JPS63787B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic method that allows editing.

Conventionally, the main purpose of electrophotographic apparatuses has been to faithfully reproduce the information contained in an original painting, and great efforts have been made to obtain reproductions that are closer to the original. As a result, it is now possible to obtain reproductions of very good quality, and in particular, with black-and-white copying machines, it is now possible to obtain reproductions of almost the same quality depending on the original.

On the other hand, in practice, there are many cases where it is desired to erase unnecessary information in the original image or insert other information into the erased portion. For this reason, in the past, the original image was once copied, cut and pasted to create a new original image, and this was further copied to obtain the necessary information. Therefore, modern demands on copying machines include not only being able to faithfully reproduce the original picture, but also making it possible to perform such editing.

Generally, when editing a manuscript using a machine, characters are encoded using a typewriter, image information is broken down into bit patterns using a scanner, this is edited using a computer, and the output is sent to a printer or X-ray machine.
Images were played back by inputting them into a Y-Protector, etc. However, this method requires a typewriter or a high-speed scanner, and also requires an electronic computer for processing, which has drawbacks such as the time it takes to create a program.

Editing of information according to the present invention is performed by several devices incorporated into the electrophotographic device.

The electrophotographic method according to the present invention includes a two-color mode in which a part of a document to be copied is reproduced in a color different from that of the document, and a part of the document whose density is different from other parts even if the color is the same as that of the document. You can edit the density modulation mode.

According to the electrophotographic method of the present invention, in addition to normal copying, it is also possible to edit image information, so it is possible to create copies that are faithful to the original as well as copies that are different from the original. This will help streamline the process.

Accordingly, it is an object of the present invention to provide an improved electrophotographic method.

A further object of the present invention is to provide an electrophotographic method with an editing function.

Hereinafter, the present invention will be described with reference to the attached drawings.

FIG. 1 is a diagram schematically showing an example of an electrophotographic apparatus using the electrophotographic method of the present invention. Inside the apparatus main body 1, a photosensitive drum 2 and a transfer drum 3 having the same diameter are rotatably provided in contact with each other. The photosensitive drum 2 rotates counterclockwise, and the transfer drum 3 rotates clockwise. Around the photoreceptor drum 2, along the rotation direction,
Charging corona discharger 4, charge erasing device 5, first developing device 6, second developing device 7, separating corona discharger 8, cleaning device 9, static eliminating corona discharger 1
0 and quenching lamps 11 are respectively arranged.

A document table 12 having a transparent contact glass is arranged at the top of the apparatus main body 1, and a document 13 is placed thereon. Below the document table 12, there are an illumination lamp 14, a first reflection mirror 15, a second reflection mirror 16, an in-mirror lens 17, a third reflection mirror 18, and a color filter unit 19, each having a predetermined optical positional relationship. It is arranged as follows. The illumination lamp 14 and the first reflection mirror 15 move together from the position shown by the solid line to the position shown by the dashed line to scan the original 13 on the original platen 12.
At this time, the second reflecting mirror 16 also moves in the same direction at half the speed of the first reflecting mirror 15. The filter unit 19 includes a color separation filter and
An ND filter is set, and only the ND filter is used for normal black and white images. The above-mentioned illumination lamp 14 and first reflection mirror 15
The lamp unit 61 is constructed as a unit as shown in FIG. 2, and the entire lamp unit 61 slides while being supported by a guide rod 62, and includes a lamp 63 corresponding to the illumination lamp 14 shown in FIG. , reflectors 64, 65, and a reflecting mirror 66 corresponding to the first reflecting mirror 15 in FIG. 1 are arranged with a predetermined optical positional relationship.

The lamp unit 61 is structured to be synchronized with the photosensitive drum 2, and specifically has a drive structure shown in FIG. 3.

That is, a sprocket wheel 74 is fixed to the shaft 71a of a motor 71 for driving the lamp unit 61, and a chain 76 is passed between the sprocket wheel 74 and the sprocket wheel 75 fixed to the shaft 2a of the drum. There is. A pulley 77 is fixed to the shaft 2a of the drum, and a wire 80 is stretched between this pulley 77 and pulleys 78 and 79 provided at both ends of the contact glass 12. Lamp unit 61 is fixed to a wire section between pulleys 78 and 79.

