JP2003089479A - Printing equipment - Google Patents

Abstract

(57) [Summary] [Problem] Two-color printing, full-color printing, or double-sided printing can be realized with a simple configuration, and two or four-color printing or two-sided printing can be performed by easily superimposing other colors on a one-color machine or a two-color machine. There has never been a simple and easy printing device capable of printing. A re-feeding device for feeding a single-sided printed sheet from a re-feeding tray to a printing section is provided. A claw member 34 capable of holding the leading end of the paper 39 and releasing the leading end of the single-sided printed paper 39a other than at the time of paper ejection; a toothed belt 33 to which the claw member 34 is fixed; Cams 55A and 55B that release drive of the cam 34
And a plurality of open / close locations for holding or releasing the leading end of the printing paper 3 or the single-sided printed paper 39a by the claw member 34, and a double-printing conveying and discharging means 49 for performing double-printing. And a double-sided printing conveying and discharging means 112 for performing double-sided printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing device,
More specifically, it relates to a printing apparatus such as an offset printing machine or a stencil printing machine that uses a printing plate.

[0002]

2. Description of the Related Art As a printing apparatus capable of relatively simple printing, a stencil printing machine using a master (printing plate), an offset printing machine using a printing plate, etc. are known. For example,
In FIG. 18 of Japanese Patent Laid-Open No. 10-315601, a plate cylinder (a plate drum or a printing drum) having a plate-made master, which has been plate-formed corresponding to a color image, is wound around the outer peripheral surface, is arranged in a substantially horizontal sheet conveying direction. Printing paper (sheet-like sheet-like recording medium such as sheets, transfer materials, recording materials, etc.) printed by the plate cylinders, which are arranged in the space between the plate cylinders and are arranged upstream between the plate cylinders in the paper transport direction. Hereinafter, the same) is arranged. An stencil printing apparatus capable of multicolor printing by one sheet feeding operation is provided by disposing an intermediate conveying device that conveys to the plate cylinder located on the downstream side in the sheet conveying direction. Is disclosed (hereinafter, “first technology”)
That).

Further, for example, in JP-A-4-105984 and JP-A-2000-198262, there is a backing roller or a paper cylinder (impression cylinder or paper gripping cylinder) having a diameter substantially the same as the outer diameter of the printing drum (plate drum). ) And a multicolor stencil printing device are disclosed. In particular, as shown in FIG. 7 of Japanese Patent Application Laid-Open No. 4-105984 and FIG. 1 of Japanese Patent Application Laid-Open No. 2000-198262, around a single backing roller and a paper cylinder (impression cylinder or paper gripping cylinder). In addition, in the case of a multicolor stencil printing machine in which multiple printing drums are arranged, there is no transfer of paper to the pressing means such as other paper gripper cylinders, so it is excellent in paper transportability and small size paper is used. However, there is an advantage that it is easy to synchronize with each printing drum, it is easy to print, and double-sided printing can be done with a relatively simple configuration.
"Second technology").

On the other hand, in a printing apparatus such as an offset printing machine, a so-called chain delivery method has been conventionally used as a method of transporting printing paper. This is equipped with a claw member (holding means) for sandwiching the printing paper between a pair of chains or toothed belts which are arranged substantially parallel to each other, and which holds the leading edge of the printing paper by the pawl member. It is to be transported. The chain delivery system is generally used to receive a printed printing sheet and convey it to a sheet discharging position, as described in JP-A-11-334037. A pawl member that is always closed by the force of a spring is opened and closed by a cam at the print paper receiving position to clamp the print paper, and at the paper ejection position, the pawl member is also opened and closed by the cam to release the print paper. It is configured to do. BACKGROUND ART Transferring an image onto a printing sheet in a printing apparatus has heretofore been carried out by providing a claw for sandwiching the printing sheet on the impression cylinder, winding the printing sheet around the outer peripheral surface of the impression cylinder, and pressing the printing drum.

Japanese Patent Publication No. 2983661 discloses a stencil printing apparatus for multicolor printing which employs a chain delivery system in an image transfer area. A claw member is provided on a chain that runs from upstream to downstream of the transfer regions (printing sections) of a plurality of printing drums with different ink colors, and the claw member holds the printing paper and conveys it while pressing the printing paper with the press roller. The image is transferred sequentially by pressing it on the printing drum.

When the chain delivery system is adopted in the image transfer area, it is difficult to obtain the transfer timing with respect to a plurality of printing drums (plate drums) with high accuracy as compared with the impression cylinder system, and the image shift occurs due to the shift of the transfer position. easy. Due to such problems peculiar to the chain delivery system, the impression cylinder system is still mainstream in offset printing machines and the like.

In the case of the chain delivery type sheet conveying device, since the printing sheet is not delivered, there is an advantage that highly accurate transfer without variations in the resist and color misregistration prevention performance necessary for image formation can be expected. In particular, in the system in which the front end portion of the printing paper is nipped by the nail member immediately after the paper is fed from the paper feeding device, that is, before printing, and the printing paper is conveyed by the nail member until the ejection, The advantage is remarkable (hereinafter, referred to as “third technology”).

[0008]

However, in the first technique, since the intermediate conveying device is arranged between the plate cylinders, the sheet can be delivered to the pressing means such as another press roller. It is necessary and requires special measures to secure the paper transportability, and there is a problem that it is difficult to prevent the color misregistration necessary for highly accurate transfer of a printed image without variations in resist and image formation. . Further, when using a small size paper (paper short in the paper transport direction), there is a limitation in the arrangement interval of the adjacent plate cylinders, and therefore, the entry synchronization from the first color plate cylinder to the second color plate cylinder is taken, for example. However, there is also a problem that it is difficult to obtain the print image position accuracy for the second and subsequent colors.

In the second technique, when a plurality of printing drums are arranged around the rotation direction of a single paper holding cylinder, an ink supply roller (for supplying ink to the inner peripheral surface of each printing drum). Since the intermediate pressing roller 118) has various arrangement positions in the rotation direction with respect to the rotation center of the print drum in each print drum, it has various positions in the rotation direction with respect to the rotation center of the print drum. The position of the doctor roller also changes even if the printing drums have the same roller arrangement, which causes a problem that the ink pool cannot be formed at a stable position in some cases. As a result, there is a problem in that the ink cannot be retained in the ink reservoir, normal printing cannot be performed, and the ink leaks.

Including the first to third techniques, at least one plate drum, which is arranged side by side in the sheet conveying direction with a space therebetween, holds the printing plate, and ink is applied to the printing plate on the plate drum. A printing device having a developing device for supplying, a paper transport device for transporting print paper toward the printing portion of the plate drum, and a first paper feed device for feeding the print paper to the paper transport device, and a printing device At least one plate drum that holds the plate, a developing device that supplies ink to the printing plate on the plate drum, and an ink image formed on the printing plate that is provided so as to face the plate drum and be in contact therewith are transferred. Transfer drum, a paper transporting device for transporting the print paper to the transfer drum, a first paper feeding device for feeding the print paper to the paper transporting device, and a printing unit formed by pressing the transfer drum. Paper transport device In a printing apparatus having a transfer member that presses a print sheet that is further conveyed to a transfer drum, a storage unit that temporarily stores the printed sheet from the sheet conveying apparatus is provided, and the printed sheet is again stored from the storing unit. A second paper feeding device that feeds toward the printing unit is provided, and an opening / closing position for pinching / holding or releasing the leading edge of the printing paper by a claw member (holding means) of the paper transportation device is provided around the paper transportation device. There has never been a technical idea to change the positions of the cams for clamping and releasing the claw members depending on the opening / closing position for each purpose.

