JPS60138534A - Lighting device of copying machine - Google Patents

Abstract

PURPOSE:To save the electric power when a small-sized original is copied and increase the copying speed by providing the lighting device of a copying machine which has plural light sources with at least two light source groups which are turned on selectively according to copy size. CONSTITUTION:The light source consist of two light source groups composed of the same eight spot type electric bulbs. Namely, the 1st light source group of l1-l8 is turned on to light an original A3, and the 2nd light source group of l1'-l8' is turned on to light an original of A5. Both light source groups are arrayed on the same line and connected into a parallel circuit. In this case, electric bulbs in each light source group are arrayed at narrower intervals toward an end part in consideration of the square rule. Turning-on circuits are changed over by using switches. Thus, the power consumption when a small- sized original is copied is saved by the simple constitution and the copying speed is increased.

Description

【発明の詳細な説明】 技術分野 本発明は、複数個の光源を有する複写機の原稿照明装置
に関する。TECHNICAL FIELD The present invention relates to a document illumination device for a copying machine having a plurality of light sources.

従来技術 従来の複写機の照明は、原稿の大小に関係なく常に最大
原稿幅に合わせて行なっている０即ち、第１図に示すよ
うに原稿台上に各サイズの原稿をセンター基準で縦直き
にした場合、例えばＡ５（縦４２ｏｍｍ）を最大原稿と
すると照明幅は４２０覇であるが、”Ａ４（縦２９７ｆ
ｆｉ＋Ｉ＋）、Ａ５（縦２１０諭）等の小サイズの原稿
を複写する場合にも、上記のＡろに対する照明幅を採用
している。これは、最近複写高速化に伴い原稿を鞭置き
にする傾向があり、従って管状光源が幅広化となってい
ることを考慮し、またハガキ、名刺等の極小サイズの複
写が望まれていることをも考え合わせると非合理的であ
り、特に小さな原稿の場合に不必要な場所を照明するこ
とであり、電力のむだづかいは免れない。Prior Art The illumination of conventional copying machines is always adjusted to the maximum width of the original, regardless of the size of the original. In other words, as shown in Figure 1, originals of various sizes are placed vertically on the original table with the center referenced. For example, if the maximum document is A5 (vertical 42mm), the illumination width will be 420mm, but if "A4 (vertical 297mm)" is
Even when copying small-sized originals, such as A5 (210 in.) or A5 (vertical 210 in.), the above illumination width for A-ro is adopted. This is due to the fact that there is a tendency to use a whip rest for originals as copying speeds have increased recently, and tubular light sources have become wider as a result, and there is also a desire for extremely small size copies of postcards, business cards, etc. Taking this into account, it is irrational, and especially in the case of small manuscripts, unnecessary areas are illuminated, which inevitably results in wasted power.

上記の難点を除くためにいくつかの解決法が開示されて
いるが、そのうち複数の点光源を用いた例を次に挙ける
。Several solutions have been disclosed to eliminate the above-mentioned difficulties, and an example using a plurality of point light sources will be listed below.

まず、従来より公知のスリット走査式照明装置の構成を
簡単に述べておく。第２図に示すように、核数個の点光
源ｔは、原稿１を載置するためのコンタクトガラス２の
１つの基準辺に平行にコンタクトガラス２の下方に配置
される。第２図で３は後部反射面、４は主反射面、５は
対向反射面である。照明ブラケット乙にＴｈ＆自在に固
定される点状光源ｔから放射された光は原稿１にて反射
し、主反射面４と対向反射面５の間に設けられたスリッ
ト７を通って第１ミラー８に達する。その際照度ムラを
なくすために、コンタクトガラス２に対して平行にねじ
によって位ｆｋｈ整可能に多分割の照度補正板９が設け
られている。図示していないスキャナは、照明ブラケッ
ト６の腕部６ａにねじによって固定されるスペーサ９と
該スペーサに同様にねじ１１によって固定されるスキャ
ナの受部材１０を介して照明ブラケット６と結合してい
る。First, the configuration of a conventionally known slit scanning illumination device will be briefly described. As shown in FIG. 2, several point light sources t are arranged below the contact glass 2 parallel to one reference side of the contact glass 2 on which the original 1 is placed. In FIG. 2, 3 is a rear reflective surface, 4 is a main reflective surface, and 5 is an opposing reflective surface. The light emitted from the point light source t freely fixed to the lighting bracket B is reflected by the original 1, passes through the slit 7 provided between the main reflective surface 4 and the opposite reflective surface 5, and is reflected by the first mirror. Reach 8. In order to eliminate unevenness in illuminance at this time, a multi-divided illuminance correction plate 9 is provided parallel to the contact glass 2 so that the position fkh can be adjusted by screws. A scanner (not shown) is coupled to the lighting bracket 6 via a spacer 9 fixed to the arm 6a of the lighting bracket 6 with a screw, and a scanner receiving member 10 similarly fixed to the spacer with a screw 11. .

