JPS62192767A - Side erasing device for copying machine that executes zoom variable magnification - Google Patents

Abstract

PURPOSE:To erase black borders at high accuracy by simple means by using in combination of erasing by a reflecting plate at the end and an erasing lamp. CONSTITUTION:Light reflected by the reflecting face 17A of a reflecting plate 7 irradiates the face of an original directly, and light reflected by the reflecting face II 7B is reflected by an auxiliary reflecting plate 9 and irradiates the original face. End reflecting plates 18 are provided on both ends of an illuminating section, and the light receiving face 18A is slanted to receive light reflected from the reflecting face II 7B of the reflecting plate 7 and expose a photosensitive body directly through a lens 1. Accordingly, sufficient light can be irradiated on the end part outside of a picture exactly, and a specified extent can be erased. When variable magnification, it is possible to erase specified width automatically outside of the picture, and accordingly, it is enough to make the width of a white member that covers the original face slightly larger than the largest width of the original.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a side erase device for a copying machine that performs zoom magnification.

(Prior Art) As shown in FIG. 13, there are a shutter plate interlocking method, a small pitch LED eraser, etc. as side erase methods to completely cope with changes during copying due to the magnification during zooming/reduction. The former uses a single motor and has an electrical interlocking means and a mechanical variable magnification mechanism and interlocking means, but both complicate the device and increase costs. In the latter case, the cost of the LED itself is high and the wiring control becomes complicated.

Also, as shown in Fig. 14, a commonly used method is as follows.
Combine a split LED and a white document cover, cover the outside of the largest document with a pressure-reduced white sheet or ADF white belt, and expose the reflected light from the white portion through the lens to cover a predetermined width (A) outside the image on the side. In combination with an LED eraser with a relatively rough pitch, black frames are erased during zoom magnification. (Erasing in the scan direction is easy with the eraser lighting timing.) However, the pitch of the D eraser (LED) is small (a small pitch is high cost), so the side erase width outside the image ( Therefore, the rlJ of the white part of the pressure plate or ADF becomes larger, and the device becomes larger.

■ If the white section of the pressure plate or ADF is insufficient (dimension),
The erase by the erase lamp digs into the image (portion B), and depending on the magnification, white spots may occur.

(2) The area indicated by copy 0 is an area where an image is captured, but since it is outside the effective image, the illuminance is insufficient and background smear occurs.

There was a problem.

Furthermore, as shown in Japanese Patent Application Laid-open No. 55-142365, a reflection plate is installed at the longitudinal end of the slit between the light source and the document surface, and the direct light from the light source is reflected by the reflection plate, and the light is transmitted through the imaging element. There is also a known method for forming white gaps at the edges of the body, but although it has a side erase function when using end face reference at the same magnification, it does not have a side erase function when using variable magnification copying or center reference copying. There was a problem.

(Purpose) The present invention enables a copying machine that performs zoom magnification to erase black frames by automatically erasing the outside of the effective copying area in conjunction with changes in each magnification ratio, and By reducing the width of the white member at the end of the plate, reducing the width of the contact glass, the pressure plate, the document transport device, etc., the entire device is made smaller.
It is an object of the present invention to provide an inexpensive device that can erase black frames with high precision using simple means.

(Structure) The present invention aims to solve the above problems,
Stepwise variable copying between normal size and reduction (e.g. 1% to 0.1%)
In a slit exposure copying machine that is capable of a slit-exposure copying machine that is capable of The lighting means includes a first reflecting surface that surrounds the light source and focuses the light from the light source directly onto the document surface, and a first reflecting surface that focuses the light from the light source directly onto the document surface. A reflective member having a second reflective surface that reflects light and is inclined so that the reflected light from the second reflective surface is irradiated onto the image forming member through the imaging means is attached to the slit at the longitudinal end of the slit at the bottom of the document surface. By placing the inner end surface so that it coincides with the effective imaging light flux, the effective imaging ratio at each magnification is naturally linked to the change in magnification between normal magnification and reduction. The present invention is characterized in that it irradiates a predetermined range outside the copy area and erases the black frame together with the erase means.

Hereinafter, a detailed explanation will be given based on the illustrated embodiment. FIG. 1 shows a well-known document moving copying machine embodying the present invention. The document table 2 is driven by a single servo motor, and its speed is variable when changing the magnification. When changing the magnification, the lens 1 and the third mirror 5 are moved in parallel to the horizontal direction. When changing magnification, the lens and third mirror are linked with a cam and driven by one stepping motor to perform zoom magnification (the lens and third mirror may be driven by separate stepping motors). When changing the magnification, the third mirror 5 moves, so that the image forming point on the photoreceptor surface moves from point A at the same magnification to B or to point 0. The photoconductor is belt photoconductor 1
0 is used, and an erase lamp 16 is installed behind (or in front of) the exposure section to perform front and rear end erase (scan direction) and side erase. Since the imaging point on the photoreceptor moves due to magnification, the timing of leading and trailing edge erase is changed according to the magnification.

