JP2983661B2 - Multicolor printing press - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-color printing machine for printing using a plurality of colors of ink.

[0002]

2. Description of the Related Art Conventionally, various types of multicolor printing presses capable of performing printing with a plurality of colors by one unit have been provided. For example, in a rotary press, a pair of printing drums and press rollers that rotate while being in contact with each other are arranged as a unit in a number corresponding to the number of colors, and printing paper is sequentially placed between the printing drum and the press rollers of each unit. There is known an apparatus in which printing is performed in a plurality of colors by passing the print.

[0003]

As a multi-color printing press of this type, in an offset printing press, the ink transferred from the printing drum to the paper is prevented from being transferred to the printing drum of the next unit. Is provided with a dryer. However, such a configuration of the printing machine requires a large number of dryers, resulting in a problem that the cost of the apparatus increases.

As a method for drying the ink, in addition to providing a dryer, for example, it is conceivable to lengthen the span between the units. However, this method has a problem in that the size of the printing press becomes large. Particularly, in a printing press such as a stencil printing press which uses a relatively large amount of ink, it is necessary to separate the units considerably, so that an apparatus is required. It is too large and difficult to achieve.

Accordingly, a technical problem to be solved by the present invention is that a multi-color printing press of a type which can suppress an increase in cost and size of a printing press using only one ink and which is particularly suitable for a stencil printing press. Is to provide.

[0006]

In order to solve the above-mentioned technical problems, a multicolor printing machine according to the present invention is configured as follows. That is, the printing apparatus includes a plurality of printing drums and a sheet conveying unit having a sheet holding unit that circulates on a predetermined track surface, and each printing drum and the track surface are disposed so as to be relatively close to and separated from each other. And a paper supply unit for supplying paper to the paper holding unit of the transport unit;
Paper discharge means for taking out the paper from the paper holding means of the transport means, and control means for pressing a different printing drum and a track surface relative to each other with each time one sheet of printing paper circulates on the track surface And

In the above arrangement, the printing paper is supplied from the paper feeding means to the holding means and circulates on the track surface of the conveying means. At this time, each time the printing paper circulates on the raceway surface, a different printing drum and the raceway surface are relatively pressed with the paper therebetween. Therefore, if the color of the ink printed on each printing drum is changed, printing can be performed in a different color each time the paper circulates. In this configuration, although it depends on the length of the track, in order to completely dry the printed ink, every time the paper is circulated twice or three times, one time is required.
It is preferable to print each color.

[0008] In the printing press having the above-mentioned configuration, a plurality of drums do not operate at least while the paper circulates once.
Therefore, since the ink transferred to the paper can be sufficiently dried during the circulation, it is possible to prevent an increase in the size of the printing press due to an increase in the span between the printing drums. It becomes possible. Further, since the ink is sufficiently dried by circulating the paper several times without providing a drying unit, it is possible to prevent an increase in the cost of the printing press.

In the above-mentioned construction, the paper transport means may include the same number of press rollers as the print drums and the belt means which is wound around the press rollers and passes between the print drums and has the paper holding means. And drive means for circulating the belt means, each press roller can be individually configured to be able to contact and separate from the corresponding print drum, and further, drying means can be provided around the belt means. .

With this configuration, the belt means is circulated while the printing paper is held by the holding means, and the press roller is pressed against the printing drum every time the printing paper circulates on the track surface. Printing can be performed sequentially for each color. In this configuration, since the drying unit is provided around the belt, the ink can be completely dried each time the paper circulates once. Moreover, since the drying means only needs to be provided at one place, it is possible to prevent an increase in the size and cost of the apparatus.

In the above construction, the paper transport means comprises a single paper transport roller having a diameter larger than that of the printing drum and having a paper holding means on its surface, and a driving means for driving the roller to rotate. The printing drum can be configured to be able to contact and separate from the surface of the transport roller, and a drying unit can be provided around the transport roller.

[0012] Even with this configuration, it is possible to print one color each time the paper is circulated once around the conveying roller, and to provide a drying unit at one location, thereby increasing the size and cost of the apparatus. Can be prevented.

Further, in each of the above-described configurations, it is preferable that at least the same number of paper holding units as the number of printing drums are provided on the track surface of the conveying unit.