第６図は、上記の如き構成をもつ照明装置を用いた場合
の原稿面照度分布を示した図である。ここでは光源とし
て８個の点状電球を使用し、簡単のために最大原稿幅を
Ａ３とし、小サイズの原稿幅をＡ５とした。各電球を等
間隔に配置し同発光量で点灯させると、結像レンズのコ
サイン４乗則により感光体上での光量分布は不均一にな
る。この光量分布を均一とするためには、例えば光源を
第３図の光源配列（１１のごとく配置すれば、即ち光源
の間隔が端部に向かうに従いしだいに狭くなるように配
置すれば、コサイン４乗則が相殺されて感光体上での光
量分布を均一にすることができる。FIG. 6 is a diagram showing the illuminance distribution on the document surface when the illumination device having the above configuration is used. Here, eight point light bulbs were used as a light source, and for simplicity, the maximum original width was set to A3, and the width of a small-sized original was set to A5. If the light bulbs are placed at equal intervals and lit with the same amount of light, the distribution of the amount of light on the photoreceptor will become non-uniform due to the cosine fourth power law of the imaging lens. In order to make this light intensity distribution uniform, for example, if the light sources are arranged as in the light source array (11) shown in Fig. 3, that is, if the intervals between the light sources become gradually narrower toward the ends, the cosine 4 The multiplicative law is canceled out, and the light amount distribution on the photoreceptor can be made uniform.

この場合の原稿面照度分布は中央部より端部でよシ高く
なる（曲線Ａ）。In this case, the document surface illuminance distribution is higher at the edges than at the center (curve A).

小サイズ（Ａ５）の場合は両端部を照明する必要がない
ので、光源配列（１）においてＡ５のサイズに対応する
電球１３　ｔ　ｚ４ｐ　ｚｓ　ｔ　１６のみを点灯させ
ればよいのであるが、この場合原稿面照度分布は中央部
に比べて端部で低下する（曲線Ｂ）。感光体上の光量分
布を均一にするには、この場合も中央部より端部で原稿
面照度分布を高くする必要がある（曲線Ｃ）。そのだめ
の手段として、電球ｔ３゜Ａ６の電圧を高くし、該電球
ｚ３９１６　の発光量を多くすることが知られている。In the case of a small size (A5), there is no need to illuminate both ends, so it is only necessary to light up only the light bulb 13 t z4p zs t 16 corresponding to the size of A5 in the light source array (1), but in this case The document surface illuminance distribution is lower at the edges than at the center (curve B). In order to make the light intensity distribution on the photoreceptor uniform, in this case as well, it is necessary to make the document surface illuminance distribution higher at the edges than at the center (curve C). As a means to prevent this, it is known to increase the voltage of the light bulb t3°A6 to increase the amount of light emitted from the light bulb z3916.

この解決法は、両端部の電球Ａｌ、　Ａ２　ｐ　７７　
ｙ　Ａ８を点灯させないので電力を半分に節減できるも
のの、点灯回路が複雑となる欠点がある。This solution is suitable for both ends of the bulb Al, A2 p 77
y Since the A8 is not turned on, the power consumption can be cut in half, but the disadvantage is that the lighting circuit becomes complicated.

ところで、原稿面照度を増し曲線Ｃを曲線りまで持ち来
たせば、Ａ５サイズの複写速度を高めることができる。Incidentally, if the illuminance on the document surface is increased to bring curve C to a curved line, the copying speed for A5 size documents can be increased.

