JPS58106565A - Scanning exposure device of copying machine - Google Patents

Abstract

PURPOSE:To increase easily a copying speed, by making at least one angle of a moving mirror and a relaying mirror variable when a going-motion of a scanning system is started, constituting a titled device so that a reflected ray from an original is not made incident to a photosensitive body side. CONSTITUTION:In the first and the second scanning systems 7, 12, for instance, the second relaying mirror 11 is constituted so that its angle can be varied. That is to say, to a moving body 14 which moves in the direction opposite to a photosensitive body 13 at a speed v2, one end side of the second relaying mirror 11 is pivotally attached by a pin 15, and also on the floating end side of the second relaying mirror 11, a stopper 16 for controlling the moving range is provided. Alos, the second relaying mirror 11 is always energized to a virtual line position by a spring 17, also the back face of the second relaying mirror 11 is electrified at the time of scanning of the going-path of the first and the second scanning systems 7, 12, the second relaying mirror 11 is held at a full line position, and when the electric conduction is out off, the reflected ray is refracted to a wall surface 19a side of a slit 19.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying-like scanning exposure apparatus that enables high-speed copying.

2. Description of the Related Art A conventional scanning exposure device for a copying machine is shown in FIG. 1, for example. The scanning exposure device includes a first movable mirror b that moves at a speed V along the original document α to be copied;
It includes a second movable mirror C and a lens d that move at 1/2 the speed of the movable mirror h, and a photoreceptor e also moves in the scanning direction at a speed υ. If you try to increase the copying speed with such a scanning exposure device, you will have to increase the speed υ of the first movable mirror b + photoreceptor e, which will cause image deterioration due to vibrations during scanning, etc. The accuracy of the system must also be improved, which makes it expensive.

To improve this problem, as shown in FIG. 2, the first movable mirror b, ty moves in the opposite direction. 2nd relay mira f.

! has been proposed. In such a scanning exposure device, the first and second movable mirrors h and c are the third movable mirrors when scanning an original.
Move along the route shown in Figure A. 2nd relay mira f,
Move along the route shown in Figure 3B. That is, the first. The second movable mirrors h and cVi scan the document α at a relatively slow speed on the outward path (a), and return to the original position on the return path (b) at a faster speed than the forward path (a). Also number 1. 2nd relay Mira f, yake 1st. It moves in the opposite direction to the second movable mirror h, c, and returns at a faster speed on the return trip (b) than on the outbound trip (a).

However, in such a scanning exposure system, the first and second relay mirrors f
,! When the photoreceptor 1 returns, the latent image formed on the photoreceptor C during the forward pass is scanned twice in the shaded area in FIG. 3, causing the problem that the latent image is disturbed. Note that a dotted line C indicates the movement of the photoreceptor e.

This invention was made for the purpose of improving the problems caused by this invention. When the second scanning system consisting of the second relay mirror returns from the forward path to the return path, the angle of at least one of the movable mirror straddling relay mirrors is temporarily changed so that the reflected light from the original enters the photoreceptor. It is an object of the present invention to provide a scanning exposure device for a copying machine that prevents overlapping of parts of an original image when the scanning system changes from one forward path to the other.

An embodiment of the present invention will be described below in detail with reference to the drawings shown in FIG. .

The two originals on the platen 3 are exposed by an exposure lamp (not shown) that moves along the two surfaces of the original, and the light reflected from the original 2 is reflected by a first movable mirror 4 that moves in the direction of the arrow at a speed υ1 together with the exposure lamp. The second movable mirror 5, 6
refracted to the side. The second movable mirrors 5 and 6 constitute a first scanning system 7 together with the first movable mirror 4, and the speed of the second movable mirrors 5 and 6 is 1/2 that of the first movable mirror 4, that is, -
to move in the direction of the arrow. Further, the reflected light refracted by the second movable mirrors 5 and 6 passes through the fixed lens 8 and passes through the first relay mirror 9.
．． io, where it is refracted toward the second relay mirror 11 side. 1st ° 2nd relay Mira 9, 10. l l is the second scanning thread 1
2, the first relay mirror 9 and 10 are the same as the first
7 in the opposite direction to the scanning system 7, and 11 in the same direction as the second relay mirror 11. The reflected light reflected by the first relay mirrors 9 and 10 is irradiated via the second relay mirror 11 onto the photoreceptor 13, which moves at a speed υ0 in the same direction as the first scanning system 7. - An electrostatic latent image is formed on the photoreceptor 13.