Another sprocket wheel (not shown) is fixed to the shaft 2a of the photosensitive drum 2, and this sprocket wheel receives power and rotates the photosensitive drum 2 in a clockwise direction. At the same time, the sprocket wheel 77 also rotates, and the lamp unit 61 moves in the direction of arrow A in synchronization with the photosensitive drum.

When the photosensitive drum 2 rotates counterclockwise, its surface is uniformly charged by the charging corona discharger 4. When an optical image of the document 13 is irradiated onto the surface by an optical system, charges are dissipated in accordance with the optical image, and an electrostatic latent image is formed there. The charge erasing device 5 is for erasing the charge on a predetermined portion of the surface of the photoreceptor based on the setting of a specified range on the document table, which will be described in detail later, so that a latent image is not created on that portion. , not used in normal copy mode. The electrostatic latent image on the surface of the photoreceptor is visualized by a developing device. First developing device 6
contains developer of any color other than black, and is used in two-color mode. The second developing device 7 contains a black developer, and normally only this developing device is used. Development is performed by electrostatically adsorbing colored fine particles called toner in the developer to the electrostatic latent image. After development, the surface of the photoreceptor is subjected to discharge from a separating corona discharger 8, and the electric charge on the toner is removed.

The transfer drum 3 is provided with a transfer paper holding device 20, which holds the transfer paper 23 fed by the paper feed roller 22 on the circumferential surface of the transfer drum 3 by synchronizing this with the registration roller 21. do.
The rotations of the photoconductor drum 2 and transfer drum 3 are synchronized, and the leading edge of the image on the photoconductor drum and the leading edge of the transfer paper on the transfer drum advance in unison, overlap at the point of contact between the two, and the leading edge of the image on the photoconductor toner image is transferred onto the transfer paper. Subsequently, the transfer paper is separated from the transfer drum 3 by the separation claw 24, and transferred to the fixing device 25.
and is discharged onto the tray 26. On the other hand, toner remaining on the surface of the photosensitive drum 2 is removed by a cleaning device 9, and charge remaining on the surface and inside of the photosensitive drum 2 is removed by a static eliminating corona discharger 10 and a quenching lamp 11. Ru.

In normal copy mode, the original placed on the document table is scanned during one rotation of the photoreceptor drum and transfer drum, and the electrostatic latent image formed on the photoreceptor is processed into a visible image. and completes the copying cycle by transferring the visible image to transfer paper,
When copying in two-color mode, the photoreceptor drum and transfer drum complete one copy cycle in two revolutions.

The copying machine shown in FIG. 1 incorporates a special device for performing an editing mode. next,
These devices will be explained.

First, the line designation device will be explained with reference to FIG. This device 30 is a device for setting a specified range such as a line or range to be changed in the scanning direction of a document for editing, and is a device for setting a specified range such as a line or a range to be changed in the scanning direction of the document. It is provided on one side in the vertical direction, that is, in the longitudinal direction. A guide rod 31 is fixed to the main body of the copying machine on the side surface of the contact glass 12, and a first marker 32 and a second marker 33 are slidably attached to the rod 31 so as not to rotate. A reference marker 34 is non-slidably attached in alignment with the tip of the contact glass, that is, the scanning start position. Sensors 35, 36, and 37 are attached to each marker so as to protrude outward in the lateral direction. Each sensor is adapted to be located on the upper belt of a scale belt 40, which has a scale of pitch n and extends between two rollers 38,39. When the sensor is a photo coupler, the scale belt 40 is a transparent film, and the light emitting part and the light receiving part of the photo coupler sandwich this film. Also, the scale belt 40
can be made from magnetic tape, in which case the sensor becomes a magnetic head. scale belt 40,
A motor 41 connected to one roller 38 rotates it in the direction of the arrow.

The first marker 32 and the second marker 33 are manually positioned, and the width between them, in other words, the width of the document in the scanning direction becomes the specified range of the document to be changed. The scale belt 40 has a reference point 42
is provided, and when the belt 40 is rotated in the direction of the arrow by the motor 41, the reference sensor 37 first detects the reference point 42, a counter (not shown) connected to this sensor is cleared, and the belt passes under it. Start counting the number of tick marks. The number of counts when the reference point 42 passes under the first sensor 36 is stored in the computer, and the number of counts when the reference point 42 passes under the second sensor 35 is similarly stored in the computer. Ru. As a result, the distance of each marker from the end of the contact glass, that is, from the scanning start position, is stored, and several characteristic processes are performed based on this.

Note that in the specified range described above, for example, when specifying a line using a marker, instead of specifying a line to be changed, it is also possible to specify a line to be left unchanged. Also, if there are lines that should or should not be changed intermittently, you can specify them at once using many markers and have the computer memorize them.

If the exposure scanning system is of the type in which the lamp unit is stationary and the document table moves, a scale is provided directly on the side of the contact glass, and the distance of each marker from the scanning start position can be determined by moving the document table. It is preferable to detect this and store it in the computer.

Next, the charge erasing device will be explained with reference to FIG. This is a type of charge control device for partially charging the surface of the photoreceptor, and is a device for preventing the formation of a latent image on unnecessary portions of the photoreceptor without charging those portions. There are two types of devices: one that partially charges the photoreceptor and the other that partially erases the charge on the surface of the photoreceptor. In the former case, the input to the charging corona discharger is opened and closed as appropriate, and a switching plate is provided on the front surface of the corona discharger, and this is opened and closed as appropriate to perform partial charging. In the latter case, a white mask means is provided on the document table, and the unnecessary portion of the document to be deleted is appropriately inserted and exposed to dissipate the charge in this portion, or a slit-type white exposure means is used for normal exposure. It is provided separately from the means, and the charges are erased by operating it as appropriate. The charge erasing device 5 shown in FIG. 5 is this last example. Since the deleted portion of the document may be very narrow, the exposure operates at high speed. A narrow slit exposure with a width of about 0.5 to 3 mm must be used.

In FIG. 5, reference numeral 51 designates a lamp housing in which a lamp 53 provided with a reflector 52 is accommodated. lamp housing 51
is an elongated casing that is slightly longer than this width along the width direction of the photoreceptor drum, and its lower part is constricted and continues into another narrower casing portion 51a. A biconvex cylindrical lens 54 is fitted into the boundary between the upper casing and the lower casing within the lamp housing. A horizontal slit 51b and a vertical slit 51c connecting the centers of the lamp 53 and the lens 54 are provided at the center of the lower housing. Partition plates 51d and 51e are provided above and below the horizontal slit 51b to allow a vertical slit with a width of 0.5 to 3 mm. A shielding plate 55 having a slit having the same width as the vertical slits provided in both partition plates is inserted between the horizontal slits. On one side of the shielding plate 55,
An armature 56 is fixed, and a tension coil spring 57 is fixed to the other side. As a result, the shielding plate 55 is always pulled in the direction of the arrow, so that the slits in the shielding plate 55 do not match the vertical slits provided in the partition plates 51d and 51e. Electromagnet 5 facing armature 56
8 is provided, and when this electromagnet is energized, the armature 56 is attracted to it, and the shielding plate 55
The slits of the two partition plates 51d and 51e match. Therefore, while the electromagnet is energized, slit exposure with white light is performed,
The charge on the photoreceptor surface is erased.

The charge erasing device, that is, the charge control device described above, is
Based on the specified range setting on the document by the line specifying device, the area corresponding to the specified range on the photosensitive drum 2 (hereinafter referred to as the first area) is made uncharged, and as a result, the first area Other areas (hereinafter referred to as
In the case of forming an electrostatic latent image of the document image (hereinafter referred to as the "first step") in the second region (hereinafter referred to as the "first step"), in the case of forming an electrostatic latent image of the document image on the The case where the second area is made uncharged and an electrostatic latent image of the document image is formed in the first area (hereinafter referred to as the second step) is selected.

Next, referring to FIG. 6, the photoreceptor position detection device 8
1 will be explained.

This device is necessary for erasing the charge on the photoreceptor area for the document area specified by the line specifying device.

A scale disk 82 having a scale of pitch n is fixed to the shaft 2a of the photoreceptor drum 2, and when the photoreceptor drum 2 is normally at a predetermined rotation start position, that is, a scanning start position, the scale circle is Board 8
The two reference points 83 are located on a sensor 84 provided on the main body of the copying machine. Therefore, the contents of this sensor 84 and the counter connected thereto are counted in advance by the line specifying device, and the charge erasing device is mechanically set at an angle and corrected by converting the number of pulses, etc. If the contents of the counter and the sequence timing match the data stored in the memory, the electric charge on the designated portion of the photoreceptor can be erased.

Of course, if the photoreceptor is plate-shaped, the scale plate is not a circular plate but a linear plate.