ただしこの場合、走査速度、感光体ドラムの周速を対応
的に大きくし且つ定着装置等の電力供給を対応的に処理
するとともに、等倍複写時の原稿面照度分布をそのまま
の状態で変倍複写に適用した場合の周辺光量落ち或は周
辺光量過多を考慮しなければならないが、これは本発明
と直接には関係がないので詳細は省略する。However, in this case, the scanning speed and circumferential speed of the photoreceptor drum are correspondingly increased, and the power supply to the fixing device, etc. is processed accordingly, and the magnification is changed while keeping the illuminance distribution on the document surface unchanged when copying at the same size. When applied to copying, it is necessary to take into account the fall in the amount of peripheral light or the excessive amount of peripheral light, but since this is not directly related to the present invention, the details will be omitted.

曲線りを得るには、次のような手段がある。まず光源配
列（１）において電球ｔ１ないしＡ８を点灯させるため
に必要な電力と同量の電力を電球１３　ｔ　Ａ４　ｔＺ
５　＋　’６に投入する解決法である。しかし、この解
決法は入力電圧が高くなり電球の寿命が短くなるのが欠
点である。The following methods can be used to obtain a curved shape. First, in the light source array (1), the same amount of power as that required to light up the light bulbs t1 to A8 is applied to the light bulbs 13 t A4 tZ.
The solution is to put in 5 + '6. However, this solution has the disadvantage of high input voltage and short bulb life.

さらに、複写サイズに対応して光源を移動させ、例えば
第６図の光源配列ｔｌｌ）のごとく変位させる解決法が
ある。この場合側々の光源に対する電圧は変化させない
で一定としている。各光源を移動可能とするために、保
持部材に保持されている各光源にはレール等のガイド部
材が付設され、そして各光源間にはバネ部材等の弾力性
部材が介在している。この解決法の欠点は、各光源を移
動させるために上記の部拐の他にモータ、プーリ等の駆
動装置をも必要とし、従って光源移動機構が複雑であシ
、構造のための費用が高くなること、さらに各光源間に
弾性部材が設けられているためその負荷変動により光源
の位置の狂いが生じやすいことである。Furthermore, there is a solution in which the light source is moved in accordance with the copy size, for example, as in the light source array tll) in FIG. In this case, the voltages applied to the side light sources are kept constant without being changed. In order to make each light source movable, a guide member such as a rail is attached to each light source held by the holding member, and an elastic member such as a spring member is interposed between each light source. The disadvantage of this solution is that in addition to the above-mentioned components, driving devices such as motors and pulleys are also required to move each light source, so the light source moving mechanism is complex and the construction cost is high. Furthermore, since the elastic member is provided between each light source, the position of the light source is likely to be misaligned due to load fluctuations.

目　的 本発明の目的は、簡潔な経済的な構成によシボサイズ原
稿複写時の省電力化、複写速度の高速化を可能にする複
写機の照明装置を提供することである。OBJECTIVES An object of the present invention is to provide a lighting device for a copying machine that has a simple and economical configuration and can save power and increase the copying speed when copying grain size originals.

構成 本発明の実施例を、第４図および第５図を用いて説明す
る。本発明による照明装置の構成は、光源配列態様を除
いては従来と変わりない。Configuration An embodiment of the present invention will be described using FIGS. 4 and 5. The configuration of the lighting device according to the present invention is the same as the conventional one except for the arrangement of the light sources.

本発明による照明装置では、光源は少なくとも２つの光
源群から構成される。第４図の実施例では、それぞれ同
一の８個の点状電球から成る２つの光源群を使用してい
る。即ち、Ａ３の原稿を照射するためには、第３図の（
１）に対応する第１の光源群１１．　ｌ−ｔ　、　Ａ３
ｔ　ｌ＜　＊　Ａ５ｓ　ｔ６ｔ　Ａ７＊　／−ｓを、Ａ
５の原稿を照射するだめには、第３図の（ＩＩ）に対応
する第２の光学群ｔ１′、ｚｚ’ｔ　７３’ｔ　ｌ−４
’ｐ　ｔ５’、　ｔ６’ｔ　ｔ７’ｊ　’８’を点灯さ
せる。両光源群は同一線上に配列され、回路的には第５
図に示すように並列に接続される。In the lighting device according to the invention, the light source is composed of at least two light source groups. The embodiment of FIG. 4 uses two groups of light sources, each consisting of eight identical point bulbs. That is, in order to irradiate an A3 original, the steps (in Fig. 3) must be performed.
The first light source group 11 corresponding to 1). lt, A3
t l< * A5s t6t A7* /-s, A
In order to irradiate the original No. 5, the second optical group t1', zz't 73't l-4 corresponding to (II) in FIG.
'pt5', t6't t7'j Turn on '8'. Both light source groups are arranged on the same line, and the fifth light source group is arranged on the same line.
connected in parallel as shown in the figure.

