JPH02120751A - Color separation electrophotographic engraving machine - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a color separation electrophotographic engraving machine capable of color printing, and more specifically to a color separation electrophotographic engraving machine equipped with a color separation filter and a contact screen for halftone dotting. Regarding machines.

[Prior Art] Conventionally, as a method of obtaining printed matter from monochrome originals such as line drawings and characters, plate making and printing by direct plate making using an electrophotographic method, which is easy to operate and aims to improve work efficiency, has been widely used.

However, when plate-making and printing are performed directly from an original having continuous gradation, such as a color photographic original, the resulting printed matter has poor midtone expression and strong contrast.

Therefore, as a first method, originals with continuous gradations such as color photographic originals are not directly plate-made by direct plate-making, but are first processed using a silver-halide plate-making camera or the like to produce blue-purple (B). , green (G).

Color separation is performed using each red (R) filter, and then a contact screen is placed in close contact with photographic paper to perform net separation.

This is combined and edited to match the manuscript such as line drawings and text to the final print layout, and a manuscript is created for each color.
Printing plates for each color are created using direct plate making.

Furthermore, the offset printing machine produces yellow.

Magenta, cyan, and black inks are printed over each other to reproduce the colors of a color original.

On the other hand, as a second method, an "electrophotographic network decomposition device" (Jikkosho 4l- 7905).

This is an apparatus in which a screen is placed on the exposure position on a movable exposure table when the screen is to be separated, and only the screen is removed when the screen is not to be separated.

[Problem to be solved by the invention]

In the first conventional method, each color is combined and edited according to the final printed layout, which not only takes a long time but also complicates the process.
There are some points in which good printed matter cannot be obtained.

The second method, the halftone decomposition device, separates the halftone dots from a compositely edited original such as line drawings, text, and photographic originals.The photographic original is decomposed into continuous tone dots.
Characters also had the disadvantage that halftone dots were formed, and each type had to be made into plates separately. In addition, its use has decreased in recent years due to the labor involved and cost.

In addition, in order to perform color printing, it is necessary to use color separation filters and contact screens for halftone dots, but when using contact screens for halftones with conventional electrophotographic engraving machines, there is a problem that discharge damage occurs. There was a point. In other words, the contact screen was originally intended for use with silver halide film and photographic paper, and when used in an electrophotographic engraving machine, the contact screen was used to charge the photoreceptor surface. There is a problem in that discharge destruction occurs when the photoreceptor comes into close contact with or peels off, which has a fatal effect on the image, making it impossible to create a color printing plate directly from a color original such as a photograph or illustration. Regarding this point, Japanese Patent Application No. 63-179154, which is an earlier application by the applicant of the present application, discloses that a contact screen is continuously brought into close contact with the surface of a photoreceptor by a roller.
Alternatively, a proposal has been made to peel it off, thereby solving the problem of discharge breakdown.

Also, when shaded by contact screen,
There is a problem in that the entire surface area of the photoreceptor is covered with halftone dots, making it impossible to obtain clear line drawings, characters, etc.

The purpose of the present invention is to solve the above problems, provide excellent operability,
Another object of the present invention is to provide a color separation electrophotographic plate making machine that can produce excellent color printing plates.

[Means to solve the problem]

The color separation electrophotographic engraving machine according to the present invention includes an original placing table, a first exposure means provided in relation to the original placing table, and forming an image by receiving light from the first exposing means. a photoconductor support means formed at a predetermined position for the purpose of the present invention; a photoconductor supply means for supplying the photoconductor to the photoconductor support means along a predetermined supply path; the document placement table; and the photoconductor support means. a color separation filter provided between the photoreceptor supporting means, a meshing contact screen that is continuously adhered to or peeled off from the photoreceptor on the photoreceptor support means by a movable roller; a charging means that charges the photoreceptor; and at least a partial region of the photoreceptor that is located between the charging means and the photoreceptor supporting means in the middle of the predetermined supply path and that is charged by the charging means. a second exposure means for
The apparatus is characterized by comprising a discharge means for discharging the photoreceptor exposed by the exposure means from the photoreceptor support means to a discharge port.

