JPH04296739A - Image forming device - Google Patents

Abstract

PURPOSE:To preven the whole of the device from being made large-sized even when a light shielding device for eliminating a black frame or the like is provided for a print image in a reader printer. CONSTITUTION:A pair of plate-like shutters 32 and 34 which can be mutually slid in an opposite direction on a substrate 31 which is vertical to an optical path by the turning of an operation knob 37 is arranged and a flexible light shielding sheet 33 is arranged integrally with the shutter 32 on the optical path which is positioned on a downstream side from a projection lens and which is used in common at a reader time and a printer time.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a reader state in which an image on an image support such as a microfilm is projected onto a screen and observed, and a printer state in which the image is projected onto an exposure section to obtain a copied image. The present invention relates to an image forming apparatus that can be switched to.

0002

2. Description of the Related Art In general, most of the images recorded on microfilm are negative images, and a so-called reversal development method is used to obtain a copy of a positive image from this negative image. In this reversal development method, when copying is performed using an electrophotographic copying method, development is performed by applying a developing toner having the same polarity as the electrostatic latent image to an electrophotographic photoreceptor on which an electrostatic latent image has been formed. In other words, after uniformly charging the photoreceptor, a negative image on a microfilm is exposed to the photoreceptor, leaving a charge on the unexposed area of the photoreceptor, which is charged to the same polarity as the charge remaining on the exposed area of the photoreceptor. Development is performed by adhering the toner. Microfilms with negative images generally have negative images recorded in frame f of microfilm F, as shown in FIG. 6, and opaque search marks M and frame numbers N are recorded around each frame. There is. Normally, in reader printers that use microfilm, an area larger than one frame of microfilm is projected onto the photoreceptor, and
The size of the image recorded in one frame also varies.

In such a reader printer, when a negative image on a microfilm is projected onto a photoreceptor and developed using a reversal development method, toner adheres to an area corresponding to the outside of one frame of the image on the photoreceptor. A so-called black frame is recorded around the image on the photoconductor, and search marks and frame numbers are also recorded, which makes it look bad.
There are problems such as a decrease in the commercial value of the copy and, in the case of electrophotographic copying, an increase in the amount of toner consumed.

[0004] To solve this problem, it is possible to place a mask on the surface of the microfilm with an opening corresponding to the size of the microfilm, but with this method, the mask must be changed every time the size or reduction ratio of the image area changes. In addition, since the search mark and the piece number are no longer projected on the screen, it is no longer possible to search for information using the mark and the piece number. In addition, before printing, the image on the film is scanned with a light sensor to detect the size of the area, and depending on the detected size, the timing of opening and closing of the exposure shutter is controlled in the direction in which the printer transfers the transfer material. However, for the width direction of the transfer material, a method has been proposed in which the black frame is removed by controlling the position of a light shielding member for regulating the width direction provided near the exposure slit, but in this case, the structure and operation are complicated. Furthermore, since the area to be printed cannot be visually observed on the screen, it is necessary to check the printed image each time it is printed. As a means to solve this drawback, it has been proposed to arrange a light shielding means to narrow down the light beam on the optical path that is common to the reader and printer.

[0005]

[Problems to be Solved by the Invention] However, this means tends to increase the size of the light shielding device, and as a result, in order to arrange this device on a common optical path for the reader and printer of the image forming device, it is necessary to This has the disadvantage that the entire device must be enlarged.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the drawbacks of the prior art described above and to provide an image forming system that allows the entire apparatus to be miniaturized even when a light shielding member is used.

[0007]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention provides a reader state in which a negative image recorded on a microfilm is projected onto a screen and observed by a projection lens; In an image forming device that can be switched to a printer state by projecting an image onto an exposure unit to obtain a copy, a light source located downstream of the projection lens and on the optical path that is common to the reader and printer is perpendicular to or close to perpendicular to the optical path. A plate-like light-shielding member and a sheet-like light-shielding member that can slide on an angled plane are arranged.

[0008]

[Operation] Since the image forming apparatus constructed as described above uses a plate-like or sheet-like light-shielding member that slides on a plane, it can be installed in a narrow space in the optical axis direction, making the entire apparatus compact.

