JPS59107341A - Automatic adjusting device for unevenness of image density of electrostatic copying machine - Google Patents

Abstract

PURPOSE:To equalize a quantity of light distribution, and to prevent generation of unevenness of an image density by always monitoring an exposure quantity of light by use of a reference passive reflector and a quantity of light measuring photodetector, and adjusting automatically a passive reflector angle of a light source, when the quantity of light is varied. CONSTITUTION:A reference reflecter 10 is installed to both outsides of contact glass 1 of the lower face of an original platen, and a quantity of light measuring photodetector 11 is provided on a position which does not obstruct a luminous flux, just in front of a photosensitive body 8. A reflecter 3 for forming a parabola of a light source 4 is divided into two at a center point 3a, and the angle is adjusted by a motor 12. A part of a luminous flux of the light source 4 is reflected by the reflecter 10, the light quantity is always monitored by the photodetector 11, and as for its output, the quantities of light of the left and right are compared by a CPU13, and when there is a difference, the angle of the reflecter 3 is adjusted. Therefore, the quantity of light distribution in the width direction of the photosensitive body 8 always becomes uniform, and generation of unevenness of an image density can be prevented.

Description

【発明の詳細な説明】 技術分野 この発明は、静電複写機の画像濃度ムラ自動調整装置４
に関する。DETAILED DESCRIPTION OF THE INVENTION Technical Field This invention relates to an image density unevenness automatic adjustment device 4 for an electrostatic copying machine.
Regarding.

従来技術 ｌ￥ｒ＋電複写機の原稿露光照明光源としては、抛物面
等の反射板を有する棒状蛍光ランプが広く使用されてい
るが、この種のランプは経時的劣化により軸方向の発光
凝分布にムラを生ずる。又、コンタクトガラスの内面、
レンズ及びミラーにトナーや定着オイルなどが付着し、
経時的（二値光体に達する光量が部分的に変動し、画像
濃度ムラが発生する。Conventional technology L\r+ Rod-shaped fluorescent lamps with a reflective plate such as a mirror surface are widely used as the original exposure illumination light source for electronic copying machines, but this type of lamp deteriorates over time and has a tendency to change the luminous density distribution in the axial direction. Causes unevenness. Also, the inner surface of the contact glass,
Toner, fixing oil, etc. may adhere to the lenses and mirrors.
Over time (the amount of light reaching the binary light body varies partially, causing uneven image density.

従来、この画像濃度ムラの調整は、光源ランプの光路の
側に遮光板を調整可能に設け、ザービスマンがコピーの
画像濃度を見ながら遮光板の位１ｉを調整することによ
り行なっていたため、手数が摺るばかりでなく、画像濃
度ムラが発生する都度ザービスマンを１１゛Ｊζぶ必要
があり、コスト高につく欠点があった。Conventionally, this adjustment of image density unevenness was done by installing an adjustable light-shielding plate on the optical path side of the light source lamp and adjusting the position of the light-shielding plate while checking the image density of the copy, which was a time-consuming process. In addition to printing, it was necessary to use a serviceman of 11 Jζ each time uneven image density occurred, which resulted in high costs.

に１　　的 本光明シま、従来の画像濃度ムラ調整の上述の実情にか
んがみ、間車な構成で絶対光ｉｔ　ｆ動及び画像濃度ム
ラを常時検知し、その結果により自動的に光量調整を行
ない走査方向に直角方向の光ｂ↓分布を均一・にすると
ともに絶対的光咽をも自動的に調整することの出来る画
像濃度ムラ自動調整装置を提供することを目的とする。1. In view of the above-mentioned circumstances of conventional image density unevenness adjustment, our company uses a compact configuration to constantly detect absolute light movement and image density unevenness, and automatically adjusts the light intensity based on the results. It is an object of the present invention to provide an image density unevenness automatic adjustment device that can make the light b↓ distribution in the direction perpendicular to the scanning direction uniform and can also automatically adjust the absolute brightness.

構　　成 以Ｆ１本発町を図面に示す実施例にもと−）いて詳細に
説明する。The configuration of the F1 engine will be explained in detail based on the embodiment shown in the drawings.

第１図は本発明の画像濃度ムラ自動制御装Ｌｆ＋′を有
する静電複写機の露光装置及び感光体ドラム周辺の要ｉ
死を示す図である。FIG. 1 shows the main points around the exposure device and photoreceptor drum of an electrostatic copying machine having an image density unevenness automatic control system Lf+' of the present invention.
It is a diagram showing death.

