JPH0353631B2 - - Google Patents
Info
- Publication number
- JPH0353631B2 JPH0353631B2 JP55065253A JP6525380A JPH0353631B2 JP H0353631 B2 JPH0353631 B2 JP H0353631B2 JP 55065253 A JP55065253 A JP 55065253A JP 6525380 A JP6525380 A JP 6525380A JP H0353631 B2 JPH0353631 B2 JP H0353631B2
- Authority
- JP
- Japan
- Prior art keywords
- reference target
- photoreceptor
- image
- density
- filter
- 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.)
- Expired - Lifetime
Links
- 108091008695 photoreceptors Proteins 0.000 claims description 20
- 230000003287 optical effect Effects 0.000 claims description 13
- 238000001514 detection method Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000001678 irradiating effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
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
- G03G15/04—Apparatus for electrographic processes using a charge pattern for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material
-
- 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
- G03G15/04—Apparatus for electrographic processes using a charge pattern for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material
- G03G15/043—Apparatus for electrographic processes using a charge pattern for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material with means for controlling illumination or exposure
- G03G15/0435—Apparatus for electrographic processes using a charge pattern for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material with means for controlling illumination or exposure by introducing an optical element in the optical path, e.g. a filter
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Exposure Or Original Feeding In Electrophotography (AREA)
- Control Or Security For Electrophotography (AREA)
Description
【発明の詳細な説明】
本発明は予め基準ターゲツトを感光体上に感光
した後これを現像して、そのトナー像の濃度を検
出し、得られた検出信号により複写濃度や白地濃
度がある規定値の範囲に納まるようトナー供給装
置、現像バイアス電圧、帯電器及び露光系などを
予め設定したモードに従つて総合的に制御するよ
うにした電子複写機の制御装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention involves exposing a reference target on a photoreceptor in advance, developing it, detecting the density of the toner image, and determining the copy density and white background density based on the obtained detection signal. The present invention relates to a control device for an electronic copying machine that comprehensively controls a toner supply device, developing bias voltage, charger, exposure system, etc. according to a preset mode so that the values fall within a range of values.
従来この種の複写機には、得られる複写の画質
特に複写機の濃度を一定に維持するための装置と
して、トナーの供給量を自動的に制御する装置
や、現像バイアス電圧を制御する装置などが採用
されている。 Conventionally, this type of copying machine has a device that automatically controls the amount of toner supplied, a device that controls the developing bias voltage, etc. in order to maintain the image quality of the resulting copy, especially the density of the copying machine, at a constant level. has been adopted.
例えば、特開昭53−12336号公報では、原稿台
の一部に特定の情報を用意しておき、この情報に
基づいて得られた感光体上のトナー像を検出し、
このトナー像の濃度が一定になるようトナー供給
量を制御している。また、特開昭54−3540号公報
では、原稿台の一側にそれとほぼ等して長さのチ
エツクパターンを用意し、このチエツクパターン
を光源の輝度を順次変化させながら感光体に投影
した後潜像を形成し、この潜像によつて露光量を
制御している。 For example, in Japanese Patent Application Laid-Open No. 53-12336, specific information is prepared on a part of the document table, and the toner image on the photoreceptor obtained based on this information is detected.
The amount of toner supplied is controlled so that the density of this toner image is constant. In addition, in Japanese Patent Application Laid-open No. 54-3540, a check pattern of approximately the same length is prepared on one side of the document table, and this check pattern is projected onto a photoreceptor while sequentially changing the brightness of the light source. A latent image is formed, and the amount of exposure is controlled by this latent image.
これら、従来例ではいずれも制御対象が、トナ
ー供給量や露光量等単一のフアクターであるう
え、このようなフアクターの制御をするための検
出要素が単一の基準ターゲツトにすぎなかつた
り、光源の輝度を変化させるものにあつては、潜
像の電位変化率に変化が現われるまでチエツクパ
ターンを走査し続ける必要があることからチエツ
クパターンが長大であることを必要とするもので
あつた。 In all of these conventional examples, the control target is a single factor such as toner supply amount or exposure amount, and the detection element for controlling such a factor is only a single reference target, or the light source In the case where the brightness of the latent image is changed, the check pattern needs to be long because it is necessary to continue scanning the check pattern until a change appears in the rate of change in the potential of the latent image.
ところで、本出願人は先に、従来の制御装置の
欠点を改善する目的で、トナー供給装置や現像バ
イアス電圧、帯電器及び露光系などを総合的に制
御する複写機において、特に基準ターゲツトのト
ナー像より検出した画像濃度を予め設定した基準
値と比較判定して、その判定結果により現像器へ
のトナー供給量を制御すると共に、上記現像器の
現像電極へ印加されたバイアス電圧または帯電器
の帯電電流の少なくとも一方を、中央制御回路よ
り出力された所定の制御モードにより制御するよ
うにした電子複写機の制御装置を出願している
（特願昭54−34231号）。この制御装置によればよ
り安定した画質の複写が常時得られる。 By the way, in order to improve the shortcomings of conventional control devices, the present applicant has previously developed a copying machine that comprehensively controls the toner supply device, developing bias voltage, charger, exposure system, etc. The image density detected from the image is compared and judged with a preset reference value, and the amount of toner supplied to the developing device is controlled based on the judgment result, and the bias voltage applied to the developing electrode of the developing device or the charging device is controlled. An application has been filed for a control device for an electronic copying machine in which at least one of the charging currents is controlled according to a predetermined control mode output from a central control circuit (Japanese Patent Application No. 34231/1982). According to this control device, copies with more stable image quality can always be obtained.
以上述べた制御装置では基準ターゲツトの数が
多い程画質の改善度合が良くなり、基準ターゲツ
トが１個であると画質の改善度合があまり良くな
い。 In the control device described above, the greater the number of reference targets, the better the degree of improvement in image quality, and the degree of improvement in image quality is not so good if there is only one reference target.
例えば、画像部のトナー濃度と背景部のトナー
濃度とが高いようなものであれば高濃度画像部の
トラブルを解決することで高濃度背景部のトラブ
ルも同時に解決できる可能性はあるが、各々の程
度により確実というわけにはいかない。 For example, if the toner density in the image area and the toner density in the background area are high, it is possible that solving the problem in the high density image area will also solve the problem in the high density background area at the same time. It cannot be said with certainty depending on the degree of
まして、画像部のトナー濃度が低く、背景部の
トナー濃度が高い場合には低濃度画像部のトラブ
ルを解決しようとすれば高濃度背景部のトラブル
が更に悪化し、高濃度背景部のトラブルを解決し
ようとすれば低濃度画像部のトラブルが更に悪化
してしまうということが発生し画質改善には限度
があり画質の改善度合があまり良くない。 Furthermore, if the toner density in the image area is low and the toner density in the background area is high, attempting to solve the problem in the low density image area will only make the problem in the high density background area worse, making it difficult to solve the problem in the high density background area. If an attempt is made to solve the problem, the problem in the low-density image area will become even worse, and there is a limit to the improvement in image quality, and the degree of improvement in image quality is not very good.
ところが、基準ターゲツトの数が複数個あれ
ば、少なくとも独立に画像部と背景部とのトナー
濃度検出が可能となつて前記したトラブルが解決
され画質の改善度合が良くなる。 However, if there are a plurality of reference targets, it becomes possible to at least independently detect the toner densities of the image area and the background area, which solves the above-mentioned problems and improves the degree of improvement in image quality.
本発明は以上の事情に鑑みなされたものであ
り、その目的は基準ターゲツトによるトナー像の
濃度を検出して、トナー供給装置や現像バイアス
電圧、帯電器及び露光系などを総合的に制御する
複写機において、基準ターゲツトを照射して得ら
れた反射光の光路内にフイルターを出入れ自在と
することにより得られるようにした電子写真複写
機の制御装置を提供することにある。 The present invention was made in view of the above circumstances, and its purpose is to detect the density of a toner image based on a reference target and comprehensively control a toner supply device, developing bias voltage, charger, exposure system, etc. An object of the present invention is to provide a control device for an electrophotographic copying machine in which a filter can be moved in and out of the optical path of reflected light obtained by irradiating a reference target.
以下この発明の一実施例を図面を参照して詳述
する。第１図はこの発明の制御装置を採用した電
子複写機で、複写機本体１の上部に図示しない原
稿を載置するための原稿台２が設けられている。
原稿台２の下側には第１図に示すように基準ター
ゲツト３と、原稿台２に沿つて移動する露光ラン
プ４が設けられ、この電光ランプ４により原稿及
び基準ターゲツト３が露光できるようになつてい
る。原稿または基準ターゲツト３の反射光は反射
鏡５ａ，５ｂ，５ｃ，５ｄレンズ５ｅなどからな
る光学系５を経て複写機本体１内の感光体６へ達
し、帯電器２５により帯電された感光体６の周面
に静電潜像を形成する。感光体６の静電潜像は次
の現像器７によりトナー像に現像される。現像器
７は高圧電圧が印加された現像電極８を感光体６
の周面に沿つて有しており、トナー供給装置９よ
り供給されたトナーを含む現像剤により、上記感
光体６上の静電潜像を現像するもので、この現像
器７以降に設けた転写器１２とクリーニング機構
１１との間には感光体６上に形成された基準ター
ゲツト３のトナー像の濃度を検出する検出器１０
が設けられている。 An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an electronic copying machine employing the control device of the present invention, in which a copying machine main body 1 is provided with a document table 2 on top of which a document (not shown) is placed.
As shown in FIG. 1, a reference target 3 and an exposure lamp 4 that moves along the document table 2 are provided below the document table 2, and the electric lamp 4 is used to expose the document and the reference target 3. It's summery. The reflected light from the original or the reference target 3 reaches the photoreceptor 6 in the copying machine main body 1 through the optical system 5 consisting of reflecting mirrors 5a, 5b, 5c, 5d, and lenses 5e, and the photoreceptor 6 is charged by the charger 25. forms an electrostatic latent image on the peripheral surface of the The electrostatic latent image on the photoreceptor 6 is developed into a toner image by the next developing device 7. A developing device 7 connects a developing electrode 8 to which a high voltage is applied to a photoreceptor 6.
The electrostatic latent image on the photoconductor 6 is developed with a developer containing toner supplied from the toner supply device 9. A detector 10 is provided between the transfer device 12 and the cleaning mechanism 11 to detect the density of the toner image of the reference target 3 formed on the photoreceptor 6.
is provided.
検出器１０は例えば発光ダイオードなどの発光
素子１０ａ及びフオトダイオードなどの受光素子
１０ｂからなる反射型センサであつて、感光体６
上の有効複写面外に形成された基準ターゲツト３
のトナー像に対応するよう設けられており、この
トナー像の濃度から画像部の濃度及び背景部の濃
度が検出できるようになつている。 The detector 10 is a reflective sensor including a light emitting element 10a such as a light emitting diode and a light receiving element 10b such as a photodiode.
Reference target 3 formed outside the upper effective copy plane
The density of the image area and the density of the background area can be detected from the density of this toner image.
１３はフイルタであり、前記光学系５の光路
５′に出入り自在となるようにロータリソレノイ
ド１４の可動部１４ａに設けてある。 Reference numeral 13 denotes a filter, which is provided on the movable portion 14a of the rotary solenoid 14 so as to be able to move in and out of the optical path 5' of the optical system 5.
そして、前記検出器１０の検出信号は第３図に
示す如く増幅回路１５で適当なレベルの信号に増
幅された後に比較回路１６に送られて基準回路１
７より入力された基準濃度信号と比較され、その
結果が中央制御回路１８に入力される。 The detection signal from the detector 10 is amplified to an appropriate level signal by an amplifier circuit 15 as shown in FIG.
It is compared with the reference concentration signal inputted from 7, and the result is inputted to the central control circuit 18.
中央制御回路１８では上記比較回路１６より入
力された濃度判定結果に従つて制御モードを選択
し、出力回路１９を経て各種制御回路２０へ制御
信号を送るようにしてある。該制御回路２０とし
ては現像バイアス制御回路２０ａ、露光ランプ制
御回路２０ｂ、トナー供給量制御回路２０ｃ、帯
電電流制御回路２０ｄなどである。 The central control circuit 18 selects a control mode according to the density determination result input from the comparison circuit 16, and sends control signals to various control circuits 20 via an output circuit 19. The control circuits 20 include a developing bias control circuit 20a, an exposure lamp control circuit 20b, a toner supply amount control circuit 20c, and a charging current control circuit 20d.
しかして、基準ターゲツト３のトナー像より検
出した画像濃度を予め設定した基準濃度と比較判
定し、その判定結果に従つて現像バイアス電圧、
露光ランプ４の光量、現像器７へのトナー供給
量、帯電器２５の帯電電流などを制御するので、
現像剤や露光ランプなどが劣化した場合や湿度が
高くなつた場合でも複写機の濃度を一定に維持制
御してより安定した画質の複写が常時得られる。 Then, the image density detected from the toner image of the reference target 3 is compared and judged with a preset reference density, and the developing bias voltage is adjusted according to the judgment result.
Since the light intensity of the exposure lamp 4, the amount of toner supplied to the developing device 7, the charging current of the charger 25, etc. are controlled,
Even if the developer, exposure lamp, etc. deteriorate or the humidity increases, the density of the copying machine can be kept constant and copies with more stable image quality can be obtained at all times.
また、フイルタ１６の駆動手段であるロータリ
ーソレノイド１４を励磁、消磁動作してフイルタ
１３を光路５′に出入り動作すれば同一基準ター
ゲツト３の感光体６に投影される像の露光量が切
換り、そのトナー像の濃度を異ならせることがで
きて複数の基準ターゲツト３を設けたと同様にな
つて画質改善度合を良くできる。この場合、露光
ランプ４が第１図に示された位置においてフイル
タ１３を光路５′に挿入して基準ターゲツト３を
感光体６に投影させ原稿部のトナー像を形成し、
次いで原稿の走査が終了して走査系が元の位置に
戻る間にソレノイド１４を作動させてフイルタを
光路５′から脱出させて基準ターゲツト３を感光
体６に投影し、背景部のトナー像を形成する。こ
のように、フイルタの切り換えは瞬時に行われる
が、感光体を照射する光は安定した状態で減光さ
せられる。 Further, by energizing and demagnetizing the rotary solenoid 14, which is a driving means for the filter 16, and moving the filter 13 into and out of the optical path 5', the exposure amount of the image projected onto the photoreceptor 6 of the same reference target 3 is switched. Since the density of the toner image can be made different, the degree of improvement in image quality can be improved in the same manner as when a plurality of reference targets 3 are provided. In this case, the exposure lamp 4 is placed in the position shown in FIG. 1, the filter 13 is inserted into the optical path 5', the reference target 3 is projected onto the photoreceptor 6, and a toner image of the original is formed
Next, after scanning the original and while the scanning system returns to its original position, the solenoid 14 is operated to remove the filter from the optical path 5', projecting the reference target 3 onto the photoreceptor 6, and removing the toner image in the background. Form. In this way, the filters are switched instantaneously, but the light irradiating the photoreceptor is dimmed in a stable manner.
なお、フイルタ１３を複数設けていずれか１つ
が光路５′中に入るようにしても良いと共に、検
出器１０は現像器７と転写器１２との間に設けて
も良い。 Note that a plurality of filters 13 may be provided so that one of them enters the optical path 5', and the detector 10 may be provided between the developing device 7 and the transfer device 12.
以上詳述したように、本発明は１個の基準ター
ゲツトの光路中にフイルターを出入自在に配する
ことによつて、複数の基準ターゲツトを配置して
同時にそれらのトナー像等を作成し、それぞれ検
出して画質改善のための制御する場合と同じ効果
が得られるのであつて、フイルターは基準ターゲ
ツトから感光体に至るまでのいずれかのすでに存
在する空間を利用しえるから、基準ターゲツトの
設置部ひいては複写機の光学系、感光体等の設置
スペースを大きくすることなく複写画質をきめ細
かく改善するのに必要な制御データを得ることが
でき複写機内部の設置スペースと画質制御データ
の検出精度とを極めて高い次元で両立することが
できるという効果を有するものである。また、感
光体を照射する光量の切換えを極めて短時間内に
安定して行うことができ、走査系が基準ターゲツ
トを走査する時間を最小限とし、複写機の設置ス
ペース上有利になるという利点もある。 As described in detail above, the present invention arranges a filter in the optical path of one reference target so as to be able to move in and out, thereby arranging a plurality of reference targets and simultaneously creating toner images, etc. of each of them. The same effect as detection and control for image quality improvement can be obtained, and since the filter can utilize any existing space from the reference target to the photoreceptor, it is possible to In turn, it is possible to obtain the control data necessary to finely improve the quality of copied images without increasing the installation space for the optical system, photoreceptor, etc. of the copying machine. This has the effect of being able to coexist on an extremely high level. Another advantage is that the amount of light irradiating the photoreceptor can be switched stably within an extremely short period of time, minimizing the time it takes for the scanning system to scan the reference target, which is advantageous in terms of installation space for the copying machine. be.
図面は本発明の一実施例を示し、第１図は複写
機全体の構成図、第２図はフイルタの詳細説明
図、第３図は制御系のブロツク図である。
２は原稿置台、３は基準ターゲツト、６は感光
体、１３はフイルタ、５′は光路。
The drawings show one embodiment of the present invention; FIG. 1 is a block diagram of the entire copying machine, FIG. 2 is a detailed explanatory diagram of a filter, and FIG. 3 is a block diagram of a control system. Reference numeral 2 denotes an original table, 3 a reference target, 6 a photoreceptor, 13 a filter, and 5' an optical path.
Claims (1)
を感光体６に投影して前記基準ターゲツトの潜像
を形成し、この潜像を現像してトナー像を形成
し、得られたトナー像の濃度に応じて、画像形成
条件を制御するようにした電子複写機において、 前記基準ターゲツト３を照射した際の反射光が
感光体６に投影される光路５′中に出入自在に設
けられ、感光体６上の露光量を切換えるフイルタ
１３と、 該フイルタ１３を前記光路５′中に出し入れさ
せる駆動手段とを備え、 前記基準ターゲツト３に対する露光走査に応じ
て、前記駆動手段を制御し、感光体の有効複写面
外にフイルタを通した基準ターゲツトのトナー像
とフイルタを通さない基準ターゲツトのトナー像
とを形成することを特徴とする電子複写機の制御
装置。[Claims] 1. Reference target 3 placed near document table 2
is projected onto the photoreceptor 6 to form a latent image of the reference target, this latent image is developed to form a toner image, and image forming conditions are controlled according to the density of the obtained toner image. In the electronic copying machine, a filter 13 is provided so as to be able to enter and leave the optical path 5' through which the reflected light when the reference target 3 is irradiated is projected onto the photoreceptor 6, and which switches the amount of exposure on the photoreceptor 6; a driving means for moving the filter 13 in and out of the optical path 5'; the driving means is controlled in accordance with exposure scanning for the reference target 3, and the reference target passing through the filter is moved outside the effective copying surface of the photoreceptor; A control device for an electronic copying machine, characterized in that it forms a toner image and a toner image of a reference target that does not pass through a filter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6525380A JPS56161554A (en) | 1980-05-19 | 1980-05-19 | Control device for electronic copying machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6525380A JPS56161554A (en) | 1980-05-19 | 1980-05-19 | Control device for electronic copying machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56161554A JPS56161554A (en) | 1981-12-11 |
| JPH0353631B2 true JPH0353631B2 (en) | 1991-08-15 |
Family
ID=13281549
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6525380A Granted JPS56161554A (en) | 1980-05-19 | 1980-05-19 | Control device for electronic copying machine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56161554A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS592058A (en) * | 1982-06-28 | 1984-01-07 | Ricoh Co Ltd | Method for making patterned image for controlling image density in electrophotographic copying machine |
| JPS5951353U (en) * | 1982-09-28 | 1984-04-04 | コニカ株式会社 | recording device |
| JPS59149338A (en) * | 1983-02-15 | 1984-08-27 | Konishiroku Photo Ind Co Ltd | Detector for abnormality of exposure lamp in electrophotographic copying device |
| JPS59154468A (en) * | 1983-02-22 | 1984-09-03 | Konishiroku Photo Ind Co Ltd | Electrophotographic copying machine |
| JPS61213865A (en) * | 1985-03-18 | 1986-09-22 | ゼロツクス コーポレーシヨン | Automatic setter for electrophotographic printing machine |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5312336A (en) * | 1976-07-20 | 1978-02-03 | Sharp Corp | Device for supplying toner |
| JPS543540A (en) * | 1977-06-10 | 1979-01-11 | Canon Inc | Automatic exposure device |
-
1980
- 1980-05-19 JP JP6525380A patent/JPS56161554A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5312336A (en) * | 1976-07-20 | 1978-02-03 | Sharp Corp | Device for supplying toner |
| JPS543540A (en) * | 1977-06-10 | 1979-01-11 | Canon Inc | Automatic exposure device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56161554A (en) | 1981-12-11 |
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