With this configuration, at least the same number of sheets as the number of printing drums circulate on the track surface at the same time. Therefore, by pressing different printing drums for each sheet, printing can be performed using different inks in order for different sheets, so that multicolor printing can be performed extremely efficiently.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a multicolor printing machine according to a first embodiment of the present invention shown in FIGS. 1 to 14 will be described in detail. FIG. 1 is a schematic internal configuration diagram of the printing press. In FIG. 1, reference numeral 1 denotes a document reading unit for reading a document in order to make a plate, reference numeral 2 denotes a document table on which a cover 2a can be opened and closed, and reference numeral 3 denotes a document table for irradiating light on the document placed on the table 2. A fluorescent lamp 4 is a color CCD (charge-coupled device) that outputs an electric signal corresponding to the color of the original when the reflected light on the original surface is guided by several mirrors as indicated by a one-dot chain line and enters. is there. The light source and the mirror can be moved to the left from the illustrated position to scan the document surface.

Reference numeral 5 denotes a plate-making printing section comprising a plate-making section 5a for making a plate based on an output signal from the color CCD 4 and a printing section 5b for printing using the plate. The plate making section 5a includes a base paper roll 6 on which a long base paper is wound, a thermal head 7a, a platen roller 7b for pressing the base paper against the thermal head 7a, and several feed rollers 8
Here, the four base papers are subjected to plate making in correspondence with the colors of the originals (black, blue, red, and yellow in this embodiment). On the other hand, the printing unit 5b is configured such that the printing drums 9a to 9d and the press rollers 12a to 12d configured to be able to take the positions in contact with and away from the printing drums 9a to 9d by being driven by an air cylinder or the like. 12d. Each of the printing drums 9a to 9d is hollow and has two rollers 22a and 22b inside, and the rotation of these rollers causes the screen 23 to be uniformly kneaded between the rollers.
(FIG. 2) is applied from the back side. Black, blue, red, and yellow inks are applied to the printing drums 9a to 9d in order from the upper side. Further, as shown in FIG. 2, each of the printing drums 9a to 9d has clamps 10A to 10D for holding the base paper wound on its surface. The clamps 10A to 10D include a pair of claws 10a and 10b which can be opened and closed around the shaft 10c and are provided in the longitudinal direction of the shaft 10c, respectively, and a cam follower 10d fixed to an end of the shaft 10c. I have. The cam follower 10d is swung by driving a cam (not shown) provided on the main body of the printing machine as needed, and the pawls 10a and 10b are opened and closed.

As shown in FIG. 1, press rollers 12a to 12a
A belt 14 is stretched between 12d and a driving roller 13a and a tension roller 13b disposed on the right side of the belt 12d, and these constitute a printing paper conveying means 11. The belt 1 has a clamp 1 as a sheet holding means for holding four printing sheets at different positions.
5 are provided at four places. In addition, each printing drum 9a
In the position on the front side of the paper traveling direction (indicated by the arrow in the figure) with respect to the paper drums 9a to 9d, the paper is sprayed on the belt 14 side to cause the paper A fan 16 for stabilizing the entry of the vehicle is arranged. Further, two infrared lamps 17 as ink drying means are provided in a vacant portion (lower right portion of the driving roller 13a in this embodiment) behind the printing drum 9a around the belt 14 in the traveling direction of the paper. One UV lamp 18
Is provided. The printing drums 9a to 9d are also provided at positions rearward of the lamps 17 and 18 in the paper traveling direction.
Three fans 19 are arranged to urge the sheet toward the belt 14 as in the case of the section.

Here, paper feeding means 20 for supplying paper to the clamp 15 and the paper 1 on which printing has been completed
Next, a description will be given of the sheet discharging means 21 for taking out the sheet 5.
The paper feeding means 20 is composed of a combination of large and small rollers, and feeds the paper one by one from the stocked portion to the clamp 15 by the rotation of a large-diameter roller 20a that presses the upper surface of the stocked printing paper. Also, the belt 14
Shows two toothed belts 14a as shown in detail in FIG.
And a screen 14b located therebetween. The clamp 15 is provided with two toothed belts 14.
a plurality of claws 15a formed on a shaft 15c fixed in a direction orthogonal to a, and a rotating shaft 15d extending in the same direction as the shaft 15c.
And a cam follower 15e fixed to the end of the shaft 15d to rotate the shaft 15d, and the paper can be held between the claws 15a and 15b. it can. Further, a cam (not shown) of the printing press main body can be driven to release the paper as needed.