原稿台ガラス１上に載置された原稿２は抛物面反射板６
を有する棒状蛍光ランプ４により照明され、その反射光
束はミラー５と結像レンズ６とより成る露光々学系７に
より感光体ドラム８上に定位置９で結像する。原稿台と
感光体ドラム８とが同期して移動することにより、（又
は原稿台が固定し、−部のミラーと光源ランプとが感光
体ドラムと同期して移動することにより）スリット露光
走査か行なわれる。こ〜、迄にのべた構成は従来の静電
複写機と竹に変るところはない。The original 2 placed on the original platen glass 1 is placed on the mirror surface reflection plate 6.
The reflected light beam is illuminated by a rod-shaped fluorescent lamp 4 having a mirror 5 and an imaging lens 6 to form an image on a photosensitive drum 8 at a fixed position 9. Slit exposure scanning is performed by moving the document table and the photoreceptor drum 8 in synchronization (or by fixing the document table and moving the negative mirror and the light source lamp in synchronization with the photoreceptor drum). It is done. The configuration described so far is the same as that of conventional electrostatic copying machines and bamboo.

しかし、この実施例の装）湿ではさらに、第１図及び第
２図に示す如く、原稿台の下面のコンタクトガラス１の
走査方向に関して両件側に基準濃度を有する基準反射板
１０が設けられている。光源ランプ４の照明範囲はこの
基準反射板１０に及んでおり、第６図に示す如く、その
反射光は結像レンズ乙により、図中破線で示す如く、原
稿画像の露光々束の外側を進むが、その光路には感光体
８の直前で原稿画像の露先々束を遮らない位置に光量測
定用受光素子１１が設けられている。したがって、基準
反射板１０による光源ランプ４の反射光はレンズ６によ
り両側の受光素子１１に投影され光）社が測定される。However, in the apparatus of this embodiment, as shown in FIGS. 1 and 2, reference reflection plates 10 having a reference density are provided on both sides of the contact glass 1 on the lower surface of the document table in the scanning direction. ing. The illumination range of the light source lamp 4 extends to this reference reflector 10, and as shown in FIG. 6, the reflected light is directed to the outside of the exposure beam of the original image by the imaging lens B, as shown by the broken line in the figure. On the optical path, a light-receiving element 11 for measuring the amount of light is provided at a position immediately in front of the photoreceptor 8 and at a position that does not block the bundle of exposed edges of the original image. Therefore, the light reflected from the light source lamp 4 by the reference reflector 10 is projected onto the light receiving elements 11 on both sides by the lens 6 and is measured.

又、第１図及び第４図に示す如く、光源ランプ４の反射
板６は長さ方向の中心点６ａで２つの部分に分割されて
おり、この点で僅かの角度で折り曲げることがｌ拝能と
なっている。反射板６はこの中心点３ａで固定されてお
り、両端３ｂ、３ｃは移動モータ１２によりランプ４と
の距離がある範囲内で調整ｕ１能となっている。Further, as shown in FIGS. 1 and 4, the reflector 6 of the light source lamp 4 is divided into two parts at a longitudinal center point 6a, and it is convenient to bend it at a slight angle at this point. It has become a Noh performance. The reflector 6 is fixed at the center point 3a, and both ends 3b and 3c can be adjusted by a moving motor 12 within a certain distance u1 from the lamp 4.

反射板６は軸に直角に切った断面が抛物線となっている
ので、第５１１２１　（ａ）に示す如く、反Ｑ４板６を
ランプ４に近イ」けた場合は、（ｂ）図に示す通常状態
に比して反射光束か原稿２を照らず範囲か拡かり、所定
のスリット幅の部分の照度は小さくなる。逆に（ｃ）図
に示す如く、反射板６がランプ４より連ざかった場合は
、反射光束が原稿２を照らすｉｊＱ囲か挟まり、照度が
高くなる。Since the cross section of the reflector plate 6 cut perpendicular to the axis is a parabolic line, when the anti-Q4 plate 6 is placed close to the lamp 4 as shown in Figure 51121 (a), the normal shape shown in Figure (b) Compared to the state, the reflected light beam does not illuminate the original 2, and the range is expanded, and the illuminance of the portion with the predetermined slit width becomes smaller. On the other hand, as shown in Figure (c), if the reflector 6 is connected to the lamp 4, the reflected light beam will be caught between the ijQ frames that illuminate the original 2, and the illuminance will be high.