その際各光源群・の電球は、コサイン４乗則を考慮して
端部方向へしだい°に間隔が狭くなっていくように配列
される。点灯回路の切換えはスイッチを用いて行なう。At this time, the light bulbs of each light source group are arranged in such a way that the intervals gradually become narrower toward the ends, taking into consideration the cosine fourth power law. Switching of the lighting circuit is performed using a switch.

図示しだ実施例では２つの光源群を配列したが、他の原
稿サイズに対応させてそれ以上の光源群を使用すること
ももちろん可能である。この場合も上記の配列態様、接
続態様を適用し、点灯回路の切換えはスイッチを操作す
るだけでよい。In the illustrated embodiment, two light source groups are arranged, but it is of course possible to use more light source groups to accommodate other document sizes. In this case as well, the above-mentioned arrangement and connection manners are applied, and switching of the lighting circuit can be done by simply operating a switch.

複写サイズとの連動は、転写紙サイズの検知を行ない、
変倍の場合は倍率を検知し連動する必要がある。また、
照明幅とサイトイレース幅を連動させるのが好しい。In conjunction with the copy size, the transfer paper size is detected,
In the case of variable magnification, it is necessary to detect and link the magnification. Also,
It is preferable to link the illumination width and the site erase width.

本発明による照明装置は、原稿台移動型の光学系、リン
ス等の光学系にも適用することができる効果 本発明による照明装置では、照明幅を可変としているだ
め、電力をむだに消費することがなく、さらに小サイズ
複写時には原稿面照度が増すため、複写速度を高めるこ
とができる。The illumination device according to the present invention can also be applied to an optical system of a moving manuscript table type, a rinsing optical system, etc. In the illumination device according to the present invention, since the illumination width is variable, power is not wasted. Furthermore, since the illuminance on the document surface increases when making small size copies, the copying speed can be increased.

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

第１図は原稿台上に各サイズの原稿をセンター基準で縦
置きにした図、第２図は従来の照明装置の断面図、第５
図は従来の照明装置での原稿面照度分布と光源配列態様
を対応させて示した図、第４図は本発明による照明装置
の光源配列態様を示す図、第５図は本発明に用いる回路
図である。 ｔｌ・・・・・・・・・ｔ８・・・Ａ３サイズ複写用光
源群７　、／・・・・・・・・・ｔ８′・・・Ａ５サイ
ズ複写用光源群１５．） 代理人　弁理士　伊　藤　武　久　、：ｌし二」 第２図Figure 1 is a view of originals of various sizes placed vertically on the document table with the center referenced, Figure 2 is a cross-sectional view of a conventional illumination device, and Figure 5 is a cross-sectional view of a conventional illumination device.
The figure shows the correspondence between the illuminance distribution on the document surface and the light source arrangement in a conventional illumination device, FIG. 4 shows the light source arrangement in the illumination device according to the present invention, and FIG. 5 shows the circuit used in the present invention. It is a diagram. tl...t8...Light source group 7 for A3 size copying, /...t8'...Light source group 15 for A5 size copying. ) Agent: Patent Attorney Takehisa Ito, :lshi2" Figure 2

Claims (1)

【特許請求の範囲】[Claims] 複数個の光源を廟する複写機の照明装置に於て、複写サ
イズの大小に合わせて選択点灯される少なくとも２つの
光源群が設けられていることを特徴とする照明装置。1. An illumination device for a copying machine having a plurality of light sources, characterized in that at least two groups of light sources are provided which are selectively turned on according to the size of the copy.