[0009]

[Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. 1 to 5.
The explanation will be based on. The figures show a reader printer as an image forming apparatus, FIG. 2 is a schematic side view thereof, and FIG. 3 is a schematic front view of FIG. 2 viewed in the direction of arrow A. In Figure 2, F is a microfilm, 1 is a lamp, 2 is a reflector, and 3
is a condensing lens, 4 is a field lens, and 5 is a projection lens. The entire image of one frame of the microfilm F is illuminated by the lamp 1, and the illuminated frame image is exposed to the projection lens 5.
is projected onto the reader optical path or printer optical path, which will be described later. The reader optical path is formed by the first reflecting mirror 11, the second reflecting mirror 12, the third reflecting mirror 13, and the fourth reflecting mirror 14, which are fixed at the positions shown in the figure, and the printer optical path is formed by the first reflecting mirror 11, the second reflecting mirror 12, the third reflecting mirror 13, and the fourth reflecting mirror 14, which are fixed at the positions shown in the figure. It is formed of two reflecting mirrors 12, a fifth reflecting mirror 15, and a sixth reflecting mirror 16 shown in FIG. The reflecting surfaces of the fifth and sixth reflecting mirrors 15 and 16 form an angle of 90° with each other, and can integrally move back and forth between the solid line position and the broken line position in the direction of the arrow in FIG. In addition, the fifth and sixth
The reflecting mirrors 15 and 16 are located in an area B1 surrounded by a broken line in FIG.
will be reciprocated in the vertical direction with respect to the plane of the paper. Further, 20 is a screen, 21 is a photosensitive drum disposed in an exposure section, and 22 is a slit plate provided in front of the photosensitive drum 21.

In the reader mode, the fifth and sixth reflecting mirrors 15 and 16 are stationary at the solid line positions outside the optical path, and the image light of the microfilm F passes through the projection lens 5 and is reflected by the first mirror.
From the reflecting mirror 11 to the second, third, and fourth reflecting mirrors 12, 13, 1
4 onto the screen 20. On the other hand, during printing, the fifth and sixth reflecting mirrors 15 and 16 move in the direction of the arrow and in the direction of the broken line, and pass through the projection lens 5 and pass through the first and second reflecting mirrors 11 and 12 to reflect the image light. The reflected light passes through the slit plate 22 and is scanned and exposed onto the photosensitive drum 21, which rotates clockwise. Then, when the fifth and sixth reflecting mirrors 15 and 16 come to the exposure end position shown by the broken line, the scanning exposure of the image is completed, and then the fifth and sixth reflecting mirrors 15 and 16 return to the solid line position, Switch to reader mode. However, the fifth and sixth reflecting mirrors 15 and 16 move in the direction of the arrow at a speed of 1/2 of the circumferential speed of the photosensitive drum 21 to perform exposure scanning. Known image forming means such as a charging device, a developing device, and a transfer device (not shown) are arranged around the photosensitive drum 21, and copying is performed by electrophotography.

Here, a region B2 surrounded by a broken line in FIG. 2 is on the downstream side of the projection lens 5 and is on the common optical path for the reader and printer. By arranging a light shielding device, which will be described later, in this area B2, it is possible to erase the black frame that appears on the printer, and it is also possible to confirm the light shielding state on the screen in advance. FIG. 1 shows a perspective view of a light shielding device 30 and a portion of the fourth reflecting mirror 14 adjacent to the light shielding device 30. In the figure, reference numeral 31 denotes a board for fixing each component constituting the light shielding device 30 and mounting it on the main body of the image forming apparatus, and is arranged below the fourth reflecting mirror 14 so as to be substantially perpendicular to the optical path. It is made of a plate having an aperture 31a that is equal to or larger than the maximum effective luminous flux area of the image projection optical path, and pins 31 are arranged parallel to each other on both sides of the plate.
b, 31c and 31d, 31e are fixed. 32
The first shutter is made of a plate-shaped light shielding member having a guide hole 32a, and the pin 3 of the substrate 31 is inserted into the guide hole 32a.
1b and 31c are engaged and can be slid in the direction of arrow a or b, and a light shielding sheet 33 made of a flexible and opaque sheet material is adhered to the light shielding part and integrated. It is supposed to move. 34 is the second shutter,
It is made of a plate-shaped light shielding member having a guide hole 34a, and the pins 31d and 31e of the board 31 are engaged with the guide hole 34a so that they can be slid in the direction of the arrow a or b. Furthermore, the first shutter 32 and the second shutter 34 are
A guide hole 35a with which a pin 32b fixed to the shutter 32 engages and a pin 34b fixed to the second shutter 34
are connected by a connecting plate 35 having a guide hole 35b that engages with the connecting plate 35. The connecting plate 35 is provided with a rotating shaft 36 having an operating knob 37 between the guide hole 35a and the guide hole 35b, and when the operating knob 37 rotates about the rotating shaft 36, the first shutter is rotated. 32 and second shutter 34 slide in opposite directions.