[Function] In the above configuration, the photoreceptor supplied from the photoreceptor supply means is charged by the charging means and supplied to the photoreceptor support means,
An image of the color original on the original table is formed by exposing the color original from the first exposure means through the filter and the contact screen. Here, the contact screen is continuously brought into close contact with or peeled off from the photoreceptor by a movable roller, thereby preventing charge discharge damage. The photoreceptor exposed on the photoreceptor support means is discharged after passing through a developing device and a fixing device, which are provided as necessary.

The second exposure means can be used selectively, and when the second exposure means is not used, the above operation is carried out,
A color original image is formed on the entire surface of the photoreceptor. When the second exposure means is used, at least a part of the photoreceptor is exposed before the photoreceptor charged by the charging means reaches the photoreceptor support means. Thereafter, this photoreceptor is supplied to a photoreceptor support means and exposed by the first exposure means. At this time, since the charges in the part of the area exposed by the second n-light means have been discharged, no image is formed in the same part of the area when exposed by the first exposure means. Therefore, this part of the area does not become a shaded image, and can be used for purposes where shading is not desired.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows the external appearance of a color separation electrophotographic plate making machine according to the present invention, and FIG. 1 is a diagram showing the internal structure of the color separation electrophotographic plate making machine shown in FIG.

Referring to FIG. 2, the color separation electrophotographic engraving machine has an outer case 10, and an operation panel 12 is provided in front of the outer case 10. Details of the operation panel 12 are shown in FIG. 3, and various operation keys are arranged. Above the operation panel 12 is a display 14, and further above that is an IC card insertion slot 18 into which an IC card 16 is inserted. A contact screen cartridge 20 can be inserted next to the operation panel 12 in a generally vertical arrangement. Further, on the left side surface of the outer case 10, there are first and second discharge ports 22 , 24 , and a cut photoreceptor supply port 26 .

Referring to FIG. 1, in the upper left inside of the outer case 10, there is a first plate comprising a document placing table 2B and an exposure light source 30a.
Exposure means 30 is arranged. At the upper right side, there is a photoreceptor support means 32 for receiving light from the first exposure means 30 and forming an image. The flash lamp 31 is selected and used during halftone imaging. The optical system is the original table 28
It consists of a reflective mirror 34 above, a lens 36, a color separation filter 38, and a contact screen 40 for halftone contact that is adhered to or peeled off from the photoreceptor on the photoreceptor support means 32. Contact screen 40 is housed in contact screen cartridge 20.

At the lower right inside of the outer case 10, there are two photoreceptor rolls 42 and 44, and a cutter device 42a.

44a is provided in association with each photoreceptor roll 42,44. The outlets of the cutter devices 42a, 44a are commonly connected to a pair of pinch rollers 46, for example.

Therefore, a sheet-like photoreceptor of a predetermined length is taken out from either of the photoreceptor rolls 42 and 44, and the photoreceptor supporting means 32 is moved by the pinch roller 46 and a group of pinch rollers arranged in a predetermined first supply path beyond the pinch roller 46. can be supplied to A suitable guide plate or the like is provided in cooperation with the pinch roller group in order to transport the photoreceptor without deviating from the supply path. Further, a sheet-like photoreceptor can be inserted and supplied from the above-mentioned cut photoreceptor supply port 26 . In this case as well, a pair of pinch rollers 48 and a group of pinch rollers arranged in a predetermined second supply path are disposed at the tip of the feed port 26 of the cut photoreceptor. The first and second supply paths meet at pinch roller 50 and then proceed to photoreceptor support means 32.

Pinch rollers 50 are provided at the convergence portion of the first and second supply paths.
Charging devices 52 and 54 are provided on the upstream side of the photoreceptors, respectively, so that the photoreceptor can be charged, for example, negatively. The confluence pinch roller 50 can be driven independently of the pinch rollers upstream thereof. In association with this pinch roller 50, a second exposure means 56 is arranged.

The photoreceptor exposed by the first exposure means 30 in the photoreceptor support means 32 is discharged from the photoreceptor support means 32 to the first and second discharge ports 22 and 24. The discharge path of the photoreceptor is constituted by a pinch roller 58 and the like, and follows a path different from the supply path, and there is a developing section 60 for the photoreceptor on the way.
, a fixing section 62, and an etching section 64 are provided. In the embodiment, the photoreceptor that passes through the etching section 64 is discharged to the first outlet 22, and the photoreceptor that does not pass through the etching section 64 is discharged to the second outlet 24. These developing section 60, fixing section 62, etching section 6
4 can be used as one well known in the electrophotographic technology, so a detailed explanation will be omitted. Each of the above components will be explained in more detail later.