On the other hand, a guide plate 21 shown in FIG. 4, which is a perspective view seen from below, is provided as a sheet discharging means. The guide plate 21 has a shape in which the end on the side of the belt 14 is curved upward, and a notch 21
a are formed at regular intervals. The pawls 15a and 15b of the clamp 15 provided on the belt 14 can pass through the notches 21a. At this time, the pawls 15a and 15b can be opened to receive the paper from the belt 14. ing.

Next, the control relationship of the printing press will be described with reference to the block diagram shown in FIG. In the figure, reference numeral 100 denotes a plate making control CPU for controlling the operation of each part during plate making.
(Central processing unit), 101 is a plate making control circuit, 10
Reference numeral 2 denotes a print control CP connected so as to be able to exchange signals with the plate making control CPU 100.
U. When the operation panel 103 provided on the outer surface of the printing press is operated, the plate making control CPU 100 drives the scanner motor 104 for moving the light source 3 and the like for scanning the document surface, and the platen roller 7b. The motor is connected to these motors 104 and 105 for starting the platen motor 105.
The plate making control circuit 101 includes a color CCD sensor 4, an external interface 106 (for connecting a word processor to perform printing based on an electric signal without printing a document), and a thermal head 7a. Connected, CCD
The thermal head 108 is started according to signals from the sensor 4, the external interface 106, and the plate making control CPU 100.

On the other hand, the print control CPU 102
The operation panel 103 is connected to a drum encoder 107 for detecting the state of the printing drums 9a to 9d and a belt encoder 108 for detecting the state of the belt 14. Signals from these are input and the printing drums 9a to 9d are connected.
9d, press rollers 12a to 12d, and drive roller 13a
Are connected to a main motor 109 for driving the motor. The print control CPU 102 also includes solenoid valves 110a to 110d for switching actuators such as air cylinders for separately pressing the press rollers 12a to 12d against the print drums 9a to 9d during printing, and opening and closing clamps 10A for the print drums 9a to 9d. And motors 112a to 112d provided to finely move the printing drums 9a to 9d in order to adjust a color shift that may occur when printing each color with another roller. It is connected to the.

In this printing machine, when a document is read, four plates corresponding to each color of the document surface are produced.
Then, each plate is fed from the feed roller 8 to the clamp 1 of the belt 14.
5 is transferred one by one, and further sent to a printing drum corresponding to each color. FIG. 6 shows a state where the plate is transferred from the belt 14 to each of the drums 9a to 9d (however, the plate is omitted). Claws 15a, 15b of the clamp 15 of the belt 14
Are clamps 10 of the printing drums 9a to 9d as shown in FIG.
It is formed so as to be located between the claws 10a and 10b of A to 10D. Therefore, if the claws 10a and 10b of the clamp 10 are opened when the clamp 15 holding the plate-making base paper passes through the portion of the clamp 10 on the printing drum side, the gap between the claws of the belt-side clamp 15 A portion of the base paper that is not held is held by the print drum side clamp 1.
It enters between the claws 10a and 10b of 0A to 10D. At this time, the printing drums 9a to 9d are moved downward by the fine movement motors 112a to 112d almost simultaneously with closing the claws 10a and 10b of the drum side clamp 10 (the claws 15b of the belt side clamp 15 are closed). (To avoid being attracted to the surfaces of the drums 9a to 9d) and the belt side clamp 1
By opening the claws 15a and 15b, the base paper is
4 to the print drum. Thereafter, ink is supplied to the plate by the above-described method, and the printing paper is supplied to each drum 9a.
Printing can be performed by pressing the printheads on to 9d.

Next, the movement of the paper and the press roller during printing will be described with reference to FIGS. FIG. 7 illustrates a state in which the first sheet is supplied to the clamp 15 </ b> A provided on the belt 14 by the paper supply unit 20. At this time, the press rollers 12a to 12d are all set at positions away from the printing drums 9a to 9d. On the other hand, as shown in FIG.
And passes between the lowermost drum 9d and the press roller 12d when the solenoid 110d described with reference to FIG.
Is switched, the press roller 12d is pressed toward the print drum 9d, and printing of the first color (yellow) is performed. This sheet is printed by the printing drums 9b to 9d and the press roller 1
When passing between 2b and 12d, each press roller 12b
-12d maintain positions away from the printing drums 9b-9d. Therefore, at this stage, the paper is not printed in the second and subsequent colors at this stage, as shown in FIG.
8 through which the yellow ink is dried.