Next, the developing device 91 will be explained with reference to FIG.

The developing device used in this invention is equipped with two developing devices for editing in two-color mode. Even with two developing devices, three-color development can be performed by mixing colors. Furthermore, if two or more developing devices are provided, it is also possible to develop two or more colors. This invention includes such modifications.

When developing two colors using two developing devices, it is necessary to prevent the other color developing devices from operating while one color is being developed. Otherwise, two developing devices will work and the developed image will have mixed colors. As a method of not operating the developing device, the method used in the present invention is to use a magnet in a non-magnetic sleeve as an electromagnet in a magnetic brush developing device, and to cut off power to the magnet when the developing device is not in operation. In FIG. 7, a developing device 91 includes a toner replenishing device 93, an impeller 94, a conveying roller 95, a developing roller 96, and a scraping plate 9 in a developing container 92.
7 are arranged at predetermined positions, respectively. The toner replenishing device 93 is a device for appropriately replenishing new toner into the developing container 92, and the toner 98 therein is thrown into the developing container by the rotation of the supplying arm 99. The impeller 94 is connected to the developer container 9
The developer 100 in the developer 100 is stirred and fluidized, and the toner and magnetic carrier constituting the developer 100 are each frictionally charged to a predetermined polarity.
The conveyance roller 95 consists of a non-magnetic sleeve 101 that rotates counterclockwise, and permanent magnets 102 and 103 that are statically housed inside the sleeve 101.
It has the role of attracting the developer 100 to the surface of the non-magnetic sleeve 101 and transporting it upward. The developing roller 96 is provided close to the conveying roller 95 and includes a non-magnetic sleeve 104 that rotates in a counterclockwise direction, and electromagnets 105, 106, and 107 that are statically housed inside the non-magnetic sleeve 104. Electromagnet 1
05, 106, 107 are switch 10 respectively
It is connected to the power supply 111 via 8, 109, and 110. When activated, switches 108, 10
9 and 110 are all closed, which energizes each electromagnet and transfers the developer on the conveying roller 95 onto the developing roller 96. The transferred developer is conveyed upward on the developing roller by the rotation of the non-magnetic sleeve 104, and on the way, the thickness of the developer layer is regulated by the doctor 112, and comes into contact with the photoreceptor drum 2. The electrostatic latent image on the photoreceptor drum is then visualized. Subsequently, the developer on the developing roller is removed from the developing roller by a scraping plate 97 and collected into the developing container 92 . Development is carried out by the toner in the developer being attracted to the electrostatic latent image, so the recovered developer has a lower toner concentration and an amount of new toner equivalent to the amount consumed by development. is replenished into the developing container from the toner replenishing device 93. When not developing, switches connected to each electromagnet are opened in the order of switches 108, 109, and 110 to stop new conveyance of the developer and remove the developer remaining on the developing roller with a scraping plate. Scrape everything off with 97.

Next, referring to FIG. 8, the control system when performing the edit mode will be explained.

When the marker of the line designation device is set and detected by the sensor, this is input to the counter 121, and the position from the reference is counted. The output of the counter 121 is input to the second computer 123 through the input/output device 122. The second computer 123 works as a calculator, and the counter 121
Based on the data sent from
126. The ROM 127 stores a program for performing this calculation. on the other hand,
The output from the sensor of the photoreceptor detection device is input to a counter 128, whereby the position of the photoreceptor is detected, and the result is sent to the first computer 130 through an input/output device 129. The first computer 130 works as a sequencer,
A sequence order is assembled from the data stored in the RAM 126 and the editing mode designated by the operator, and the sequence is executed through the input/output device 131 based on the count result from the counter 128. The ROM 132 stores programs for performing sequences.

Next, referring to FIG. 9, the actual editing mode will be explained. For convenience of explanation, the output from the scale belt in the line specifying device is divided into six equal parts of the length in the scanning direction of the contact glass on which the original is placed, and the scale on the scale disc in the photoreceptor detection device is The circumference of the photoreceptor drum is divided into 6 equal parts, and the number of counts on each scale is n0, n1, n2, n3, n4,
Let it be n5. The length of the contact glass in the scanning direction is equal to the circumferential length of the photoreceptor drum. The original to be used should be the size of the entire surface of the contact glass, and as shown in Figure 9, it should be A, B, C,
It has five rows D and E, and counting is performed between each row. Further, the angle between the position of the charge erasing device and the exposure position on the photosensitive drum is one scale.

The two-color mode is performed through the following steps. This two-color mode is a format in which a specific line of a document is copied in a different color from other lines. Therefore, two copying cycles are required, with each color being developed in each cycle. As an example of the two-color mode, A, B, D, and E of the original
A case will be described in which the rows are developed in black and the C rows are developed in red. First, specify the two-color mode using the control panel, and as shown in FIG.
Set marker 33 between rows C and D. Marker designation in this mode involves erasing the charge during the first copy cycle in the marker designated area, that is, the above-mentioned first area, and erasing the charge during the second copy cycle in the area other than the marker designation, that is, the above-mentioned first area. The program is designed to require operations in the second area. Therefore, in the first copying cycle, the area other than the C line, which is the marker designated area corresponding to the first area, is developed black, and this is once transferred onto the transfer paper. The transfer paper enters the second copying cycle while being held on the transfer drum, and after the photoconductor is charged, the charges in the area other than the C row, which is other than the marker designated area corresponding to the second area on the photoconductor, are erased. As shown in FIG. 10, C
A latent image of only rows is formed. This is developed into red using another developing device, and when this is transferred to the transfer paper on which the black image has already been transferred, A, B, D, E
A copy is obtained in which the rows are black and the C row is red. In this way, the image forming conditions, ie, the development conditions in this case, can be changed so that the image becomes a different color with respect to the image obtained by the previous black development.
This order may be reversed to develop and transfer the C row first.

Two-color mode is used to make a particular row stand out by making it a different color than the other rows. Therefore, in order to make a particular line stand out, even if the lines are of the same color, it is only necessary that the line be expressed in a particularly dark color. This editing mode is a density modulation mode, and in order to do this, when forming the latent image of row C in the second copying cycle, the photoreceptor charging potential must be set higher than that in the first copying cycle. Then, a latent image with a high potential can be formed. If this is done, more toner will adhere, so that row will be developed darker than the others even if they are of the same color.

The two-color mode can be converted into a multi-color mode by providing the necessary programs and a large number of developing devices.

In the above embodiment, the light source of the charge erasing device is not a single long tube, but small light emitting elements are arranged in a row, and in addition to changing the row units, shielding plates are provided on both sides. , it is also possible to delete a specific part in one line.

Furthermore, various modifications can be made within the spirit of the invention and are included within the scope of the claims of the invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of an electrophotographic apparatus used in the electrophotographic method according to the present invention, FIG. 2 is a sectional view of an exposure scanning system in the apparatus shown in FIG. 1, and FIG. 1 is a perspective view showing the drive structure of the scanning system in the apparatus shown in FIG. FIG. 6 is a schematic diagram showing a charge erasing device used in the charging step in the method, FIG. 6 is a schematic diagram showing a photoconductor position detection device used in the device of the present invention, and FIG. FIG. 8 is a schematic diagram showing a developing device; FIG. 8 is a block diagram showing a control system for performing the editing mode in the present invention; FIG. 9 is a diagram showing a manuscript used when explaining each editing mode;
FIG. 0 is a diagram for explaining the two-color mode. 5... Charge erasing device, 30... Line designation device, 3
2, 33...Marker, 81...Photoconductor position detection device, 91...Developing device.

Claims (1)

[Scope of Claims] 1. A document to be copied is placed on a document table, the document is scanned to form an electrostatic latent image on a photoreceptor, and this electrostatic latent image is visualized, and then In an electrophotographic method for obtaining a copy by transferring the visible image onto a transfer paper, a designated range setting step of setting a designated range of a desired width in the scanning direction of the document table; a first step of rendering a first area on the photoconductor corresponding to the specified range uncharged and forming an electrostatic latent image of the document image in a second area other than the first area; Based on the specified range setting means, the second
A charging step is carried out by switching between leaving the region in an uncharged state and forming an electrostatic latent image of the document image in the specified range in the first region; a developing step of visualizing the electrostatic latent image in the second region formed on the photoreceptor in the second step; A developing step of visualizing the visible image of the region with a developer of a different image density or a different color, and a visible image of the second region obtained based on the first step and the second step. An electrophotographic method comprising: a transfer step of transferring a visible image of the first region obtained based on the first region onto a portion of a photoreceptor corresponding to each of the above-mentioned regions on the same transfer paper.