１−記の移動モータ１２は前記の各九駁測定用受光素丁
・１１による検フ４１信号により、’ＣＰＵ１３を介し
て制１ＩＩｌｌされるようになっている。The moving motor 12 (1-) is controlled via the CPU 13 by the detection signal 41 from each of the nine measurement light receiving elements 11.

この装置６′は以」―の如く構成されているので、原稿
露光走査時、照明光＃、４の光束の−ｆｉ１１　’ｔま
２つの基準反射板１０に当り、露光々学系７を介して光
量測定用受光素子１１」二に投影され光計が検知され、
夫々の出力信号がＣＰＵ１５に入力され、互いに比較さ
れる。もし、２つの出力信号の差かある値以」二の場合
は移動モータ１２のいずれか一方か選択駆動され反射板
６の光源４に対する位置を片側たけ変化させ、２つの光
量測定用受光素子１１の信号の差か所定の値以下になれ
ば停止する。その結果、走査方向に直角方向の画像濃度
ムラは補正される。This device 6' is constructed as follows, so that during exposure scanning of the original, the illumination light beam #4 hits the two reference reflectors 10 and passes through the exposure optical system 7. The light is projected onto the light receiving element 11'2 for measuring the amount of light and is detected by the light meter.
The respective output signals are input to the CPU 15 and compared with each other. If the difference between the two output signals is more than a certain value, one of the moving motors 12 is selectively driven to change the position of the reflecting plate 6 relative to the light source 4 by one side, and the two light receiving elements 11 for measuring the amount of light are moved. If the difference between the signals becomes less than a predetermined value, it will stop. As a result, image density unevenness in the direction perpendicular to the scanning direction is corrected.

ランプ反射板ろを第６図に示す如く長手方向に６分割し
、夫々の接続部３ｄ、３ｅで屈曲可能とし、移動モータ
１２を両端ｒｌＦのほか中央部にも設け、２つの光量１
１１１１　常用受光素子１１からの信号をＣＰＵ１３に
おいて、互いに比較し、かつ基準値とも比較するように
して、両者が共に基準値より低い場合は全部の駆動モー
タ１２を駆動して原稿照射照度を上げる方向に反射板６
を全体的に移動させるとともに両側の移動モータの移動
量を変えること（−よりムラを補正するようにすれば、
走査方向と直角方向の光量分布を均一にするとともに、
絶対的光れ十をも自動的に調整することができる。As shown in FIG. 6, the lamp reflector plate filter is divided into six parts in the longitudinal direction, and can be bent at the respective connecting parts 3d and 3e.Movement motors 12 are provided at both ends rlF as well as in the center part, and the two light intensities 1
1111 The CPU 13 compares the signals from the regular light receiving element 11 with each other and with a reference value, and if both are lower than the reference value, drives all drive motors 12 to increase the illumination intensity of the original. reflector plate 6
By moving the whole area and changing the amount of movement of the movement motors on both sides (- to correct the unevenness more,
In addition to making the light intensity distribution uniform in the direction perpendicular to the scanning direction,
Absolute light intensity can also be adjusted automatically.

光量低下や照度ムラは経時的に起るものであるから、上
記の光：１：検知及び調整は１枚コピーする毎に行なう
必要はなく、例えば１０枚コピーする度に１回程度の割
合で行なえばよい。１回の検知動作はコピーの１枚の画
像形成に同期して行ない、２〜６枚のコピーの間に調整
が完了するように設定するのがよい。Since light intensity reduction and illuminance unevenness occur over time, it is not necessary to perform the above light detection and adjustment every time one copy is made, for example, once every 10 copies. Just do it. It is preferable to perform one detection operation in synchronization with the image formation of one copy, and set the adjustment so that it is completed between 2 and 6 copies.