The printing paper is further advanced and the paper feeding means 20
, The second sheet is supplied to the next clamp 15B as shown in FIG. At this time, the press rollers 12a to 12d are connected to the print drums 9a to 9d.
Is set at a position distant from
The first sheet simply passes between the yellow ink drum 9d and the press roller 12d which are separated from each other. When the paper passes between the red ink drum 9c and the press roller 12c as shown in FIG. 11, the press roller 12c is pressed against the print drum 9c and printing with the red ink is performed. Press roller 12
d is pressed against the printing drum 9d side, and printing with yellow ink is performed on the second sheet. As these papers move up from there, each drum 9a, 9b, 9c
The press rollers 12a, 12b, and 12c are separated from each other, so that printing with blue and black ink is not performed on the first sheet, and printing with red, blue, and black ink is performed on the second sheet. No printing is performed. And each paper is
As shown in (2), the process proceeds to ramps 17 and 18, where the red ink is dried on the first sheet and the yellow ink is dried on the second sheet.

When the belt 14 continues to rotate and the second sheet passes through the paper feeding means 20, the third sheet is supplied to the belt 14, though not shown. By the same movement as described above, printing with the blue ink on the first sheet, printing with the red ink on the second sheet, and printing with the yellow ink on the third sheet were performed. Thereafter, drying of each ink by the lamps 17 and 18 is performed.

When the third sheet passes through the paper feeding means 20, the fourth sheet is moved to the belt 14 as shown in FIG.
Is supplied to the clamp 15D. By pressing the press roller corresponding to each sheet toward the printing drum, printing is performed with black ink on the first sheet, blue ink on the second sheet, red ink on the third sheet, and yellow ink on the fourth sheet. It is. Then, in order to more reliably dry the ink on the first sheet, the first sheet is discharged from the guide plate 21 as shown in FIG. Another sheet is supplied to the clamp 15A holding the sheet. When the printing is completed in this manner, the base paper wound around the print drums 9a to 9d is taken up by a base paper take-up roller 24 (FIG. 1) provided on the left side thereof.

As described above, in the printing press described above, 1
Paper feed, yellow printing, drying, red printing, drying, blue printing, drying, black printing, drying, drying for each sheet of paper (the last drying step is also drying, which can be omitted to shorten printing time) Since the ink is dried while the printing paper is circulated during the paper discharging process, the problem of increasing the size of the apparatus by increasing the span between the printing drums does not occur. Even if the lamps 17 and 18 are not necessarily provided, it is possible to sufficiently dry the ink by printing one color each time the paper is circulated several times, thereby further increasing the cost of the printing press. In this embodiment, the lamps 17 and 18 are provided as drying means in order to reduce the time required for printing.

Next, a second embodiment of the present invention shown in FIG. 15 will be described. The document reading unit provided at the upper part of the printing press has the same configuration as that of the first embodiment, and a description thereof will be omitted. In this printing machine, the paper conveying means 50 is not constituted by a plurality of press rollers and belts, but is constituted by a single large roller 57. And, from the left,
Four printing drums 5 for printing with red, blue and black inks
1, 51b, 51c, 51d are provided so as to be able to take a position in contact with the surface 50a of the roller 57 and a position apart therefrom. 52 is a base paper roll, 53
Is an openable / closable clamp 5 provided on the surface of the roller 57.
A paper feeding unit 54 for supplying printing paper to the printer 5 and a paper discharging unit 54 for taking out the printed paper from the clamp 55. In the vacant portion below the roller 57, several lamps 56 are arranged as a drying means as in the first embodiment.

In the printing machine of this configuration, when the first sheet is supplied, only the yellow ink printing drum 51a is controlled to be pressed against the roller 57 to perform printing only with yellow ink. When the first sheet is supplied, the red ink drum 51b is pressed against the roller 57 when the first sheet passes, and the yellow ink drum 51a is pressed against the roller 57 when the second sheet passes. By pressing the second sheet, the first sheet is printed with red ink and the second sheet is printed with yellow ink. In this manner, by printing one color at a time for each rotation of the roller 57, printing in yellow, red, blue, and black can be performed on one sheet, similarly to the first embodiment. The paper on which printing has been completed is discharged from the paper discharging means 54, new paper is supplied to the empty clamp, and printing in each color is performed in the same manner. Also in this configuration, since the configuration is such that the printing paper is circulated, it is possible to prevent the cost and size of the printing press from increasing.