As shown in FIG. 2, the light reflected from the reflective surface 17A of the reflective plate 7 directly illuminates the original surface, and the light reflected from the 1 reflective surface n7B is reflected by the auxiliary reflective plate 9 and illuminates the original surface. reflective surface I,
■It has a co-elliptical conformal circular shape, and the light is focused on the document surface. The slit is formed by the end portion 7C of the reflecting plate 7 and the slit regulating plate 17. The light source uses a rod-shaped halogen lamp.

Next, FIGS. 2 and 4 will be explained. As shown in FIG. 3, end reflectors 18 are installed at both ends of the lighting section.
The light receiving surface 18A is inclined so as to receive the reflected light from the reflecting surface II 7B of the reflecting plate 7 and directly expose the photoreceptor through the lens 1. Further, the tip portion 18B is a reflective surface 1.
In a position that does not block the 7A document surface illumination light, and also on the reflective surface I.
It is set at a position that sufficiently receives the reflected light from f7B and also sufficiently covers the slit width.

If the light from the reflective surface 1 7A is blocked, the illuminance at the inner edge of the image will be insufficient, and the light received by the reflective surface II 7B will be insufficient, and if the width of the end light receiving surface 18A is narrower than the slit width, the erase light will be insufficient. . The light receiving surface 18A of the end reflector 18 is formed of a white diffuse reflection surface. This is because the light source is a halogen lamp (point light source), and in the case of a mirror surface, the light spreads due to regular reflection and cannot illuminate a predetermined area. In the case of fluorescent lights, a mirror surface is also fine.

As shown in FIG. 3, the end reflector is arranged so that the upper part is in contact with the light beam at the same magnification. With the above configuration, sufficient light can always be accurately irradiated to the edge outside the image, and a predetermined range can be erased. Since the reflected light from the end reflector passes through the lens and illuminates the photoreceptor, it is possible to automatically erase a predetermined width (C-D) outside the image when changing the magnification (reduction) as shown in Figure 4. Therefore, if the width of the white member 20 that covers the document surface is made slightly larger than the maximum document surface (A=1 to 21II11), sufficient coverage can be achieved. (The width of the white member can be made smaller.) The width of the edge reflected light when reduced is the value obtained by multiplying the width C when the image is magnified at the same magnification by the magnification m.

D=mXC (m=magnification) The erase lamp 16 is provided with a partition 16A.

Lighting is controlled in response to changes in magnification. For example, magnification 0
．． 5 to 0.6, the blocks B+C+D are lit.

The erase lamp 16 may be divided relatively roughly, since a sufficient period of time during irradiation of the end reflected light can be ensured. Since the end reflector is installed close to the document surface and passes through the lens, even if there is an error in magnification, the outside of the image can be accurately erased, eliminating problems caused by misalignment between the erased image and the image (white spots).

black belt). FIG. 9 shows an example of the occurrence of black bands due to misalignment between the erase and the image when copying is performed using A3 transfer paper with reduction from A3 to A4.

As shown in FIG. 5, if the thickness of the end reflector is thick, a shadow will be generated between the erase irradiation light of the end reflector 18 and the image, resulting in a thin (about 0.5 mm) black stripe on the image. The thickness is kept as thin as possible. (0,05~0,1 rrn) Also, as shown in Fig. 6, as a method to prevent the above-mentioned shape, the erase irradiation light from the end reflector is tilted with respect to the exposure slit (B: 1 + nm, 8 in Fig. 3). It can also be erased by increasing the size (approximately 1 nwn).

The end reflected light uses the reflected light from the reflective surface ff7B of the reflective plate 7 shown in FIG. In other words, since part of the light that illuminates the original is blocked, the illuminance decreases at the edges of the image (as shown in Figure 8).
10%).

The reduction in illuminance at the ends can be improved by adjusting the installation conditions of the end reflectors, but methods for further improvement are described below.

In FIG. 7A, the light from the light emitting point 8A at the end of the illumination lamp 8 is blocked by the end reflection plate 18, and the area A on the document surface becomes a shadow.

In FIG. 7B, by moving the light emitting point 8B at the end of the illumination lamp 8 inward and bending the end 9A of the auxiliary reflector 9, the shadow of the end reflector 18 moves to the outside of the edge of the document. A decrease in illuminance at the inner edge of the effective image can be prevented.

Note that it is possible to prevent the illuminance from decreasing at the inner edge of the image by making the edge reflector semi-transparent or partially transmitting light, but in this case, there is insufficient erase light and the outer edge of the image is Background stains occur due to decreased illuminance.

If the auxiliary reflector 9 in FIG. 2 is removed, the illumination efficiency will be reduced by about 10 to 20% because there will be no document illumination light from the auxiliary reflector as shown in FIG. Since the light is not blocked by the edge reflector 18, the edges of the document surface can be sufficiently illuminated and no shadows are generated.

As shown in Figure 11, when using the center reference, the angle of view changes between normal magnification and reduction, and the amount of penetration A of the end reflector into the luminous flux during reduction depends on the magnification, lens focal length, and FAfiOi surface. Although it varies depending on the distance, it is usually less than 1 meter without any problem.

As shown in Figure 12, in the case of end face reference, the deviation of the luminous flux on the reference side is small, but on the side opposite to the reference side, the luminous flux changes greatly between when the magnification is the same and when it is reduced, and the amount of penetration C of the end reflector is It will be about 3 to 5 meters. For this reason, in the case of end face reference, it is necessary to move at least the end reflector on the side opposite to the reference side in stages in conjunction with the magnification.

Note that the present invention applies to both optical system movable copying machines and edge-based copying machines.
A zoom lens may also be used.

(Effects) According to the present invention, it is possible to perform stepwise scaling reproduction between the same size and reduced size (e.g.
1% to 0.1%), an image forming member that forms an original image, an imaging means that projects the original image onto the image forming member, and an illumination means that illuminates the original. and,
The illumination means includes a first reflecting surface that surrounds the light source and focuses the light from the light source directly onto the document surface, and a first reflecting surface that surrounds the light source and focuses the light from the light source directly onto the document surface. A reflecting member having a second reflecting surface that reflects a part of the light, and which is inclined so that the reflected light from the second reflecting surface is irradiated onto the image forming member through the imaging means, is attached to the longitudinal side of the slit at the bottom of the document surface. By covering the directional end with a slit and placing the inner end surface so that it coincides with the effective imaging light beam, it is inevitably linked to the change in magnification between 1-1 magnification and reduction. A predetermined range outside the effective copying area at each magnification is irradiated and the black frame is erased together with the erase means. By using it in conjunction with a lamp,
It is possible to reduce the width of the document white member (ADF belt, etc.), the width of the contact glass, the pressure plate, the vA document conveyance device, etc., the device can be made smaller, and the complicated method (shutter plate interlocking, etc.) can be made smaller. Even without using a black frame at the edge, it is possible to erase the black frame at the edge with high accuracy, and the entire device can be provided at a low cost.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the operation of a well-known document moving type copying machine embodying the present invention, FIG. 2 is a sectional side view of the first embodiment of the illumination section of the present invention, and FIG. 3 is a position of the end reflector of the present invention. 4th plan view showing
5 is a front view of the erase irradiation light of the end reflector, FIG. 6 is a diagram showing the erase irradiation light from the end reflector tilted with respect to the exposure slit, and FIG. Figure A is a diagram showing that the light from the light emitting point of the illumination lamp is blocked by the end reflector and the area A on the document surface is in shadow.
Figure B is a diagram of Figure 7 A with the end reflector plate bent to eliminate shadows, Figure 8 is a diagram showing the position in the image and illuminance, and Figure 9 is A3 →
Diagram 1 showing a state in which a black band occurs in an A4 size image when reduced.
Figure 0 is a diagram with the auxiliary reflector in Figure 2 removed, Figure 11 is a diagram showing the amount of penetration of the end reflector into the luminous flux when the center reference is made, and Figure 12 is the end reflector when the end face is referenced. FIG. 13 is a diagram illustrating the principle of a conventional shutter plate interlocking method. FIG. 14 is a diagram illustrating the principle of an erasing means using a combination of a conventional divided LED and a white document cover. 1a...Lens equal magnification position 1b...Lens reduction position 1c...Lens enlargement position 2...Original platen 3...
1st mirror 4... 2nd mirror 5... 3rd mirror 6... 4th mirror 7... Reflector
8...Illumination lamp 10...Photoreceptor belt
16... Erase lamp 18... End reflector
19... Original 20... White member Fig. 1 Fig. 2 Fig. 3 Fig. 2 ゛ Fig. 4 Fig. 5 A Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 1O Fig. 1/Fig. Figure 12

Claims (1)

[Claims] Stepwise variable copying between normal size and reduction (e.g. 1% to 0.1%)
In a slit exposure copying machine that is capable of a slit-exposure copying machine that is capable of The lighting means includes a first reflecting surface that surrounds the light source and focuses the light from the light source directly onto the document surface, and a first reflecting surface that focuses the light from the light source directly onto the document surface. A reflective member having a second reflective surface that reflects light and is inclined so that the reflected light from the second reflective surface is irradiated onto the image forming member through the imaging means is attached to the slit at the longitudinal end of the slit at the bottom of the document surface. By placing the inner end surface so that it coincides with the effective imaging light flux, the effective imaging ratio at each magnification is naturally linked to the change in magnification between normal magnification and reduction. A side erase device for a copying machine that performs zoom magnification, characterized in that it irradiates a predetermined range outside a copying area and erases a black frame together with the erase means.