Therefore, the present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide a printing apparatus using a printing plate, which can solve the above-mentioned problems. When printing two or more colors on a sheet-type sheet recording medium or performing double-sided printing, double printing, full-color printing or double-sided printing can be realized with a simple configuration. It is to realize a printing device which is effective when two-color printing, four-color printing or double-sided printing is easily performed by overlapping other colors. Further, it is intended to realize a printing device capable of easily and automatically printing a full-color high-quality printed image when deployed on a two-color machine, and capable of performing eight-color printing on a four-color machine. . in addition,
The advantages of the chain delivery type paper transport device can be fully utilized, the ink reservoir can be formed in a stable position with a simple arrangement of the developing device, ink does not leak, and the installation area of the printing device is advantageous and convenient. It is also an object of the present invention to provide a printing device having high performance and low cost.

[0012]

In order to solve the above problems and to achieve the above objects, the inventions described in each claim adopt the following characteristic means and configurations. According to a first aspect of the present invention, at least one plate drum that holds the printing plate, a developing device that supplies ink to the printing plate on the plate drum, and a printing sheet toward the printing unit of the plate drum are provided. In a printing apparatus having a paper transporting device for transporting and a first paper feeding device for feeding printing paper to the paper transporting device, storage means for temporarily storing the printed paper from the paper transporting device is provided. It is characterized by further comprising a second paper feeding device for feeding the printed paper from the storing means to the printing unit again.

According to a second aspect of the present invention, at least one plate drum holding the printing plate, a developing device for supplying ink to the printing plate on the plate drum, and the plate drum can be contacted in opposition to each other. Transfer drum to which the ink image formed on the printing plate is transferred, a paper transport device for transporting the print paper to the transfer drum, and a first paper feed device for feeding the print paper to the paper transport device In a printing device having a device and a transfer member that presses against the transfer drum to form a printing unit and presses the printing paper conveyed by the paper conveying device against the transfer drum, It is characterized by comprising a storage means for temporarily storing printed sheets, and a second paper feeding device for feeding the printed sheets from the storing means to the printing section again.

The invention according to claim 3 is the invention according to claim 1 or 2.
In the printing apparatus described above, the paper transporting device is capable of holding the leading end of the printing paper other than when the paper is being fed and releasing the leading end of the printed paper when the paper is not being ejected. A belt which is fixed between the pulleys so as to fix the holding means and run between the pulleys so that the printing section runs from the upstream side to the downstream side thereof; and a driving means which drives the holding means. It has a plurality of opening / closing portions for holding or releasing the front end of the printing paper by the holding means, and is provided between the paper transporting device and the storage means, and is provided twice for two-time printing. It is characterized in that it is provided with a conveying and discharging means for printing and / or a conveying and discharging means for double-sided printing for performing double-sided printing.

According to a fourth aspect of the present invention, in the printing apparatus according to the third aspect, the drive means includes a cam device having a cam, and the cam which drives the holding means in accordance with each opening / closing position. Is provided with a cam position changing means for changing the position.

The invention according to claim 5 is the invention according to claims 1 to 4.
In the printing apparatus according to any one of the items 1 to 3, each of the plate drums includes a plurality of the developing devices, and a second printing and / or a double printing are performed in association with a feeding operation of a printed sheet by a second sheet feeding device.
Alternatively, full-color printing and / or double-sided printing can be performed.

According to a sixth aspect of the present invention, in the printing apparatus according to the fifth aspect, the printed sheet is supplied to the printing section and the second sheet feeding device by cooperation of the sheet feeding device and the second sheet feeding device. It is characterized in that it is conveyed a plurality of times to and from a paper apparatus and printed, and the plurality of times of printing is controlled not only during single-sided printing but also during double-sided printing.

The invention according to claim 7 is the invention according to claim 5 or 6.
In the printing apparatus described above, the developing device contains inks that are partly the same or different in color depending on the application.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention including examples with reference to the drawings (hereinafter, simply referred to as "embodiments")
Will be explained. Regarding each embodiment and the like, regarding components such as members and components having the same function and shape,
The description will be omitted after the description is given once by giving the same reference numerals. In order to simplify the drawing and the description, even the constituent elements that should be represented in the drawing may be appropriately omitted without special description in the drawing.

First, a schematic configuration of an offset printing machine 1 as a printing device will be described with reference to FIGS.
The offset printing machine 1 can print with two colors of ink.
It is an example of a color printing machine. As shown in FIG. 1, the offset printing press 1 includes a printing press main body 2 that forms the framework of the offset printing press 1 and two printing stations 3A that are arranged side by side in a substantially horizontal direction at intervals in the paper transport direction X. 3B, and a belt-conveying type paper conveying device 5 that is provided below the printing stations 3A and 3B and that conveys the printing paper 39 or the one-side printed paper 39a toward the printing units 13A and 13B of the printing stations 3A and 3B. , This paper transport device 5
A first sheet feeding device 4 (hereinafter, simply referred to as "printing device 4") provided on the right side of the sheet feeding device 5 for feeding the printing sheet 39 to the sheet feeding device 5, and the single-side printed sheet 39 from the sheet feeding device 5
Re-feeding tray 4 as a storing means for temporarily storing a
And a re-feeding device 40 serving as a second paper-feeding device for feeding single-side printed paper 39a from the re-feeding tray 44 toward the printing units 13A and 13B again, and finally printing Discharge roller pair 36 for conveying and discharging the printing paper 39 of
And a discharge tray 6 as a discharge tray for stacking the final printed printing paper 39 conveyed and discharged by the discharge roller pair 36.

The printing station 3A has, as shown in FIG. 1, a plate drum 7A having a rotary support shaft 14A for winding and holding a printing plate 8A having heat-sensitive and water-repellent properties shown in FIG. 2, and this plate drum 7A. Writing device 9A for writing on the printing plate 8A on 7A based on image information, and two developing devices 10 for supplying ink to the printing plate 8A on the plate drum 7A.
A, 10B, a transfer drum 11A that is provided so as to face the plate drum 7A so as to be in contact therewith and to which the ink image formed on the printing plate 8A is transferred, and a transfer drum 11A after the transfer.
And a cleaning device 12A for cleaning the surface of the.

As shown in FIG. 2, most of the printing plate 8A is contained in the plate drum 7A. Printing plate 8
By the unwinding by the unwinding shaft 18A that rotates following the movement of A, a part of the unwinding shaft 18A selectively moves.
A new printing plate 8A is wound around A and is wound around the plate drum 7A. The plate drum 7A is configured so as to be able to come into contact with and separate from the transfer drum 11A by a drum contacting / separating unit (not shown). The plate drum 7A and the transfer drum 11A are arranged in a substantially vertical direction. The printing plate 8A is a thermal plate-making plate made of a material having both heat sensitivity and water repellency. The water repellency when heated is lost from the characteristics of the material, and the water repellency is reversed, that is, hydrophilic. It has a changing nature. Note that the printing plate 8A is not limited to this, and may have a property opposite to the above.