[Brief description of the drawings]

FIG. 1 is a schematic internal configuration diagram of a multicolor printing press according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a printing drum.

FIG. 3 is a perspective view of a belt-side clamp unit for printing paper.

FIG. 4 is a perspective view of a sheet discharging means.

FIG. 5 is a block diagram showing a control relationship of the printing press.

FIG. 6 is a perspective view illustrating a relationship between a belt and a printing drum.

FIG. 7 is a diagram illustrating a state of paper feeding to a belt.

FIG. 8 is a diagram illustrating a printing state of a sheet.

FIG. 9 is a diagram illustrating a dry state of a sheet.

FIG. 10 is a diagram illustrating a paper feeding state of a second sheet.

FIG. 11 is a diagram illustrating a printing state of different colors on each sheet.

FIG. 12 is a diagram illustrating a dry state of a sheet.

FIG. 13 is a diagram illustrating a sheet feeding state of a fourth sheet.

FIG. 14 is a diagram illustrating a state in which a sheet is discharged.

FIG. 15 is a schematic internal configuration diagram of a multicolor printing machine according to a second embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 document reading section 2 document table 2 a cover 3 light source 4 color CCD 5 plate making printing section 5 a plate making section 5 b printing section 6 base paper roll 7 a thermal head 7 b platen roller 8 feed roller 9 a to 9 d printing drum 10 clamp 10 a, 10 b nail 10 c shaft Reference Signs List 10d cam follower 11 paper conveying means 12a-12d press roller 13a drive roller 13b tension roller 14 belt 14a toothed belt 14b screen 15 clamp 15a, 15b claw 15c, 15d shaft 15e cam follower 16 fan 17 infrared lamp 18 ultraviolet lamp 19 fan 20 Means 20a Roller 21 Discharge means (guide plate) 22a, 22b Roller 23 Screen 24 Raw paper take-up roller 50 Paper transport means 51a to 51d Printing drum 52 Raw paper roll 53 Paper feed means 54 Paper discharge means 55 Lamp 56 Lamp 57 Conveyor roller 100 Plate making control CPU 101 Plate making control circuit 102 Print control CPU 103 Operation panel 104 Scanner motor 105 Platen motor 106 External interface 107 Drum encoder 108 Belt encoder 109 Main motor 110a to 110d Solenoid valve 111a to 111d Clamp motor 112a-112d Drum motor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41L 13/04 B41L 13/16 B41F 7/02 B41F 9/00-9/02 B41F 5/02 B41F 15 / 08

Claims (4)

(57) [Claims] A plurality of printing drums (9, 51) and a sheet conveying means (11, 50) having a sheet holding means (15, 55) circulating on a predetermined track surface (14, 50a). Equipped with each of the above printing drums (9,
Paper feed means for supplying paper to the paper holding means (15, 55) of the transport means (11, 50), wherein the track surface (14, 50a) and the track surface (14, 50a) are relatively detachably disposed; (20,53) and the transport means
A sheet discharging means (21, 54) for taking out a sheet from the sheet holding means (15, 55) of (11, 50);
Each time it circulates above, a different printing drum (9,51) and its track surface
(14, 50a), and control means (102) for relatively pressing the sheet with the sheet interposed therebetween. 2. The printing apparatus according to claim 1, wherein the paper transport means includes a plurality of press rollers, the same number as that of the printing drum.
Belt means (14) which is wound around 2), passes between the printing drum (9) and has the paper holding means (15),
A driving means (109) for circulating the belt means (14), wherein each of the press rollers (12) is configured to be able to be individually brought into contact with and separated from a corresponding printing drum, and the belt means (14)
2. The multi-color printing press according to claim 1, wherein drying means (17, 18) are provided around the printing apparatus. The paper transport means (50) has a single paper transport roller (57) having a diameter larger than that of the printing drum (51) and having the paper holding means (55) on the surface thereof; 57) and a driving means (109) for driving the rotation of the printing drum (5).
1) is configured to be able to contact and separate from the surface of the transport roller (57), and drying means (56) around the paper transport roller (57).
The multi-color printing press according to claim 1, further comprising: 4. The paper holding means (15, 55) is provided on the track surface (14, 50a) of the transport means (11, 50) at least as many as the printing drums (9, 51). The multicolor printing press according to claim 1, 2 or 3, wherein: