of the output terminal of the sensor 13.
One input terminal of the comparator 31 is connected to the other input terminal of the comparator 31, and the reference voltage εr@ which indicates the copying θ degree abnormality is connected to
A first reference voltage generator 32 is connected which generates a pressure Etro (a second reference voltage higher than Etro by a predetermined value). The comparator 31 converts the concentration signal E into the second reference voltage Etro.
In comparison, this #degree A6 E is the second reference voltage Etro
When the value is greater than 1, the abnormal concentration signal S2 is output. This abnormal concentration signal S2 indirectly indicates a failure in the control system, and the control circuit 16 receives this abnormal concentration signal S2 from the comparator 31. At this time, the operational amplifier 14 does not perform the copy density control based on the difference signal SIK.Thus, according to the present invention, the copy density will not become abnormal even if the control system fails.

第２図および第３図は、第１図装置の実施に適用する場
合の濃度読取りセンサ１３から制御回路１６に至る信号
処理回路の詳細を示す図であり、濃度読取りセンサ１４
の出力は、前置増幅器１９、信号減衰器２０を経て差動
増幅器２１に入力され、その出力は、比較器２２を経て
増幅器２１にフィードバックされ、更にも１つのフィー
ド／ザットルーグにおける自動電圧ＩＡ整器２３により
自動電圧１１１ｓも行なう。こり差動増幅器２１の出力
をローパスフィルタ２４を通し第１図に示した演η増幅
器１４に導びき、ここで第７基準電圧Ｅｒａ／　との比
較を行ない、センサ１３で読み取った濃度信号Ｓがドラ
ム２の感光性に対して濃すぎるか、適正か、薄すぎるか
を示す差信号Ｓ１を出力し、ｆｌｌｌＢＭ１回路１６に
指令する。ここで、制御回路１６と演算増幅器１４の間
にもフイードノマツクループカ１設けられており、この
指令そのものの値を適確イヒするため制御回路１６で数
／θ回サすグ１ノングを行ない、第３図（イ）に示すよ
うにセンサ１３の腎ｔ、取り出力が本来的に非常にばら
つきが太き〜・こと力・ら生ずる誤り検出が多い判断結
果を多πに決瞼埋をもって確度の高い指令を制御回路１
６に与えるようにしている。以上のような回路構成にお
Ｘ、１て、（Ｓずれかの素子に故障が生じたことを、比
較＠＋　３１によって間接的に検知し、この検知の際に
制御回路１６を停止させ、複写濃度制御の全体を停ｊト
させるようにしている。第３図（ロ）、（ハ）＆１、そ
ｈそれ四−パスフィルタ２４の出力信号波形、サンプリ
ングの模様を示した図である。2 and 3 are diagrams showing details of the signal processing circuit from the concentration reading sensor 13 to the control circuit 16 when applied to the implementation of the apparatus shown in FIG.
The output of Automatic voltage 111s is also performed by the device 23. The output of the differential amplifier 21 is led through the low-pass filter 24 to the amplifier 14 shown in FIG. 1, where it is compared with the seventh reference voltage Era/, and the concentration signal S read by the sensor 13 is A difference signal S1 indicating whether the photosensitivity of the drum 2 is too dark, appropriate, or too thin is outputted and commanded to the fullBM1 circuit 16. Here, a feed control looper 1 is also provided between the control circuit 16 and the operational amplifier 14, and in order to accurately set the value of this command itself, the control circuit 16 inputs a signal that is input several times/θ times. As shown in Fig. 3 (a), the output of the sensor 13 is inherently highly variable, and the judgment results that result in many false detections are determined in a multiplicity of ways. Control circuit 1 provides highly accurate commands
I try to give it to 6. In the circuit configuration as described above, X, 1, it is possible to indirectly detect that a failure has occurred in one of the elements (S) by comparison @+ 31, stop the control circuit 16 at the time of this detection, The entire copying density control is stopped.FIGS. 3(b), 3(c) &1, and 3 are diagrams showing the output signal waveform of the four-pass filter 24 and the sampling pattern.

なお、濃度読取りセンサ１３の故障によりＩＩＵって１
濃度濃すぎ”の指令が出ることも考えら第１るＯこのた
め、更に″濃度濃すぎ”を検知するためσ〕比較器を設
け、この出力により制御ｌ硬１路１６の停止制御を行な
うこともできる。In addition, due to a failure of the concentration reading sensor 13, IIU is 1.
First, it is possible that a command for "concentration is too high" may be issued.For this reason, a comparator is provided to further detect "concentration too high", and the output of this comparator is used to control the stop of controll hard path 16. You can also do that.

発明の詳細 な説明したように、本発明によれば制御系が正常に作動
している間は適正濃度となるように濃度制御を行ない、
一方制御系の故障時にはこれを検出して制御を停止する
ようにしたので、制御系のの故障の影響を受けることが
ない。As described in detail, according to the present invention, while the control system is operating normally, the concentration is controlled so that the concentration is at an appropriate level,
On the other hand, in the event of a failure in the control system, this is detected and the control is stopped, so the system is not affected by a failure in the control system.

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

第１図は１本発明方法を実施するための装置の概略を示
す概略図、 第一図は、第１図の装置における濃度読取りセンサから
制御回路に至る信号処理回路の詳細を示す図、 酊３図は、第２図の回路の各部における波形図である。 １・・・・・・橡写機、１０・・・・・・複写節度制御
装置、１工・・・・・・霧光減衰板、１２・・・・・・
残留電荷消去ランプ、１３・・・・・・濃度読取りセン
サ、１４・・・・・・演算増幅器、１６・・・・・・制
御回路、３１・・・・・・比手続補正書 特許庁長官　若　杉　和　夫　殿 ■、小事件表示　昭和５８年特許願第２０５　（１２７
号２、発明の名称　複写機の複写濃度自動制御方法３、
補正をする者 事件との関係　出暉人 名　称　（５４９）富士セロツクス株式会社４、代理人 特許請求の範囲 複写機の複写操作の前に一時的に１）４光ランプからの
光の光量を所定量減じ、この光により感光ドラム上に一
定の小面積の帯電部を残し、この帯電部にトナーを試行
付着させ、この付着濃度を感光ドラム円面に配置した濃
度読取りセン日ノで読み取り濃度信号を得、この濃度信
号を予め定めた基ｐｉ、１″濃度に基づく基枠；電ＩＩ
：き演算増幅器により比較し、その出力によって現像バ
イアス電圧およびトナー供給量を制御する複写機の複写
濃度自動制御方法において、前記濃度信号を、１１１Ｊ
記基準電圧から所定値ずれた異常濃度信号と比較器で比
較し、１）ｒｊ記濃度信号の前記基準電圧からの偏差が
、ｎｆＪ　Ｗ己’Ｊ％常濃度信号の前記基準電圧からの
偏差より人きいとき、前記濃度制御を行なわないように
する。ことを特徴とする視ｌ写１幾の複写濃度自：１リ
ノ制御塑丑、。1 is a schematic diagram showing an outline of an apparatus for carrying out the method of the present invention; FIG. 1 is a diagram showing details of a signal processing circuit from a concentration reading sensor to a control circuit in the apparatus of FIG. 1; FIG. 3 is a waveform diagram at each part of the circuit of FIG. 2. 1... Copying machine, 10... Copying moderation control device, 1 piece... Fog light attenuation plate, 12...
Residual charge erasing lamp, 13... Concentration reading sensor, 14... Operational amplifier, 16... Control circuit, 31... Ratio procedural amendment Commissioner of the Patent Office Mr. Kazuo Wakasugi■, small case indication 1982 patent application No. 205 (127
No. 2, Title of the invention Automatic copy density control method for a copying machine 3,
Relationship to the case of the person making the amendment Name of the person (549) Fuji Serotox Co., Ltd. 4, Agent Claims: 1) Temporarily adjust the amount of light from a four-light lamp before copying with a copying machine. This light leaves a fixed small area of charged area on the photosensitive drum, toner is trial-adhered to this charged area, and the density of this adhesion is read by a density reading sensor placed on the photosensitive drum's circular surface and a density signal is obtained. and convert this density signal into a base frame based on a predetermined base pi, 1″ density;
: In an automatic copy density control method for a copying machine in which the density signal is compared by an operational amplifier and the developing bias voltage and toner supply amount are controlled based on the output thereof, the density signal is
A comparator compares it with an abnormal concentration signal that deviates from the reference voltage by a predetermined value. When there are many people, the density control is not performed. It is characterized by the fact that the copy density of the image is 1: 1 Reno control plastic.