Pinch rollers 46, 50, etc. in the supply path1. Several motors (electric motors) are provided to drive the pinch rollers 58 and the like in the discharge path, but such motors are omitted in FIG. 1.

Further, in order to control such a motor, a large number of path sensors (not shown) are provided along the photoconductor supply path and discharge path. For example, if the photoreceptor is cutter device 4
2a, 44a, and pinch rollers 46, 50, 5
A path sensor is provided that detects passing through the 8th grade.

The color separation electrophotographic engraving machine having the above configuration is operated by operating various keys on the operation panel 12 and by outputting from the path sensor. At the same time, the IC card inserted into the IC card insertion slot 18 (Fig. 2)
The operation of the second exposure means 56 is mainly controlled according to the contents stored in the C card 16. The stored contents of the IC card 16 are inputted, for example, by a trimming area input device 66 as shown in FIG. The trimming area input device 66 includes an insertion slot 68 for the IC card 16, a numeric keypad 70, and a display 72. Details of the numeric keypad 70 are shown in FIG.

Furthermore, the trimming area input device 66 is connected to an image scanner 74 shown in FIG.
4 is stored in the tC card 16. In this way, ICs with different memory contents for each document can be used.
Create a card 16 and use the IC card insertion slot 18 (Figure 2)
Insert and use.

Next, an example of creating the IC card 16 will be described with reference to FIGS. 6 to 8. FIG. 8 shows means for preparing a manuscript. (A) shows a document mount 76, in which an original 11i77 is pasted in a document pasting area 76a indicated by a dashed line. The position X of the original pasting area 76a provides a reference position corresponding to the corner of the original 77, and the original pasting area 7
Two holes 78 and 79 are provided at the outer edge of 6a. These holes are 32 in the upward direction from the reference position X and S in the horizontal direction.

and St+L position. One hole 79 is long. (B) shows a transparent sheet 80 to be placed on the original mount 76, with holes 78a and 79 corresponding to holes 78 and 79.
9a is provided. (C) shows a pinper 82 for fixing the stacked document mount 76 and transparent sheet 80, and is provided with two holes 78 and 79 and corresponding pins 82a and 82b.

7th. The figure shows the use of markers 84 to make marks 86a, 86b, 86c in partial areas of transparent sheet 80 on top of document base 76 stacked in this manner. FIG. 6 shows a mark 86a.

The transparent sheet 80 with markings 86b and 86c attached thereto is shown placed upside down on the image scanner 74. The image scanner 74 also has pins 82a and 8 of the pinper 82.
2b are provided with pins 74a and 74b. Therefore, the image scanner 74 can optically scan the marks 86a, 86b, 86c using the reference position X as a reference and write them on the IC card 16. Then, this IC card 16 is removed from the trimming area input device 68 and inserted into the IC card insertion slot 18 of the color separation electrophotographic engraving machine.

FIG. 9 is a detailed view of the document placement table 28 shown in FIG. 1. The original table 28 is made up of an outer frame 28a, a flexible table 28b that supports the original holder 76, and a transparent glass 28c that can be opened and closed, and has holes 78 and 79 for fixing the original holder 76.
There are corresponding bins 28d and 28e. Note that since the transparent sheet 80 is removed, no mark is placed on the document 77, but it is shown with a two-dot chain line for reference.

FIG. 10 is a detailed diagram of the color separation filter 38 of FIG. The color separation filter 38 consists of a filter mounting plate 38a and a support shaft 38b attached to the center of the filter mounting plate 38a, and a gear 38c is fixed to the support shaft 38b. Further, a gear 38d connected to the pulse motor 38i meshes with the gear 38c, thereby making it possible to rotate the filter mounting plate 38a. The filter mounting plate 38a is coated with a well-known blue-purple (B
), green (G).

Three types of red (R) filters 38e, 38f, 38g,
A window 38h is provided for when no color separation is to be performed, and either of these can be driven to a rotational position that aligns with the lens 36.

FIG. 11 is a detailed view of the photoreceptor support means 32 and contact screen 40 contained in the contact screen cartridge 20 of FIG. Photoreceptor support means 3
2 consists of a vacuum box 32b that receives suction from a vacuum pump 32a;
The photoreceptor can be absorbed and supported by numerous small holes provided on the front surface of the photoreceptor. Further, the photoreceptor supporting means 32 includes a gripping claw 32f fixed to an endless belt 32e driven by a motor 32c and a pulley 32d. The gripper claw 32f is normally in a lower standby position as shown in FIG. The receiver is lifted to an upper support position, where vacuum is applied to the vacuum box 32b to support the photoreceptor on the front surface of the vacuum box 32b. Further, when discharging, the vacuum is turned off, the gripper claw 32f is lowered to the lower standby position, and the pinch roller 58 for discharging is activated.

As shown in FIGS. 1, 11, and 12, the contact screen cartridge 20 is mounted in a frame-shaped shading holder 88 disposed inside the color separation electrophotographic engraving machine.
It is designed to be accommodated in That is, the frame-shaped meshing holder 88 is provided with guides 88a and 88b for guiding the upper and lower surfaces of the contact screen cartridge 20, so that the contact screen cartridge 20 can be attached and removed in a drawer-like manner (FIG. 12). The mesh holder 88 is rotatably attached to a support shaft 90, rotated relative to the photoreceptor support means 32 by a drive means (not shown), and held at a predetermined position relative to the vacuum box 32b as shown in FIG. It has a non-operating position forming an angle of , and an operating position directly facing the vacuum box 32b as shown in FIG.

Further, one end side of the support shaft 90 is coupled to the output shaft of a motor 92, and a pulley 94 is attached to the support shaft 90. A slide guide 96 extending in the vertical direction is attached to the side surface of the meshing holder 88, and a slider 98 is attached so as to be slidable along the slide guide 96. Similarly, a slide guide 100 extending vertically also extends on the side surface of the contact screen cartridge 20.
is attached, and the slider 102 is attached to the slide guide 10.
0. The slider 98 is provided with a connecting means 104, and when the contact screen cartridge 20 is accommodated in the shading holder 88, the slider 9 and the slider 102 are connected and can be slid at the same time. The slider 98 is connected to the pulley 94 and the pulley 94a.
The slider 102 of the contact screen cartridge 20 is connected to the wire 106 passed to the motor 9.
2. Further, a high voltage power source 108 is supported on the slider 98, and terminals 108a and 108b are formed toward the slider 102.

As shown in FIG. 1, the slider 102 of the contact screen cartridge 20 has a pair of rollers 11.
0 and 112 are attached at a predetermined angular relationship.

That is, one roller 112 is connected to the contact screen 40.
The other roller 110 is located above the roller 112 on the side remote from the contact screen 40 .

The contact screen 40 has a pair of rollers 110,1
12 in an S-shape, and its lower end is connected to one roller 1.
12 and is fixed to the lower end of the contact screen cartridge 20 by a pin 114 after passing over the other roller 110 and its upper end is secured to the lower end of the contact screen cartridge 20 by a spring 116 after passing over the other roller 110.
It is fixed to the upper end of the contact screen cartridge 20 via the contact screen cartridge 20 (FIG. 12). Spring 116 provides constant tension to contact screen 40. Terminal 108a of the high voltage power supply 108.

108b is brought into contact with these rollers 110, 112.

Therefore, when the shading holder 88 assumes the operating position directly facing the vacuum box 32b as shown in FIG. It comes into close contact with the front surface of the vacuum box 32b. Conversely, the roller 11 along with the slider 102
0, 112 is lowered, the contact screen 40
is released from the pressure of the roller 110 and continuously peels off from the front surface of the vacuum box 32b. With this configuration, the photoconductor charged by the charging devices 52 and 54 is transferred to the contact screen 4 on the vacuum box 32b.
Even if it was brought into close contact with zero, no discharge damage occurred.

13 and 14 are detailed views of the second exposure means 56. FIG. The photoreceptor is supported between a pair of pinch rollers 50 and is driven and supplied. Inside the case 120, a reflecting plate 122 is provided on the rear side of the second exposure light source 56a, and a light guide opening 126 is provided on the front side through an infrared absorption filter 124.
A liquid crystal shutter 128 having approximately the same length as the width of the photoreceptor is arranged outside the photoreceptor 26. The liquid crystal shutter 128 is the fourteenth
As shown in the figure, a large number of rectangular liquid crystal portions 128a are provided, and each liquid crystal portion 128a is energized and controlled by a driving portion 128b.

Further, a SELFOC lens 130 is disposed between the photoconductor and the liquid crystal shutter 128, and the light passing through each liquid crystal section 128a forms an image on the photoconductor, thereby exposing the charged portion on the photoconductor. can be controlled. Each liquid crystal section 12
The energization control of 8a is performed according to the contents stored in the IC card 16, for example, the mark 86a.

The areas inside 86b and 86c are exposed. Conversely, it is also possible to expose the areas outside the marks 86a, 86b, and 86c.

FIG. 15 is a diagram showing the configuration of the control device 140 of the color separation electrophotographic plate making machine. The control device 140 is configured as a microcomputer, and includes a central processing unit (CPU) 142 that has calculation and control functions, a read-only memory (ROM) 144 that stores programs, and a random access memory that stores data, etc. (RAM) 146
and a presettable counter (CO04B), which are interconnected by a bus 150, and
Receives inputs from the key matrix 12, each sensor such as a path sensor, and the IC card 16 via an input/output (Ilo) interface 152, and outputs various outputs 1 from each motor, light source, etc.
56 and display 14.

Next, the operation of the color separation electrophotographic plate-making machine having the above configuration will be explained with reference to the flowcharts from FIG. 16 onwards.

FIG. 16 schematically shows the operation of the plate-making machine, and step 160
Initialize is performed in step 161, the position of the keys on the operation panel 120 is read, the IC card 16 is read in step 162, the output of various sensors is read in step 163, and each part is read from the key position and sensor output in step 164. determines the operation of the motor, light source, etc.

FIG. 17 shows the operations of the main parts roughly classified. For example, a paper feeding operation 170 in which the photoreceptor is advanced along a supply path or an ejection path, a charging operation in a charging device 52 and 54,
A trimming operation 172 for exposing a partial area of the photoreceptor with the second exposure means 56, a halftone operation 173 for operating the halftone contact screen 40, a color separation operation 174 for operating the color separation filter 38, and a first Exposure means 30
Exposure operation 175 to operate, development operation 176 after exposure
, a fixing operation 177, a brieching operation 178, etc. are performed. Hereinafter, only important operations in the present invention will be explained in detail with reference to FIGS. 18 to 21.

FIG. 18 is a flowchart showing the trimming operation. This operates depending on whether or not the trimming key shown in FIG. 3 is selected, for example.

First, in step 180, it is determined whether or not the photoreceptor serving as the master paper has come to a paper feed sensor (not shown) provided in front of the pinch roller 46, for example. Proceed to. In step 181, it is determined whether the trimming function is selected. If the trimming key in FIG. (not shown) is rotated at high speed, and the photoreceptor is rapidly transported to the vacuum box 32. In this case, the second exposure means 56 is not operated, and the photoreceptor is then exposed to the first exposure means 3.
The entire surface is exposed by 0.

If the trimming key in FIG. 3 is pressed, the determination in step 181 is YES, and in this case, the process advances to step 183, where the LCS motor that drives the pinch roller 50 is rotated at a low speed to slowly feed the photoreceptor. Meanwhile, in step 184, an LCS sensor (not shown) determines whether the photoreceptor has reached a predetermined exposure position. Step 184
If the determination is YES, the process proceeds to step 185 and starts a timer for generating image data output timing.
Further, the process proceeds to step 186 and the second exposure light source (LSC lamp) 56a is turned on. Next, in step 187, it is determined whether the timer started in step 185 has counted up, and if the answer is YES, the process proceeds to step 188 and output of image data is started.

In step 188, image data corresponding to I life is extracted from the memory contents of the IC card 16. Then, in step 189, the 1947 worth of image data is written into the second exposure means 56. This is the liquid crystal shutter 128 of the second exposure means 56.
By energizing each liquid crystal section 128a (Fig. 14), which forms dots, the light of the second exposure light [56a] is passed through in dots according to the stored contents, and an image is formed on the photoreceptor (K in Fig. 13). That's true. While advancing the photoreceptor, writing of image data for 1947 minutes is continued, and in step 190 it is determined whether writing of all data has been completed.

If the judgment in step 190 is yes, step 19
1, the second exposure light source (LSC lamp) 56a is turned off. In step 192, it is determined whether the claw stop sensor is turned on, that is, whether the gripper claw 32f of the photoreceptor support means has gripped the photoreceptor, and when the answer is YES, the LCS motor is stopped. This completes the trimming operation.

In this trimming operation, for example, mark 8 in FIG.
6a, the irradiation area of the second exposure means 56 can be selected to be either the area inside the mark 86a or the area outside the mark 86a. Therefore, first, the photoreceptor is cut into a predetermined length from the photoreceptor roll 42 by the cutter device 42a, and the charging device 52 charges the photoreceptor, and the second exposure means 56 irradiates the area inside the mark 86a, and supports the photoreceptor. It can be exposed by the first exposure means 30. In this case, mark 86
Since the area inside the mark 86a is discharged by the exposure of the second exposure means 56, no image of the document is formed in this area even if it is exposed by the first exposure means 30, and an image of the original is not formed in the area outside the mark 86a. Only images are formed. The thus completed photoreceptor is developed and fixed on the way, and then discharged to the second discharge port. This photoreceptor on which an image has already been formed is inserted through the cut photoreceptor supply port 26 and charged by the charging device 54 . Since fixing was performed during the previous ejection, the previously formed image is not affected at all, and the entire surface of the photoreceptor is charged. Therefore, the mark 86a is now exposed by the second exposure means 56.
It is possible to irradiate the outer area of the photoreceptor and send it to the photoreceptor support means to be exposed again by the first exposure means 30. This time, since the region outside the mark 86a is discharged by the exposure of the second exposure means 56, an image is formed by the first exposure means 30 only in the region inside the mark 86a. In this way, first a color photo insurance is obtained inside the mark 86a on the photoconductor, and then a mark 86a on the same photoconductor is obtained.
It is also possible to obtain a monochrome image of line drawings, letters, etc. on the outside of the image.

FIG. 19 is a flowchart showing the color separation operation of the color separation filter 38 of FIG. In step 200, it is determined (by a sensor not shown) whether the photoreceptor has stopped at a predetermined position of the vacuum box 32b of the photoreceptor support means, and if the answer is YES, the process advances to step 201 and the color separation filter key is pressed. determine whether there is.

If no, the process ends. In addition, color separation filter 3
8 is a blue-violet (B) filter 38e1 green (G) filter 38
f, a red (R) filter 38g, and a window 38h for when color separation is not performed, and the window 38h is normally placed in a fixed position aligned with the lens 36. Therefore, if the answer in step 201 is NO, it is possible to perform a back-and-back shadow without color separation. Further, the filter mounting plate 38a of the color separation filter 38 is rotated by a pulse motor 38i, and a desired filter can be selected by selecting the number of pulses.

If step 201 is yes, then step 2
Step 02 determines whether the blue-violet (B) filter 38e is selected. If yes, step 204 sets the number of pulses necessary to select the blue-violet (B) filter 38e in a predetermined counter. - Throat. If the answer in step 202 is NO, step 203G proceeds to determine whether green (G) filter 38f is selected. If yes, proceed to Step 206 and display the green (
C) Set the number of pulses necessary to select the filter 38f, and if NO, proceed to step 205 and set the number of pulses necessary to select the red (R) filter 38g in the counter. Next, in step 207, an interrupt is enabled when the filter moving pulse motor 38i is stopped, and in step 208, the filter moving pulse motor 38i is rotated, and when the selected number of pulses is reached, a counter interrupt signal is input. Pulse motor 3 for moving the filter
Stop 8i. Then, when the process proceeds to step 209 and it is determined that the exposure by the first exposure means has been completed,
In steps 210, 211, and 212, the filling movement pulse motor 38i is returned to its home position.

FIG. 20 is a flowchart showing the halftone operation of the halftone contact screen 40. As described above, the contact screen 40 is housed in the contact screen cartridge 20 and can take an inoperative position at an angle with the vacuum box 32b and an active position directly facing the vacuum box 32b, and is continuously vacuumed by the rollers 110 and 112. The box 32b was adhered to and peeled off before. Further, the rollers 110 and 112 can be applied with a high voltage neutralizing voltage from the high voltage power supply 10B via the terminals 108a and 108b.