On the other hand, the above 1. Among the second scanning systems 7 and 12, for example, the second relay mirror 11 is constructed so that its angle can be varied as shown in FIG. In other words, the speed V! One end of the second relay mirror 11 is pivotally attached to the movable body 14 moving in the opposite direction to the photoreceptor 13 by means of a bottle 15, and a stopper is provided on the free end side of the second relay mirror 11 to restrict the re-movement range. 16
is provided. In addition, the above-mentioned second relay mirror 11
7 to the position shown in the imaginary line in FIG. Second scanning system 7,1
A drive means 1g, such as a solenoid, is provided, which is energized during the outward scan of step 2 to hold the second relay mirror 11 at the position shown by the solid line in FIG. The reflected light is refracted toward the wall surface +qa side of the slit 19.

Note that the first thing. The forward path of the scanning timing of the second scanning systems 7 and 12 is shown in FIG. 6(A), the backward path is shown in FIG. 6(B), and the driving timing of the driving means 18 is shown in FIG. 6(C). Further, in the above embodiment, the angle of the second relay mirror 11 is movable, but it is of course possible to vary the angle of the first and second movable mirrors 5, 6 or the first relay mirror 9°10.

As described in detail above, the present invention is applied to the first scanning system 7 which guides the reflected light from the original 2 to the photoreceptor I3 during the scanning of the original 2.
The second movable mirror 4,5.6 or the first mirror of the second scanning thread 12.
The angle of at least one of the second relay mirrors 9° to, l + is adjusted to the angle of the first. When the second scanning systems 7 and 12 are switched from the forward path to the backward path, the reflected light from the document 2 is reflected onto the photoreceptor 1.
3, there is no risk that the electrostatic latent image formed on the photoreceptor 13 during the forward journey will be distorted during the return journey. As a result, copying speed can be easily increased by using the scanning exposure apparatus of the present invention.

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams of a conventional scanning exposure device;
The diagrams are diagrams showing the operation of the scanning exposure device shown in Figure 2, and Figure 4.
The figure is a configuration diagram of a scanning exposure apparatus which is an embodiment of the present invention.
FIG. 5 is an enlarged view of the main parts, and FIG. 6 is a diagram showing the operation timing. 2 digit original, 3 digit platen, 4 digit first movable mirror, 5.6 digit second river moving mirror, 8 digit fixed lens, 9° 10 digit first relay mirror, 11 digit second relay mirror, 13 digit photoreceptor . Applicant Fuji Xerox Co., Ltd. Agent Patent Attorney Masaaki Yonehara Patent Attorney Tadashi Hamamoto Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 FF C-11)

Claims (1)

[Claims] A first movable mirror 4 located below the platen 3 on which the original 2 to be copied is placed and moves at a speed v;
The second movable mirrors 5 and 6 move in the same direction at half the speed of the movable mirror 4, and the reflected light from the first movable mirror 4 and the second movable mirror 5 and 6 is moved in the opposite direction 7. It is guided to the first relay mirror 9, 10 side which moves at a speed of
Speed υ in the same direction as the first relay mirrors 9 and 10. The photoreceptor 1 moves at a speed Zlo and moves the reflected light from the first relay mirrors 9 and 10 in the same direction as the first movable mirror 5.
The second middle i-mirror 11 refracts toward the third side, and the first one. 2nd town moving mirror 5, 6.7 and 1st second relay mirror 9, 10. I+
and the photoreceptor 13 is v, = υ, 10v, (where 0〈υ〦
vI), which is equipped with a drive system that drives at a speed related to the above-mentioned item 1. The second movable mirror 5, 6.7 and the first movable mirror.
2nd middle M: Mira 9. A scanning exposure device for a copying machine in which at least one angle of to and l+ is varied at the start of forward movement of a scanning system to prevent reflected light from an original 2 from entering a photoreceptor 13 side.