The operation of this embodiment having the above configuration will be explained using FIGS. 4 and 5. Usually, the first shutter 32 and the second shutter
The shutter 34 is placed at the position shown in FIG.
It is not blocked by the shutter 34, and the entire effective light flux area of the negative image and its periphery can be projected onto the screen 20 or the photosensitive drum 21. A broken line C indicates the lower end of the maximum effective light flux from the fourth reflecting mirror 14 toward the screen 20. If you want to avoid forming a black frame during printing or erase a part of the image, turn the operating knob 37 clockwise to move the first shutter 32 in the direction of arrow a, as shown in FIG. The two shutters 34 are moved in the direction of arrow b. At this time, a portion of the first shutter 32, the light shielding sheet 33, and the second shutter 34 enter the optical path, thereby blocking the light in the optical path corresponding to the portion where toner should be prevented from adhering. If the first shutter 32 is further moved in the direction of arrow a and the second shutter 34 is further moved in the direction of arrow b, the portion of the image corresponding to the optical path blocked by the first shutter 32, the light-shielding sheet 33, and the second shutter 34 is no longer projected onto the photosensitive drum 21, and a copy of a portion of the image, that is, an edited copy, can be obtained, and it can be seen on the screen 20 which part will be copied.

When performing the above operations, the light shielding sheet 33 can freely move in and out between the substrate 31 and the fourth reflecting mirror while being curved, as shown in FIGS. 4 and 5. In this way, if only a plate-shaped material is used as a light shielding member,
Even if it is impossible to attach the light shielding device to the main body of the image forming apparatus, it is possible to attach the light shielding device to the main body of the image forming apparatus by using a sheet-like light shielding member.

FIG. 7 shows a second embodiment of the present invention. In order to simplify the explanation, the same parts as in the first embodiment are given the same reference numerals, and only the different points will be explained. In this embodiment, a winding mechanism 41 for winding up and storing the light shielding sheet 33 is provided below the fourth reflecting mirror 14. The other configurations are the same as those of the first embodiment described above. In this embodiment with the above configuration, the light shielding sheet 33 is attached to the substrate 31.
When escaping through between the shading sheet 3 and the fourth reflecting mirror 14,
It is possible to avoid the situation where there is an obstacle such as a part near the place where the light-shielding sheet 33 escapes, and the light-shielding sheet 33 comes into contact with this obstacle, causing an inconvenience, and it can be made more compact.

FIG. 8 shows a third embodiment of the present invention. In the second embodiment, the light-shielding sheet 33 was rolled up, but in this embodiment, the light-shielding sheet 33 is folded into a bellows shape between the first shutter 32 and the lower end of the fourth reflecting mirror 14, which saves money. This is an attempt to create a space. The other configurations are the same as those of the first embodiment described above. In this embodiment, if necessary, it is also possible to restrict the storage location of the light-shielding sheet 33 using a guide plate (not shown) or the like.

[
0016

Effects of the Invention As explained above, the present invention uses a plate-shaped light shielding member movable on a plane perpendicular or nearly perpendicular to the optical path on the optical path common to the reader and printer. The light shielding device can be attached with a small space in the optical axis direction, and by using a sheet-like light shielding member in combination, the light shielding device can be attached in a narrower space in the plane direction than before. This allows the entire device to be miniaturized, has an extremely simple structure, and can be manufactured at low cost.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a light shielding device portion in a reader printer as an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of the reader printer when it is a reader.

FIG. 3 is a schematic configuration diagram at the time of printing.

FIG. 4 is an explanatory diagram of the operation of the light shielding device.

FIG. 5 is another explanatory diagram of the operation of the light shielding device.

FIG. 6 is a plan view of a microfilm used in a reader printer.

FIG. 7 is a side view of a light shielding device portion in a reader printer according to a second embodiment of the present invention.

FIG. 8 is a side view of a light shielding device portion in a reader printer according to a third embodiment of the present invention.

[Explanation of symbols]

F Microfilm 1 Lamp 5 Projection lens 11 First reflecting mirror 12 Second reflecting mirror 13 Third reflecting mirror 14 Fourth reflecting mirror 15 Fifth reflecting mirror 16 Sixth reflecting mirror 20 Screen 21 Photosensitive drum 31 Substrate 32 First shutter ( Light shielding member) 33 Light shielding sheet 34 Second shutter (light shielding member) 35 Connecting plate 36 Rotating shaft 37 Operation knob 41 Winding mechanism

Claims (1)

[Claims] 1. A reader state in which an image on an image support is projected onto a screen by a projection lens for observation;
In an image forming device that is switched to a printer state in which the image is projected onto an exposure unit to obtain an image, the image forming device is installed perpendicularly or nearly perpendicularly to the optical path downstream of the projection lens and on the optical path that is common during reading and printing. An image forming apparatus characterized by disposing a plate-like light-shielding member and a sheet-like light-shielding member that are movable on a surface.