JPH0363676A - Exposure lighting device - Google Patents

Abstract

PURPOSE:To enable exposure lighting by remaining lamps even if one lamp has a disconnection by outputting information of an original size which can be lighted for exposure with the disconnection disconnection detection information. CONSTITUTION:In a normal case, a CPU 13 selects a lamp 1 to be turned on corresponding to original size. For, for example, an intermediate-size original, a signal which turns on lamps NO.1 - NO.3 and turns off a lamp NO.4 is sent to an automatic voltage adjusting device AVR 11. If, for example, the lamp NO.4 has a disconnection, the signal from a means 10 which detects a current becomes 0 and the CPU 13 judges the size of a original which can be irradiated with lamp by the signal from the remaining means 10 and the original is irradiated by th lamp through the AVR 11. Consequently, even if wire breaking occurs to any lamp, the original of size within the range of exposure by the remaining lamps can be irradiated for exposure.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides an exposure illumination device that is equipped with a plurality of lamps, selects and turns on the lamps according to various document sizes, and performs Jifim exposure illumination. do.

[Prior Art] Conventionally, for example, an exposure illumination device for a copying machine includes members such as a lamp 1 and a reflector 2, as shown in FIG. In the figure, a document placement plate 3 is provided at the top of the copying machine, and a document 4 is placed on it. FIG. 3 is an enlarged perspective view of the lamp 1 and the reflector 2, in which a plurality of lamps 1 are arranged in a horizontal row. By appropriately selecting the lamp group 1 arranged in this row, as shown in FIG. irradiate light on the target. For example, in the case of a medium-sized document, lamps 1 of N001 to N094 are turned on to perform exposure illumination. At that time, the N005.60 lamp is turned off. In this way, the exposed light is
The light is irradiated onto the photoreceptor 9 through the reflection mirror 5, the imaging lens 6, and the reflection mirror 7.8, and a latent image of the original image is formed thereon (see Japanese Patent Laid-Open No. 176632/1983).

[Problems to be Solved by the Invention] By the way, for example, when the lamp 1 of No. 1 is disconnected, the above-mentioned conventional exposure illumination device treats this as an abnormality and stops copying altogether.

However, if only the lamp L of N006 is broken, as is clear from the above, it is possible to expose and illuminate the medium-sized or small-sized original 4, even though it is impossible to expose the large-sized original 4. . Despite this, conventionally, copying has been completely stopped.

The present invention aims to solve the problems of the prior art.

[Means for Solving the Problems] The present invention provides an exposure illumination device that includes a plurality of lamps, selects and lights up the lamps according to various document sizes, and performs exposure illumination of the document (1). A wire breakage detection means detects a wire breakage in the front Q lamp, and based on the information detected by the wire breakage detection means, outputs size information of the document on which image formation is possible or impossible, and also outputs wire breakage information if there is a wire breakage. This is an exposure illumination device characterized by comprising: a determining means for outputting a .

[Function] The present invention provides an exposure illumination device that includes a plurality of lamps, selects and lights up the lamps according to various document sizes, and performs exposure illumination of the document. Based on the information detected by the wire breakage detection means, the determining means outputs size information of the document that can be exposed or illuminated, and also outputs wire breakage information if there is a wire breakage.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic block diagram showing an embodiment of an exposure illumination device according to the present invention.

In the figure, lamps 1 No. 1 and No. 2 expose and irradiate a small-sized original 4, lamps No. 1-No. 3 expose and irradiate a medium-sized original 4, and lamps No. 1 to No. 084 1 is for exposing and irradiating a large-sized original 4. Each lamp N091 to N094 has a lead wire 1.
It is connected to an AVR (automatic voltage regulator) 11 through 01.102.103.104, and further connected to a power supply 14. The AVR II is a circuit that selectively turns each lamp 1 on and off according to a signal from a CPU (central processing unit) 13. 12 is an I10 interface of the CPU 13.

Each of the lamps N091 to N014 is equipped with a current sensor 10 that detects the current flowing therein, which is an example of a disconnection detection means that individually detects a disconnection of the lamp l. The current signal detected by the current sensor 10 is transmitted to the I10 interface 12.
It is connected to the CPU 13 via.

Note that the size of the document 4 is provided to the CPU 13 by a known automatic document size reading device or by the operator's operation of keys on the operation panel.

The CPU 13 is a means for implementing various means such as the determination means described below in software, using storage means such as RAM and ROM.

Next, the operation of the exposure illumination apparatus of the present invention will be explained in accordance with the above embodiment.

During normal copying, the CPU 13 selects the lamp 1 to be lit in accordance with the document size provided as described above. For example, for a medium-sized document, N00
A signal is sent to the AVRII to turn on the lamps 1 to N003 and turn off the lamps No. 4. In this state, the optical systems 1 and 2 are caused to scan below the original 4. by this,
This prevents unnecessary lighting of lamps.

Next, for example, when the lamp NO, 4 is disconnected, the signal from the current sensor lO, which detects the current of the lamp NO, 4, becomes zero. The CPU 13 uses this current sensor 1
0 and the signals from the other current sensors 10, the remaining lamps N091 to N0.3 determine the document size that can be exposed.

Then, if the provided document size is a document size that can be exposed and irradiated, the CPU 13 sends a signal to the AVR II to perform exposure irradiation for normal copying.For example, if the document size is small or medium, normal copying is Since this is possible, exposure irradiation is performed.

On the other hand, if the document size is large, the entire surface cannot be exposed, so copying is not performed.

At the same time, a warning to the effect that the wire has been disconnected is displayed using liquid crystal or LED means.

Therefore, for example, if lamp No. 1 is disconnected, copying of originals of all sizes is prohibited.

Note that the permitted document size is not limited to those shown in the above example, but may vary depending on the number of lamps, their arrangement, the position where the document is placed, etc. Needless to say, it is selected as appropriate.

Further, as the wire breakage detection means, not only the current sensor but also other known wire breakage detection means may be used.

In the above embodiment, a microcomputer is used as the determination means, but a dedicated discrete circuit may be used for such determination means.

[Effects of the Invention] As explained above, the present invention detects lamp breakage, determines the size of the document on which image formation is possible or not, and outputs breakage information if there is a breakage. ,
This is convenient because even if some of the lamps are broken, the remaining lamps can be used to expose and irradiate documents of a size within the range that can be illuminated.

[Brief explanation of drawings]

FIG. 1 is a schematic circuit diagram showing an embodiment of an exposure illumination device according to the present invention, FIG. 2 is a schematic sectional view of a copying machine, and FIG. 3 is a perspective view of a lamp of the copying machine. FIG. 4 is a plan view showing the relationship between the lamp and the document. l...Lamp 4...Document 10...Current sensor (disconnection detection means) 13...
CPU (judgment means)

Claims (1)

[Claims] In an exposure illumination device that includes a plurality of lamps and selects and lights up the lamps according to various document sizes to expose and illuminate the document, a disconnection detection means detects a disconnection of the lamp, and the disconnection detection means detects a disconnection of the lamp. An exposure illumination device characterized by comprising a determining means for outputting size information of a document on which image formation is possible or impossible based on the detected information, and outputting disconnection information when there is a disconnection.