The developing devices 10A and 10B are the plate drum 7A.
Are arranged substantially symmetrically with respect to the center (center line of the plate drum 7A extending in the vertical direction). The printing station 3B on the downstream side in the paper transport direction X also has the same configuration, and the developing device 10A corresponds to the developing device 10C arranged around the plate drum 7B, and the developing device 10B surrounds the plate drum 7B. The arranged developing device 10D corresponds to this. Inks of different colors are stored in the developing devices 10A, 10B, 10C and 10D, respectively. Incidentally, the developing device 10A
Is also called an ink supply device.

The transfer drum 11A has a rotary support shaft 15A and a recess 16A as an escape for the claw member 34 of the sheet conveying device 5. Transfer drum 11
A transfer blanket (not shown) for transferring the ink image formed on the printing plate 8A is wound around the outer peripheral surface of A. The outer diameter of the transfer drum 11A is equal to that of the plate drum 7.
The size is the same as that of A, and when the plate drum 7A makes one revolution, the transfer drum 11A also makes one revolution exactly. The transfer drum 11A always occupies a fixed position and is not displaced, and is rotationally driven in the clockwise direction indicated by an arrow in FIG. 1 by an electric motor (not shown) as a driving unit (driving source). The plate drum 7A is connected to the electric motor via a rotation transmitting means such as a belt and a gear, and is rotationally driven in the counterclockwise direction indicated by an arrow in FIG.

The cleaning device 12A includes the transfer drum 1
1A, a cleaning web 20A that can come into contact with the surface of the transfer blanket, a web unwinding roller 23B that is formed by winding the cleaning web 20A and that can unwind the cleaning web 20A, and the unwinding cleaning web 20A that is wound around the transfer drum 11A. It has a cleaning roller 21A which can be brought into and out of contact with the surface of the transfer blanket, a web winding roller 22A which winds up the cleaned cleaning web 20A, and the like.

The writing device 9A, which is also called a plate making device, is a laser plate making device equipped with a laser, and writes according to the image to be printed on the printing plate 8A on the plate drum 7A by the heat of the laser beam. It is a well-known thing to do.

The other printing station 3B has the same structure as the above-mentioned printing station 3A,
The description is omitted by substituting the English letter B for the alphabetical letter A of the code corresponding to the Arabic numeral of the printing station 3A. However, the developing device 10A contains cyan (C) ink, the developing device 10B contains yellow (Y) ink, and the developing device 10C contains magenta (M) ink.
The main difference lies in that the developing device 10D contains black (Bk) ink.

The printing unit 13 is pressed against the transfer drums 11A and 11B so as to face and face the transfer drums 11A and 11B.
The printing paper 39, which is provided to form A and 13B and is conveyed by the paper conveying device 5, transfers the printing paper 39 to each transfer drum 11A,
Transfer roller 29 as a transfer member pressed against 11B
A and 29B are provided respectively. Further, in the vicinity of the downstream of the transfer drums 11A and 11B in the paper transport direction X,
Paper separation rollers 35A and 35B are provided to prevent the printing paper 39 from rolling up on the transfer blankets of the transfer drums 11A and 11B, respectively. The transfer rollers 29A and 29B are also referred to as press rollers, and are respectively transferred to the transfer drums 11A and
11B is pressed against the printing paper 39 via the printing paper 39 to selectively occupy a printing position where the ink image is transferred and a non-printing position separated from the printing position.

As shown in FIGS. 1 and 12, the paper feeding device 4 includes a paper feeding tray 27 provided with a paper feeding table (not shown) which stacks printing paper 39 and can be raised and lowered, and the printing paper 39. It has a first sheet feeding means for sequentially separating the sheets one by one from the top and feeding them in the sheet feeding direction 109.

The first sheet feeding means is formed of a sheet feeding roller 28 which is driven to rotate in a clockwise direction shown by an arrow in FIG. Separation pad 26 shown in a satin pattern in FIG.
And a biasing means such as a spring (not shown) that biases the separation pad 26 in a direction in which it comes into contact with the paper feed roller 28. A pair of side fences (not shown) that can move to the front and back sides of the paper surface of FIG. 1 for aligning both side edges of the printing paper 39 are also arranged on the paper feeding table. The positional accuracy in the direction can be easily ensured.

In this paper feeding device 4, the offset printing machine 1
By supplying the printing paper 38 at any time during the operation of
The paper feeding operation is automatically performed so that so-called tandem paper feeding can be performed without interruption. As a preferable example of tandem paper feeding in a printing apparatus, for example, Japanese Patent Laid-Open No. 11-240630 proposed by the applicant of the present application,
JP-A-11-240631, JP-A-11-24063
2, JP-A-11-292306 and JP-A-11-29.
Examples thereof include those disclosed in Japanese Patent No. 2312.
In these paper feeding devices, the above-mentioned tandem paper feeding and non-tandem paper feeding, which can automatically feed paper without interrupting the paper feeding operation, can be switched and used. In FIG. 1, the paper feed tray 27 and the printing paper 39 are divided into two by a chain double-dashed line in order to represent the outline of the tandem paper feeding, and separate trays and printing paper 39 are shown. Is possible.

Below the sheet conveying device 5, due to a peculiar opening / closing operation of a claw member 34, which is a component of the sheet conveying device 5 which will be described in detail later, double-printing or full-color printing of the sheet 39a with one side printed is performed. Alternatively, a temporary standby-type sheet re-feeding device 40 that allows sheet re-feeding for double-sided printing is provided. As shown in FIGS. 1 and 4, the sheet re-feeding device 40 includes the above-mentioned cassette type sheet re-feeding tray 44, and the single-side printed sheet 39 accommodated in the sheet re-feeding tray 44.
a and a bottom plate 45 that is urged upward so that the one-side printed paper 39a at the leading end of the paper feeding side is brought into contact with the paper feeding roller 46 by a spring or the like, and the uppermost one-side printed sheet on the bottom plate 45. Paper 39a is separated sheet by sheet and re-feed direction 1
It is mainly composed of a second paper feeding means for re-feeding paper to the paper 18.

The second paper feed means has a paper feed roller 46 rotated by a drive means (not shown) in the counterclockwise direction shown by an arrow in FIG. A separation pad 47a formed of a member and shown in a satin pattern in FIG.
6 is mainly configured by an urging unit such as a spring (not shown) that urges the member 6 in a direction in which the member 6 abuts. As shown in FIG. 4, the separation pad 47 a is fixed to the pad holder 47.
The pad holder 47 is swingably supported clockwise and counterclockwise about a support shaft 48 that is planted and fixed on the inner wall of the refeed tray 44, and the separation pad 47a is supported by the spring. It is biased so as to come into contact with the paper feed roller 46. The pad holder 47 is also formed with a front wall 47b that abuts and aligns the leading ends of the single-side printed sheets 39a stacked on the bottom plate 45.

Further, on the bottom plate 45, a pair of side fences (not shown) which are movable to the front side and the back side of the paper surface of FIG. The position accuracy in the width direction of the single-side printed paper 39a can be easily ensured. In the present embodiment, a pair of side fences (not shown) on the sheet feeding table in the sheet feeding device 4, a sheet conveying device 5 described in detail later, and a pair of side fences (not shown) on the bottom plate 45. ) And printing paper 39 or paper 39 that has been printed on one side
a is a paper feeding direction 109 shown in FIG. 12, a paper carrying direction X by the paper carrying device 5, a second paper discharge carrying direction 111 or a third paper discharge carrying direction 113 shown in FIG.
By being able to move on the common center line over 18, the printing paper 39 or the single-side printed paper 39a is printed.
Since it is easy to secure the positional accuracy in the width direction, it is mainly configured to control only the position of the printing paper 39 or the one-side printed paper 39a in the flow direction.

In this way, the re-feeding device 40 successively carries in, for example, the single-side printed sheets 39a from the paper transporting device 5 to the re-feeding tray 44 one after another in succession, and the carrying-in of the predetermined number of sheets is completed. During standby, the single-side printed sheet 39a is re-fed and the toothed belt 33 in the sheet conveying device 5 is re-fed.
The upper claw member 34 again holds the front end of the paper 39a having one side printed, and the paper 39a is re-conveyed to the printing units 13A and 13B to transfer the ink image again.

Although the well-known structure is not shown in order to simplify the drawing, the paper feed roller 28 is provided in the paper conveyance path between the paper feed roller 28 and the driven pulley 32 in FIG. After temporarily stopping the printing paper 39 pulled out by the paper and the one-side printed paper 39a fed from the re-feeding device 40 to correct the skew displacement and the like, the paper is transferred to the claw member 34 of the paper transporting device 5 at a predetermined timing. It should be noted that a pair of registration rollers (not shown) as registration means for feeding the printing paper 39 is also preferably arranged.

The paper discharge tray 20 has a pair of side guides 38 that are displaced by driving means (not shown) so as to approach and separate from each other in the direction perpendicular to the paper surface of FIG. The side guide pair 38 has a function of aligning both side edges of the final printed sheet 39 that is conveyed and discharged.

The image forming principle of the offset printing machine 1 is based on substantially the same principle as that of a normal offset printing machine. The image forming principle will not be described in detail in the operation to be described later, but an adhesive oily ink or the like is used, and the plate materials of the printing plates 8A and 8B are of a waterless type and have water repellency and hydrophilicity. A printer using the above-mentioned heat-sensitive water-repellent material that utilizes the difference is provided with a waterless planographic type plate making device (writing devices 9A, 9B). Of course, it goes without saying that the present invention can be applied to a conventional offset printing machine with water.

Next, an outline of the printing operation by the offset printing machine 1 will be described. The offset printing machine 1 can continuously and automatically perform steps such as a document reading step / plate making step → developing step → intermediate transfer step → final sheet transfer step → cleaning step. Here, a normal two-color single-sided printing operation for forming a two-color printed image only on one surface (upper surface) of the printing paper 39 (hereinafter, referred to as “normal single-sided printing operation”) will be described. Regarding the double-printing operation and the double-sided printing operation, the developing devices 10A to
The configuration around 10D, the sheet conveying device 5, and the re-feeding device 40 will be described in detail later.

Before the first original reading process and plate making process, the transfer drum 11 is transferred to the plate drums 7A and 7B.
The A, 11B and the cleaning devices 12A, 12B are in a standby state because they are separated by the drum contacting / separating means and the cleaning roller contacting / separating means (not shown). Developing device 10
A, 10B, 10C and 10D are contacting / separating means 97 described later.
By A, 97B, 97C, 97D, each plate drum 7A,
It stands by in a state of being separated from the outer peripheral surface of 7B. Since the same operation is performed in each of the printing stations 3A and 3B, the printing station 3A will be described below as a representative unless otherwise specified.

When the operator presses the start switch on the operation panel (not shown), the document is read by the scanner unit (not shown). In one of the printing stations 3A, writing is performed on the printing plate 8A wound around the plate drum 7A by the writing device 9A based on the read image signal. That is, image data to be written in the printing plate 8A (also referred to as print data, hereinafter referred to as "image data") is an electric / electronic circuit (A / D) not shown.
It is processed by an (analog / digital) conversion device, an image processing device, etc. and sent to a laser device (not shown), which is converted into a laser beam and the image data is written on the printing plate 8A. The printing plate 8A in the portion where the image data is written by the laser beam loses the water repellency of its surface due to the heat, and becomes hydrophilic (the opposite case is also possible). The portion written by the laser beam becomes hydrophilic, and sticky oily ink can be attached.

Thus, the illustrated example shows an example using the recent DI (Direct Imaging) technique for making a printing plate on a plate drum. The image data is not limited to the one corresponding to the original from the scanner unit, and for example, the image data from a personal computer is photothermally converted by the laser device and is applied to the printing plate 8A on the plate drum 7A. You can also write it. in this way,
In the printing market, the CTC (Computer To Cylinde
r) is the newest printing technology. Such a plate-making method can reproduce image data with extremely high positional accuracy in the printing machine, and is far superior to the conventional plate-making method in which a printing plate made outside the printing machine is mounted on the printing machine. It is simple and highly accurate.

When the plate making is completed, the selected one of the developing devices 10A and 10B containing the waterless ink having an adhesive offset, that is, the plate 8A for printing is prepared.
The developing device 10A accommodating the ink of the color to be developed (here, cyan) is brought into pressure contact with the plate drum 7A, and the ink adheres to the hydrophilic part of the image data part of the plate 8A for plate making. become. The contact operation of the developing devices 10A and 10B will be described later.

In the printing station 3A, when necessary ink is attached to the entire printing plate 8A, that is, when the development is completed, the plate drum 7A is transferred to the plate drum 7A without stopping the development process of the selected developing device 10A. The drum 11A is controlled so as to come into pressure contact with it. As a result, the ink attached to the printing plate 8A on the plate drum 7A according to the image data is transferred to the transfer blanket on the transfer drum 11A, and an ink image is formed on the transfer blanket.

In the state where the ink image is transferred to the transfer drum 11A, the uppermost printing paper 39 on the paper feeding tray 27 is fed in the paper feeding from the paper feeding device 4 while the timing with the ink image is planned. The paper feed roller 29 and the separation pad 26 cooperate to separate and feed the sheets one by one. At this time, an electric motor (not shown) forming the sheet conveying device 5 is driven so that the toothed belt 33 forming the sheet conveying device 5 rotates at a predetermined linear velocity (sheet conveying speed). The printing paper 39 is sent at a timing synchronized with the opening operation (described later) of the claw member 34 of the paper transporting device 5, and the leading end of the printing paper 39 is clamped by the claw member 34.

When the printing paper 39 is nipped by the claw members 34, it is carried in the paper carrying direction X by the rotation of the toothed belt 33, and first, the transfer roller 29A is displaced upward by the operation of the contact / separation displacement means (not shown). By doing so, the printing paper 39 is pressed against the transfer drum 11A, and the cyan ink image carried on the transfer drum 11A is transferred.

The printing paper 39 on which the image is formed is separated by the paper separating roller 35A provided in the vicinity of the transfer portion downstream of the transfer drum 11A, is prevented from being wound around the transfer drum 11A, and is conveyed by the paper conveying device 5. It Such steps and operations are similarly performed in the downstream printing station 3B, and the printing paper 39 on which the image is carried by the paper carrying device 5 is transferred to the transfer drum 11B.
And the transfer roller 29B enter the printing portion (nip portion) 13B at the timing when the ink images match.

As a result, the downstream printing station 3
At B, the magenta ink images of the second color carried on the transfer drum 11B are superimposed and transferred at the above timing, and desired multicolor (here, two colors) printing is performed. The printing paper 39 on which the two-color printed image is formed is separated by the paper separating roller 35B provided in the vicinity of the transfer portion downstream of the transfer drum 11B, is prevented from being wound around the transfer drum 11B, and is conveyed by the paper conveying device 5. Then, the claw member 34 is released by a releasing operation (described later), guided and conveyed toward the paper discharge tray 6 by the paper discharge roller pair 36, and stacked while being aligned by the side guide pair 38.
The detailed configuration and operation of the sheet conveying device 5 will be described later. When the printing of the predetermined number of sheets is completed, the contacting / separating means 97A, which will be described later,
By the operation of 97B, the developing devices 10A and 10C are separated from the plate drums 7A and 7B and occupy their initial positions. At the same time, the plate contact drums 7A and 7B are transferred to the transfer drums 11A and 11B by operating the contact / separation displacement means.
Occupy their respective initial positions apart from.

When these separating operations are performed, the cleaning roller 21A of the cleaning device 12A moves so as to contact the transfer drum 11A by a pressing means (not shown), and the cleaning web 20A presses the transfer blanket surface (not shown) of the transfer drum 11A. To be done. The cleaning web 20A is sequentially fed out by a web unwinding roller 23A via a driving means (not shown), and is wound up by a web winding roller 22A, so that the ink remaining on the transfer blanket surface of the transfer drum 11A is wiped off.・ Cleaned. After the cleaning is completed, the pressing means moves the cleaning roller 21A to separate from the surface of the transfer blanket of the transfer drum 11A and occupies the initial position. Such steps and operations are similarly performed in the downstream printing station 3B.

After the cleaning step is completed, the winding shaft 17A shown in FIG. 2 is rotationally driven by the driving means, so that a new printing plate 8A for the next plate making is unwound onto the plate drum 7A. It is wrapped. And
The first step described above is performed again in the same manner, and the same printing step as the above-described step is performed based on the image data of the second sheet.

Next, the developing devices 10A and 10 shown in FIG.
B, 10C and 10D will be described in detail as a representative of the developing devices 10A and 10B with reference to FIG. In FIG. 3, the developing devices 10C and 10D and the contacting / separating means 97C and 97D shown in parentheses are arranged on the plate drum 7B side. As shown in FIG. 3, the developing device 10A includes a shaft 80A provided in the printing machine main body 2 shown in FIG.
And a developing casing 81A supported oscillatably in a clockwise direction and a counterclockwise direction with this as a fulcrum, an ink inking roller 83A rotatably provided on a shaft 82A in the developing casing 81A, and the developing casing. 81A
An ink replenishing roller 85A, which is rotatably provided on the inner shaft 84A and is located downstream of the ink replenishing roller 83A in the rotational direction of the plate drum 7A, and the developing casing 81.
An ink supply roller 87A provided on a shaft 86A in A and commonly contacting the ink inking roller 83A and the ink inking roller 85A to distribute ink to them, and a kneading roller 88A in contact with the ink inking roller 83A. And the ink supply roller 8A provided above the ink supply roller 87A.
It has an ink reservoir 89A having an opening (ink supply port) along the axial direction of 7A, an ink replenishing magazine 90A detachably provided above the ink reservoir 89A, and the like. The ink replenishing roller 83A and the ink replenishing roller 85A are also referred to as a developing roller 83A and a developing roller 85A.

The ink reservoir 89A is divided into a container shape by four side walls, and an upper surface facing the ink replenishing magazine 90A and a lower surface facing the ink supply roller 87A are opened. That is, the upper surface is the ink replenishing port from the ink replenishing magazine 90A, and the lower surface is the ink replenishing port for the ink replenishing roller 87A. A blade 91A as an ink film thickness regulating member for regulating the ink film thickness on the ink supply roller 87A is attached by a shaft screw 92A to a rear side wall 89Aa of the ink reservoir 89A on the downstream side in the rotation direction of the ink supply roller 87A. There is. The blade 91A is attached to the rear side wall 89A by the axial screw 92A at the central position in the axial direction of the ink supply roller 87A.
It is rotatably attached to a. That is, the ink supply roller 87A is provided rotatably in the direction in which the gap between the ink supply roller 87A and the ink supply roller 87A is changed with the central portion in the axial direction as a fulcrum. It has a so-called Yajiro Bay structure. As a result, the blade 91A comes into contact with the ink supply roller 87A with uniform pressure over the entire axial direction, and the ink film thickness also becomes uniform.

Since the blade 91A blocks the adhesive ink, it receives a great fluid resistance. In the present embodiment, the tip shape of the blade 34 is formed in a wedge shape in order to reduce the fluid resistance and make the film thickness regulating function of the blade 91A constant, simplifying the configuration, and extending the life. Other streamline types that reduce fluid resistance may be used.

On the other hand, the ink supply roller 87A is provided on the front side wall 89Ab on the upstream side in the rotation direction of the ink supply roller 87A.
The upper ink is allowed to rotate and return to the ink reservoir 89A, and the ink supply roller 8 is fed from the ink reservoir 89A.
A skirt member 93A is provided to prevent 7A from flowing out to the upstream side in the rotational direction. The skirt member 93A is formed of a flexible material, for example, a rubber sheet. The skirt member 93A allows the rotational reflux of the ink on the ink supply roller 87A, the thickness of which is regulated by the blade 91A, returning to the ink reservoir 89A.
Also, from the ink reservoir 89A to the ink supply roller 87A
Is provided so as to prevent outflow (backflow) to the upstream side in the rotation direction. The liquid-like display in the ink reservoir 89A and the ink replenishment magazine 90A indicates adhesive ink.

The developing device 10A is provided so as to be attachable to and detachable from the printing machine main body 2 shown in FIG.
It forms a unitized developing device unit. An upper guide member 94A and a lower guide member 95A for guiding attachment / detachment of the developing device 10A are provided on the printer body 2 side. These guide members 94A and 95A are fixed to the printer main body 2 side with a set screw 96. The unitized developing device 10A is inserted along the inner portion surrounded by the guide members 94A and 95A, and the shaft 80A is completely inserted into the shaft hole 81Aa, whereby the mounting of the developing device 10A is completed. Since the developing device 10A is detachable, even when performing special color printing using a special ink (special color ink) that is rarely used, the developing device 10 containing another special color ink is used.
All you have to do is replace A. In addition, in the printing machine main body 2,
As shown in FIG. 3, the developing device 10 is attached to the plate drum 7A.
A contact / separation unit 97A for contacting / separating A, that is, for contacting / separating the ink inking roller 83A and the ink inking roller 85A with respect to the plate drum 7A is provided. Contact / separation means 9
7A is a drive source (not shown), a drive shaft 98A to which the rotational drive force from the drive source is input, an eccentric cam 99A fixed to the drive shaft 98A, and a direction in which the developing casing 81A is brought into contact with the eccentric cam 99A. And a biasing means such as a spring (not shown) that constantly biases the power source. The eccentric cam 99A is
It is in contact with the outer wall surface of the developing casing 81A.

The ink replenishing roller 83A and the ink replenishing roller 85A are rubber rollers, and the shafts 82A and 84A for supporting them are not connected to a drive source and can rotate freely (driven). Ink supply roller 87
The shaft 86A supporting A is connected to a drive source (not shown) of the developing device 10A, and its rotation speed (peripheral speed) is controlled by control means (not shown). The developing device 10B also has the same configuration as the developing device 10A. Developing device 1
In 0B, the code A is simply changed to B, and the description thereof will be omitted.

However, as described above, the developing devices 10A, 1
Although 0B is provided substantially symmetrically with respect to the center of the plate drum 7A, not all its components have symmetry. That is, the ink replenishing rollers 83A, 85A and the ink supply roller 87A, and the ink replenishing rollers 83B,
85B and the ink supply roller 87B are arranged substantially symmetrically, but their rotation directions are the same. This is because it is arranged on one plate drum 7A, and it is necessary to match the rotation direction of the plate drum 7A. Since the ink supply rollers 87A and 87B rotate in the same direction, the ink reservoirs 89A and 89B, the blades 91A and 91B, and the skirt members 93A and 93B have the same arrangement so that the functions of the developing devices 10A and 10B are the same. Has become. As described above, the asymmetry of some of the components contributes to the commonality of the components and the cost reduction in the substantially symmetrical arrangement configuration, and the function can be unified.

FIGS. 1 and 3 show the state during development, and the developing devices 10A and 10B are the contacting / separating means 97A and 97B.
Is pressed and brought into contact with the plate drum 7A. That is, the ink inking rollers 83A and 85A and the ink inking rollers 83B and 85B are in pressure contact with the plate drum 7A. In practice, when two printing plates for two plates are wound around the plate drum 7A, for example, when the plate drum 7A is a drum having a size of one plate of the maximum original size of the offset printing machine 1, In the case of a so-called 1 × cylinder, the developing devices 10A and 10B
One of them is selected according to the color of the printing plate on which the plate has been made, and pressed from the retracted position (non-developing position).

That is, for example, when the developing device 10A is selected, only the contacting / separating means 97A is driven to press the developing device 10A against the plate drum 7A, and the developing device 10B is provided with a biasing means such as the spring. The retracted position is maintained by the power. In the developing device 10A, at the time of non-developing, the contacting / separating means 97A is driven by the control means (not shown) to separate the developing device 10A from the plate drum 7A. Eccentric cam 99
When A rotates in the direction of the arrow (or in the opposite direction), the developing device 10A swings and displaces around the shaft 80A in the direction away from the plate drum 7A by the urging force of the urging means.
As a result, the ink inking roller 83A and the ink inking roller 85A are separated from the plate drum 7A. Developing device 10
The same applies to B. In the case of the 1 × cylinder, the toothed belt 33 serving as a sheet conveying belt has a circumference of twice the outer diameter of the transfer drum 11A. Printing station 3A,
Since there are four color inks in 3B, the developing device 1
It is possible to perform four types of two-color printing without replacing 0A, 10B, 10C, and 10D.

When two plates for printing are wound around the plate drum 7A, for example, when the plate drum 7A is a drum having a size of two plates of the maximum original size of the offset printing machine 1, that is, In the case of a so-called double cylinder, the two developing devices 10A and 10B are controlled so as to contact the plate drum 7A during printing of the corresponding printing plates. The same applies to the printing station 3B. In the case of a double cylinder, the toothed belt 33 has a triple circumference, and the printing paper 3
Full-color printing is possible by transporting 9 or the like twice.

Below, the developing devices 10A, 10B, 10
The developing functions of C and 10D will be described in detail. In addition,
Since the developing function is common, the developing device 10A will be described as a representative. From the ink reservoir 89A to the ink supply roller 8
The ink supplied onto 7A is regulated to have a constant thickness by the blade 91A, and is substantially evenly distributed to the ink inking roller 83A and the ink inking roller 85A. This allows
The image surface on the printing plate, to which the ink has been supplied by the ink inking roller 83A on the upstream side of the plate drum 7A, is again supplied with approximately the same amount of ink by the ink inking roller 85A on the downstream side. That is, the two-step development is performed under the condition that the ink amounts are supplied in the same amount.

Generally, the rotational speed is controlled so that the peripheral speed of the ink supply roller 87A and the peripheral speed of the plate drum 7A are the same. When the adhesive ink is used, the contact pressure of the ink inking rollers 83A and 85A with respect to the plate drum 7A is not the same as the contact pressure with the ink supply roller 87A. Therefore, the formed nip is different, and the ink feed rollers 83A and 85A free from the drive source rotate in a complicated manner. According to experiments by the present inventors, when the peripheral speed of the ink supply roller 97A is slightly higher than the general speed, the peripheral speeds of the ink inking rollers 83A and 85A become the same as the peripheral speed of the plate drum 7A. I knew that. It is considered that this is because the difference in the nip formation and the friction between the rollers due to the interposition of the adhesiveness of the ink are complicated. In the present embodiment, based on this experimental fact, the ink supply roller 87A is rotationally driven so that the peripheral speed thereof is slightly higher than the peripheral speed of the plate drum 7A. A data table of the relationship between the type of ink (adhesiveness: viscosity) and the number of revolutions obtained in advance by experiments or the like is stored in the storage means of the control means (not shown), and the ink supply roller is automatically set according to the type of ink. The rotation speed of 87 A may be set.

The ink inking rollers 83A and 85A are formed so that their outer diameters are slightly different from each other. Ink is transferred from the ink replenishing rollers 83A and 85A to the plate drum 7A, and even if the ink replenishing rollers 83A and 85A come in contact with the ink supply roller 87A again, the image portion is solid and the ink consumption is large. The ink adhesion is very saturated and the ink does not get wet. Therefore, a so-called ghost may occur and print image quality may be deteriorated. When the outer diameters of the ink replenishing rollers 83A and 85A are made different, the ink is not replenished to the image due to the difference in the circumferential length, and the ink removed portions of the ink replenishing rollers 83A and 85A, that is, The parts where ink is supplied to the image complement each other, and the ghost problem can be prevented. In the present embodiment, speaking in terms of an example, the ink inking roller 8
The outer diameter of 3A is about 32 mm, and the outer diameter of the ink inking roller 85A is about 30 mm.

The ink replenishing magazine 90A is used in the developing device 1.
0A is detachable, and an ink pushing-out means (not shown) for dropping ink to the ink reservoir 89A is provided inside. When ink in the ink replenishment magazine 90A runs out, a new ink replenishment magazine 90A
Exchanged for.

As described above, in this embodiment, by providing a plurality of developing devices 10A to 10D, it is possible to obtain a high-quality color printed image simply and simply with high accuracy. In a two-color machine such as the offset printing machine 1 according to the present embodiment, inks such as cyan and magenta, which are usually process colors, are simply used to print what can be sufficiently printed with two colors, or special colors. It is also possible to prepare a higher level of ink by using the above ink. In a practical example,
It is often used for leaflet printed materials such as newspapers.