効　　果 以上の如く、本発明によれば、走査方向と直角方向の光
量ムラは常に一定の範囲内に納まるように自動調整され
、さらに光（１ｉの絶対値も基姑植よりずれないように
自５ν〕調整することか出来、調整に人手をわずられず
ことが避けられ、常に良好なコピーを得ることができる
。Effects As described above, according to the present invention, the unevenness in the amount of light in the direction perpendicular to the scanning direction is automatically adjusted so that it always falls within a certain range, and furthermore, the absolute value of the light (1i) is adjusted so that it does not deviate from the basic value. 5ν] It is possible to make adjustments, avoid the need for manual adjustment, and always obtain good copies.

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

第１図は本発明を適用した静電複写機の露光装置の断面
図、第２図はその原稿台の上面図、Ｍ　３図はその光路
を図式的に示す図、第４図はその光源ランプ及び反射板
を詳細に示す平面図、第５図（ａ）　（ｂ）（ｃ）は光
源と反射板との相対位置の変化による原稿照度の変化を
説明する図式図、第６図はランプの反射板の他の実施例
を示す平面図である。 １・・・原稿台カラス　　２・・・原稿３・・・光源反
射板　　　４・・・棒状光源８・・・感光体ドラム　　
１０・・・基準反射板１１・・・光敏検知手段　１２・
・・反射板移動モータ１６・・・制御手段（ＣＰＵ） 代理人　弁理士　　伊　藤　武　久　　、９Ｈ５′、　
　＋　　Ｈ−・（ ｚ６支　２　、： ０ 第３１Ａ 第４１１）Fig. 1 is a sectional view of the exposure device of an electrostatic copying machine to which the present invention is applied, Fig. 2 is a top view of the document table, Fig. M3 is a diagram schematically showing its optical path, and Fig. 4 is its light source. A plan view showing the lamp and the reflector in detail, Figures 5(a), (b), and (c) are schematic diagrams illustrating changes in document illuminance due to changes in the relative position between the light source and the reflector, and Figure 6 shows the lamp. FIG. 3 is a plan view showing another example of the reflector of FIG. 1... Original table crow 2... Original 3... Light source reflection plate 4... Rod-shaped light source 8... Photosensitive drum
10...Reference reflecting plate 11...Light sensitivity detection means 12.
...Reflector moving motor 16...Control means (CPU) Agent: Patent attorney Takehisa Ito, 9H5'
+ H-・(z6 branch 2,: 0 31st A 411th)

Claims (1)

【特許請求の範囲】[Claims] （１）　　原稿台カラス上に載１質した原稿を感光体ド
ラムと゛ト行に設けられた反則板（＝Ｊき棒状光源によ
り１１α明し、ドラムの軸方向と直角方向に走査してス
リット露光を行なう静電俵写機の走査方向に１０角方向
の画Ｉｗ　Ｄ度ムラ自！Ｉ’ｏ）ｒｉ：ｉ整ｋ　ｌ！’
ｆにおいて、」−記俸状光源の軸方向に２つ以」一般け
られた基準反射板と、各基準反射板による光源の光の反
射光が露先々学系により投影される位１６に夫々設けら
れた光ｈ；倹知知手段、光＋ＪＪ＋！に対する反射板の
位【；・シを部分的に変化させる駆動手段と、前記の各
光量検知手段の検知信号により」二記の反射板駆動手段
を制御する手段とを有することを１“、ｊ徴とする画像
濃度ムラ自動調整装ｆｔｆ　０（２）　　上記の基準反
射板が」二記の原稿台ガラスの原稿走査方向に関し両件
側の下面に設けられ、上記の光重７演知手段が感光体直
前の原稿画像光束の両件側（二設けられていることを特
徴とする特ＩＮＦ調求の範囲第１項に記載の画像濃度ム
ラ自動調整装置。(1) The original placed on the original platen glass is illuminated by 11α by a light source installed in the row with the photoreceptor drum. The image in the 10 angle direction in the scanning direction of the electrostatic bale camera is uneven! '
At f, two or more reference reflectors are generally provided in the axial direction of the diagonal light source, and the light reflected from the light source by each reference reflector is projected by the aperture optical system, respectively. Provided light h; wisdom means, light + JJ +! 1", j Image density unevenness automatic adjustment device ftf 0 (2) The above-mentioned reference reflector is provided on the lower surface of both sides of the original table glass in the original scanning direction, and the above-mentioned light weight 7 indicating means is provided. The image density unevenness automatic adjustment device according to item 1 of the scope of special INF investigation, characterized in that two devices are provided on both sides of the document image light beam immediately before the photoreceptor.