Claims (1)

【特許請求の範囲】[Claims] 複写機の複写操作の前に一時的に露光ラングからの光の
光量を所定量減じ、この光により感光ドラム上に一定の
小面積の帯電部を残し、この帯電部にトナーを試行（＝
ｊ着させ、この付着濃度を感光ドラム周面に配置した濃
度読取りセンサで読み取り濃度信号を得、この濃度信号
を予め定めた基準濃度忙基づく基ｆＩＡ電、圧と演算増
幅器により比較し、その出力によって現像バイアス市、
圧およびトナー供給量を制御する複写４’ｔ！ｚの複写
濃度自！ｌｉＪ＋制御方法において、前記濃度信号を、
前記基準電圧から所定値ずれた異常濃度信号と比較器で
比Φνし、前記濃度信号の前ｉ１シ基ＣｖＩ電圧からの
偏差が、前記異常濃度信号の前記基準電圧からの偏差よ
り大きいとき、前記濃度制御を行なわないようにするこ
とを性徴とする複写機の複写濃度自動制御装置。Before the copying operation of the copying machine, the amount of light from the exposure rung is temporarily reduced by a predetermined amount, and this light leaves a charged area of a certain small area on the photosensitive drum, and the toner is applied to this charged area (=
This adhesion density is read by a density reading sensor placed on the circumferential surface of the photosensitive drum to obtain a density signal, and this density signal is compared with a predetermined standard fIA voltage and voltage based on a predetermined reference density value using an operational amplifier. Developed by Bias City,
Copy 4't to control pressure and toner supply amount! The copy density of z! In the liJ+ control method, the concentration signal is
A comparator compares the abnormal concentration signal with a predetermined value deviation from the reference voltage, and when the deviation of the concentration signal from the previous CvI voltage is larger than the deviation of the abnormal concentration signal from the reference voltage, the An automatic copy density control device for a copying machine whose characteristic is not to perform density control.
JP58205027A 1983-11-01 1983-11-01 Automatic control method of copy density in copying machine Pending JPS6097368A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP58205027A JPS6097368A (en) 1983-11-01 1983-11-01 Automatic control method of copy density in copying machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP58205027A JPS6097368A (en) 1983-11-01 1983-11-01 Automatic control method of copy density in copying machine

Publications (1)

Publication Number Publication Date
JPS6097368A true JPS6097368A (en) 1985-05-31

Family

ID=16500227

Family Applications (1)

Application Number Title Priority Date Filing Date
JP58205027A Pending JPS6097368A (en) 1983-11-01 1983-11-01 Automatic control method of copy density in copying machine

Country Status (1)

Country Link
JP (1) JPS6097368A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7769309B2 (en) 2006-10-18 2010-08-03 Sharp Kabushiki Kaisha Image forming apparatus and method with process control for stably forming images
JP2014119728A (en) * 2012-12-19 2014-06-30 Canon Inc Image forming apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7769309B2 (en) 2006-10-18 2010-08-03 Sharp Kabushiki Kaisha Image forming apparatus and method with process control for stably forming images
JP2014119728A (en) * 2012-12-19 2014-06-30 Canon Inc Image forming apparatus

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