Next, with reference to FIGS. 1, 4, 10, and 11, the structure and function of the re-feeding device 40 will be described in detail. 1, 4, 10 and 1 are provided between the sheet conveying device 5 and the re-feed tray 44 of the re-feed device 40.
As shown in FIG. 1, the claw member 3 is used to perform double-press printing and the like.
Transporting and discharging means 49 for double-printing, which transports and discharges the single-side printed sheet 39a released from No. 4 to the re-feed tray 44.
Then, the double-sided printing transport discharging unit 112 transports the single-side printed sheet 39a released from the claw member 34 for double-sided printing to the re-feed tray 44, and temporarily stores it on the re-feed tray 44. The single-sided printed sheet 39 a is printed by the second sheet feeding means (the sheet feeding roller 46 and the separation pad 47).
A pair of re-feeding guide plates 118 for guiding in the re-feeding direction 118 through the re-feeding operation of a) are provided.

As shown in detail in FIGS. 4 and 10, the double-printing conveyance discharging means 49 is provided near the lower part of the drive pulley 31 constituting the paper conveying device 5 and re-feeds the single-side printed paper 39a. A guide plate 41 and a pair of guide plates 4 as guide means for guiding the sheet to be discharged to the tray 44.
3, 43, and a pair of feed rollers 42, 42 as a conveying / discharging means that is arranged between the guide plate 41 and the pair of guide plates 43, 43 to convey / discharge the one-side printed sheet 39a to the re-feed tray 44. Mainly consists of and. These guide plates 41, feed roller pairs 42, 42 and guide plate pairs 43,
Reference numeral 43 denotes two times for feeding the single-side printed paper 39a to the re-feed tray 44 with the printed image surface being the lower surface (back surface), as indicated by the double-dotted line with arrow in FIGS. A printing discharge passage 50 is configured.

As shown in detail in FIGS. 4 and 11, the double-sided printing conveying / discharging means 112 is provided in the vicinity of the driven pulley 32 constituting the sheet conveying device 5 in the vicinity of the driven pulley 32, and the single-side printed sheet 39a is re-feed tray. Guide plate 114 and a pair of guide plates 116, 116 as guide means for guiding the sheet to be discharged to 44, guide plate 114 and guide plate pair 11
Paper 39a, which has been printed between one side and the other side
Is mainly composed of a pair of feed rollers 115, 115 as a conveying and discharging means for conveying and discharging the sheet to the re-feed tray 44. These guide plates 114, feed roller pairs 115, 1
15 and the pair of guide plates 116, 116, the single-side printed sheet 39a is placed on the re-feed tray 44 with its printed image side facing up (front side), as indicated by the broken line with an arrow in FIGS. A double-sided printing transport discharge path 113 for sending in is configured.

Each feed roller pair 42, 42, 115, 11
5 is rotationally driven by, for example, separate stepping motors that are independent of each other as driving means, but is not limited to this.
It is of course possible to rotate and drive with a single stepping motor by interposing a rotary drive force connecting / disconnecting means such as an electromagnetic clutch on the feed roller pair 115, 115 side.

In this embodiment, both the double-printing conveyance discharging means 49 and the double-sided printing conveyance discharging means 112 are provided, but only one of them is provided depending on the necessity and the like. (See claim 3).

Next, with reference to FIG. 1 and FIG. 5 to FIG. 12, the structure and function around the sheet conveying device 5 will be described in detail. As shown in FIGS. 1, 5 and 8 to 12, the paper transporting device 5 is a single-sided device in which the leading end of the printing paper 39 fed from the paper feeding device 4 or the paper fed again from the paper refeeding device 40 is fed. Two claw members 34 as a holding unit having a function of receiving and holding the leading end of the printed sheet 39a and a function of releasing the pair, and a pair of downstream side (left side of the apparatus) in the sheet conveying direction X in the printing unit 13B. The drive pulleys 31 and 31 as toothed pulleys, the driven pulleys 32 and 32 as a pair of toothed pulleys located on the upstream side (right side of the apparatus) in the paper transport direction X in the printing unit 13A, and the two claw members 34 are provided. The pair of toothed belts 33 and 33 fixed between the drive pulleys 31 and 31 and the driven pulleys 32 and 32 while being fixed at predetermined intervals, and the claw members 34.
The cam 55 shown in FIGS. 8-12 for driving to release the
And cam devices 78AA and 78B provided with A and 55B.

The drive pulleys 31 and 31 are shown in FIGS.
(Not shown) as drive means via a rotary drive force transmission means such as a gear (not shown) fixed to the rotary shaft 52 shown in FIG. It is connected to an electric motor.

The claw member 34 has a detailed structure which will be described later.
It has an openable and closable structure that holds the leading edge of the printing paper 39 or the one-sided printed paper 39a while nipping it and carries it to the downstream side in the paper transport direction X and releases it for the next step. The toothed belts 33, 33 fix the two claw members 34, 34,
The two claw members 34, 34 and the claw member 34 are controlled by the transfer drums 11A, 11B and the like in speed, timing and the like.
Paper 39 sandwiched between papers or paper 39a that has been printed on one side
It has the function and structure to carry. As shown in FIGS. 1 and 5, drive pulleys 31, 31, driven pulleys 32, 32, toothed belts 33, 33 and two claw members 34, 34.
Are arranged in the same shape and in the same phase on the front side and the back side of the paper surface in FIG. 1, and hence the description of one will be omitted hereinafter.

Drive pulley 3 on the downstream side of the sheet conveying device 5
Do not flap the rear end of the printing paper 39 or the single-side printed paper 39a conveyed by the paper conveying device 5 for normal printing, double-press printing or double-sided printing in the vicinity of 1,31. Pressing rollers 37a and 37b for orderly conveying and discharging are rotatably supported by a side plate 100 and 100 shown in FIG.

As shown in FIG. 5, a pair of drive pulleys 3
The reference numerals 1 and 31 are fixed to a rotary shaft 52 arranged in parallel with the rotary support shaft 15A of the transfer drum 11A so that their tooth shapes coincide with each other in the rotary shaft direction of the transfer drum 11A. Similarly, the pair of driven pulleys 32, 32 are arranged so that their tooth shapes are aligned with each other in the rotation axis direction of the transfer drum 11A, with the rotation axis 54 arranged in parallel with the rotation axis 15A of the transfer drum 11A. It is fixed. The same applies to the transfer drum 11B side (hereinafter, the transfer drum 11A will be described as a representative). As a result, the tooth patterns of the toothed belts 33, 33 are also in phase with each other, and when fixing the claw member 34 to the toothed belt 33, it is easy to fix the toothed belt 33 in parallel with the rotation support shaft 15A of the transfer drum 11A. Become.

The drive pulley 31 is rotationally driven in the counterclockwise direction by the electric motor via the rotational drive force transmitting means, whereby the side close to the transfer drums 11A and 11B becomes the tension side of the toothed belt 33. There is. The toothed belt 33 is stretched between the drive pulley 31 and the driven pulley 32 so that the toothed belt 33 is substantially orthogonal to the rotation support shaft 15A and the traveling directions are substantially parallel to each other.
The side of the base member, which will be described later, of the claw member 34 includes the rotary shafts 52,
Both end portions of the toothed belts 33, 33 are fixed to the toothed belts 33, 33 so as to be substantially parallel to the toothed belt 54. In addition, in FIG. 5, the shape of the claw member 34 is shown in a simplified manner, and one of the two claw members 34 is omitted.