Steps 220 through 226 illustrate nine preliminary static neutralization operations of the contact screen 40 performed in the inactive position where the ζ contact screen 40 forms an angle with the vacuum box 32b. In step 220, the high voltage power supply 108
& related gear is turned on, and in step 221, the roller moving motor 92 for moving the rollers IJ0, 112 (slider) is rotated in the forward direction, and the rollers 110, 11 are rotated in the normal direction.
2 from the lower end position to the upper end position. Step 22
2, a roller stop sensor (not shown) detects the roller 110,
When detecting that 112 has reached the upper end position, step 2
23, the roller moving motor 92 is reversed, and the roller 110
, 112 from the upper end position to the lower end position. In step 224, when the roller origin sensor (not shown) detects that the rollers 110 and 112 have reached the lower end position,
In step 225, the roller moving motor 92 is stopped.

Therefore, the rollers 110 and 112 reciprocate once from the lower end to the upper end of the contact screen 40 while being applied with high pressure, thereby eliminating static electricity and the like adhering to the contact screen 40. Then, in step 226, the high voltage power supply 108 and the relay are turned off.

Next, in step 227, the photoconductor is
2b, and if the answer is YES, the process proceeds to step 228, where the cassette/seat moving motor (not shown) is rotated in the forward direction to rotate the contact screen 40 to the operating position directly facing the vacuum box 32b. Then, in step 229, a sensor (not shown) is used to determine whether the contact screen 40 has come to the operating position.

If the answer is YES, the cassette moving motor is stopped in step 230, and the roller moving motor 92 is rotated normally again in step 231 to move the rollers 110 and 112 from the lower end position to the upper end position. At this time, the contact screen 40 is continuously brought into close contact with the front surface of the vacuum box 32b. At the same time, in step 232, the high voltage power supply 10
8 and turn on the relay.

In step 233, the roller stop sensor detects that the roller 110°1
When it is detected that 12 has reached the upper end position, step 23
4, the roller moving motor 92 is stopped. Then, in step 235, the high voltage power supply 108 and the relay are turned off. In this state, take a photo.

When it is determined in step 236 that the exposure has been completed, the roller moving motor 92 is reversed in step 237, and the roller 1
10 and 112 from the upper end position to the lower end position, and at the same time, the high voltage electric current tA 108 and the relay are turned on using the step 238. When the roller origin sensor detects that the rollers 110 and 112 have reached the lower end position in step 239, the roller moving motor 92 is stopped in step 240, and the high voltage power supply 108 and relay are turned off in step 241. Then, in step 242, the cassette movement motor is reversed to rotate the contact screen 40 to an angular inoperative position with respect to the vacuum box 32b, and in step 243, the cassette adhesion sensor detects whether the contact screen 40 has come to the inoperative position. to judge.

Once the inactive position is reached, the cassette movement motor is stopped in step 244.

FIG. 21 is a flowchart showing the exposure operation of the first exposure means 30.

At step 250, a wait process is performed until the start of exposure.

Steps 251 to 259 are main exposure time calculations, and steps 260 to 269 are flash exposure time calculations.

The main exposure time is determined by multiplying the main exposure index by a coefficient depending on the presence or absence of various operations, the type of photoreceptor, etc. First, in step 251, it is determined whether the photoreceptor (mask) is A. If YES, the exposure index is multiplied by the coefficient of master A in step 252, and if NO, the coefficient of master B is multiplied in step 253. Next, in step 254, it is determined whether to shade or not, and if yes, step 25
5 multiplies the exposure index by the shading coefficient. Next step 2
In step 56, it is determined whether or not to perform color separation, and if yes, in step 257, the exposure index is multiplied by the coefficient of each filter. In step 258, a predetermined correction value is applied to the exposure index. Then, in step 259, the calculated value is set in a counter as the exposure time.

In step 260, it is determined whether or not to perform flash exposure. If yes, the process proceeds to step 261; if no, the process jumps to step 270.

If flash exposure is used, calculate the flash exposure index. Steps 261 to 26 in this case
Since the processing up to Step 9 is the same as the processing from Steps 251 to 259 for calculating the main exposure index, detailed explanation will be omitted.

Next, in step 270, it is determined whether to perform flash exposure again, and if yes, the process proceeds to step 275.
If no, the process advances to step 271.

In step 271, only the main exposure lamp 30a is turned on, in step 272 the main exposure time is counted down, and in step 273 it is determined whether the main exposure time has counted up. If the answer is YES, the process proceeds to step 274, where the main exposure lamp 30a is turned off and the process ends.

If the answer in step 270 is NO, then in step 275 both the main exposure lamp 30a and the flash exposure lamp 31 are turned on. Then steps 276, 277,
At 278, the main exposure time is counted down, it is determined whether the count has increased, and if the count is YES, the main exposure lamp 30a is turned off.

Furthermore, in steps 279, 280, and 281, the flash exposure time is counted down, and it is determined whether the count has increased. If the count is YES, the flash exposure lamp 31 is turned off. Finally, in step 282, it is determined whether the main exposure lamp 30a and flash exposure lamp 31 are both turned off, and if no, the process returns to step 276. If the answer is yes, the process ends.

〔Effect of the invention〕

As explained above, according to the present invention, color photography can be performed by the first exposure means, the first exposure means, the color separation filter, the contact screen, and the photoreceptor support means for image formation, and A second exposure means disposed between the charging means and the photoreceptor supporting means for image formation exposes a small area of the photoreceptor to light, thereby reducing the influence of halftone dots caused by a contact screen during color photography. In addition, the contact screen is continuously attached to or peeled off from the photoreceptor by a movable roller, which prevents electrical discharge damage to the charged photoreceptor and improves electrophotography. This makes it possible to use a contact screen in a plate-making machine. Therefore, according to the present invention, it is possible to obtain a color-separating electrophotographic plate-making machine that can be easily operated and can produce a desired color printing plate.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of a color separation electrophotographic plate making machine according to the present invention, Fig. 2 is a perspective view showing the external appearance of the color separation electrophotographic plate making machine shown in Fig. 1, and Fig. 3 is an operation of the color separation electrophotographic plate making machine shown in Fig. 2. A detailed view of the panel, Figure 4 is a perspective view of the trimming area input device that is an accessory, and Figure 5 is a detailed view of the panel.
The figure shows the numeric keypad in Figure 4, Figure 6 is a perspective view of the image scanner used in the human-powered device in Figure 4, and Figure 7 shows the transparent plate on the document base to be applied to the image scanner in Figure 6. 8 is a diagram showing the configuration of the document mount shown in FIG. 7, FIG. 9 is a perspective view showing the document mount shown in FIG. 1, and FIG. A perspective view showing a color separation filter, FIG. 11 is an enlarged view of the photoreceptor support means and the shading contact screen shown in FIG. 1, and FIG. 12 shows the contact screen cartridge and cartridge holder shown in FIGS. 1 and 11. Figure 13 in the removed state
The figure is a detailed view of the second exposure light source in Figure 1, and Figure 14 is a detailed view of the second exposure light source in Figure 1.
15 is a configuration diagram of the control device, FIG. 16 is a flowchart showing the outline of the control of the color separation electrophotographic engraving machine shown in FIG. 1, and FIG. 18 is a flowchart showing the trimming operation, FIG. 19 is a flowchart showing the color separation operation, FIG. 20 is a flowchart showing the shading operation, and FIG. 21 is a flowchart showing the exposure operation. . DESCRIPTION OF SYMBOLS 10-outer case, 22, 24--discharge port, 26--slit photoreceptor insertion port, 2B--document placement table, 30--first exposure means, 30a--first exposure lamp, 32--. Photoreceptor support means, 38--color separation filter, 40-contact screen, 42, 44-photoreceptor roll, 46, 4B, 50, 58--pinch roller,
56.-Second exposure means, 56a-.-Second exposure lamp, 110, 112-Roller. Figure collection Figure 10, 140 Figure 20 (Part 2)

Claims (1)

[Claims] A document placement table and a first document placement table provided in relation to the document placement table.
an exposure means, a photoreceptor support means formed at a predetermined position to receive light from the first exposure means and form an image, and a photoreceptor supported along a predetermined supply path to the photoreceptor support means. A photoreceptor supplying means, a color separation filter provided between the document placing table and the photoreceptor supporting means, and a movable roller continuously contacting or contacting the photoreceptor on the photoreceptor supporting means. A meshing contact screen to be peeled off, a charging means that is located in the middle of the predetermined supply route and charges the photoreceptor, and a contact screen that is located between the charging means and the photoreceptor supporting means in the middle of the predetermined supply route. and exposing at least a partial area of the photoreceptor charged by the charging means to light.
A color separation electrophotographic engraving machine comprising an exposure means and a discharge means for discharging the photoconductor exposed by the first exposure means from the photoconductor support means to an discharge port.