More specifically, the claw member 34
Is fixed to the pair of toothed belts 33, 33 so that the transporting posture of the printing paper 39 or the paper 39a having one side printed thereon is substantially tangential to the transfer drums 11A, 11B. The width W between the inner sides of the pair of toothed belts 33, 33 is set to be larger than the maximum width of the printing paper 39 orthogonal to the paper transport direction X. That is, the width W between the inner sides of the pair of toothed belts 33, 33 is set to be larger than the maximum width of the printing paper 39 that can be printed by the offset printing machine 1, whereby the width of the claw member 34 is set to the printing paper 39. It is designed to be larger than the width of.

Both ends of the rotary shaft 52 of the drive pulley 31 are
The bearing 51 is supported by the bearing 51, and the bearing 51 is fixed to the side plate 100 fixedly provided on the printer body 2 side. Reference numeral 100a indicates a fitting hole of the bearing 51. Both ends of the rotary shaft 54 of the driven pulley 32 are similarly supported by the bearings 53, but the bearings 53 are fixed to the adjusting plate 104 located on the back side of the side plate 100. Rotating shaft 54
Both ends of are inserted into elongated holes 100b formed in the side plate 100 and extending in the paper transport direction X. The adjusting plate 104 is
The sheet is biased in the direction opposite to the sheet transport direction X by a biasing means (not shown). That is, the adjustment plate 104 is provided so as to be movable in a direction substantially perpendicular to the rotation support shaft 15A of the transfer drum 11A. As a result, the toothed belt 33
Has a moderate tension. Reference numeral 104a
Indicates a fitting hole into which the bearing 53 is movably fitted in the paper transport direction X.

As shown in FIG. 6, when the pitch of the teeth 33a of the toothed belt 33 is P and the number of pitches is n, the pitch circumferential length (circumferential length) nP of the toothed belt 33 is
A or the outer peripheral length L of the plate drum 7A is set to be an integral multiple, and the pitch number n is set to be an integral multiple of the total tooth number z of the drive pulley 31. Specifically, it is set so that the relation of the following equation is established.

2L = nP, n = αz (α is an integer value) This relationship makes it easy to synchronize the peripheral speed of the transfer drum 11A and the conveying speed of the toothed belt 33 (moving speed of the claw member 34). The rotation cycle of the transfer drum 11A and the movement cycle of the claw member 34 can be accurately synchronized.

As described above, the sheet conveying device 5 of this embodiment
Has a unique structure as compared with that in a normal offset printing machine. In an ordinary offset printing machine, a device having a pressure cylinder for pressing the printing paper onto the transfer drum and a transfer cylinder for carrying the printing paper to the next printing unit (nip portion) is common, but in this embodiment, the toothed belt is used. The pitch circumferential length nP of 33 is set to be twice the outer circumferential length L of the plate drum 7A or the transfer drum 11A.

As shown in FIGS. 7 and 8, the claw member 34 comes into contact with one surface of the printing paper 39 or the one-side printed paper 39a on which the belt mounting portions 70, 70 forming both ends are integrally formed. It has a lower claw 60 as a possible base member and an upper claw 61 as a sandwiching member configured to be openable and closable with respect to the lower claw 60 and capable of contacting the other surface of the printing paper 39. The front end of the printing paper 39 or the one-side printed paper 39a is held between the holding portion 61a and the lower claw 60.

At both ends of the upper claw 61, a substantially tongue-shaped lever 62 as a lever-shaped member is integrally formed. Figure 7
In the above, a spindle hole 63 is formed at the upper end of the lever 62, and a hole 64 is formed at the lower end of the lever 62. On the other hand, at both ends of the lower claw 60, a support shaft hole 69 is formed.
Is formed so as to penetrate therethrough, and the above-mentioned belt attachment portions 70, 70 are integrally formed. The belt attachment portions 70, 70 at both ends of the lower claw 60 are fastened and fixed on the toothed belt 33 via screws 71. Since the structure of the claw member 34 is the same on the right front side and the left back side of FIG. 7, the right front side of FIG. 7 will be described below.

A spring 66 (torsion coil spring) for urging the upper claw 61 toward the lower claw 60 is wound around the supporting shaft hole 63 of the upper claw 61 and the supporting shaft hole 69 of the lower claw 60. After the support shaft 65 is loosely fitted, a retaining ring (not shown) is attached to restrict the movement in the axial direction, and
The support shaft 65 is fixed to a support shaft hole 69 of the lower claw 60. One end 66a of the spring 66 is bent at a substantially right angle and locked to the upper claw 61 side, and the other end 66b is bent at a substantially right angle and locked to the lower claw 61 side. As a result, the nipping portion 61 a on the free end side of the upper claw 61 is connected to the lower claw 6 via the support shaft 65.
It is swingably supported at 0 and is always closed by the urging force of the spring 66 unless an external force acts. The biasing force of the spring 66 is set such that no nipping marks are left on the printing paper 39 or the paper 39a with one-sided printing, and the posture does not shift during the transportation of the printing paper 39 or the paper 39a with one-sided printing. .

The upper claws 61 and the lower claws 60 are not limited to the shapes shown in the drawings, but may be, for example, the holding part 61 for material saving.
The shape of a may be formed in a comb shape, or a combination of a ferromagnetic material (lower claw 60) and a rubber magnet (upper claw) that attracts it by magnetic force in order to adjust the biasing force of the spring 66 may be used. Good. Further, in order to obtain the holding accuracy of the printing paper 39 in the paper transport direction X, for example, FIGS. FIG. 2 of Japanese Patent Publication No. 147358
3 to 25, or a paper clamper having a paper abutting member similar to that disclosed in FIGS. 1, 2, 22, and 26 of JP 2000-33764 A is preferable.

The shaft 67 is fitted and fixed in the hole 64 of the upper claw 61. After this, a cam follower 68 with a rollable roller is attached to the outside of the shaft 67 as a contact portion that selectively comes into contact with a cam 55A or a cam 55B described later. The cam follower 68 is, for example, a roller bearing. As a result, the cam follower 68 moves the cam 5
5A or the cam 55B can be transmitted smoothly and durable by reducing the frictional resistance and transmitting the driving force for expanding / releasing the upper claw 61 when contacting / pressing the cam 55B. If the above-mentioned advantage is not desired, the cam follower 68 may be removed, and the peripheral surface of the lower end portion of the lever 62 may be used as a contact portion that selectively contacts the cam 55A or the cam 55B.

Next, the technical contents capable of performing the opening / closing operation of the claw member 34 to a higher degree will be described. That is, in the present embodiment, the claw member 34 holds the leading end of the printing paper 39 or the paper 39a that has been single-sided printed, even when the paper is fed from the paper feeding device 4, and ejects it to the paper ejection tray 6. It is possible to release the front end of the one-side printed paper 39a as the printed paper other than when the paper is used, and the front end of the printing paper 39 or the one-side printed paper 39a by the claw member 34. One of the features is that it has a plurality of opening / closing points (for example, 5 points shown in FIGS. 9 to 12) for pinching / holding or releasing.

8 to 10, reference numeral 78A
Is a cam 5 arranged on the drive pulley 31 side, which is the paper discharge side.
Figure 5 shows a cam device with 5A. 11 and 12, reference numeral 78B indicates a cam device including a cam 55B arranged on the side of the driven pulley 32 which is the paper feeding side. As shown in FIGS. 8 to 10, the cam device 78A includes the above-mentioned cam 55A and a cam position changing means 79A for changing the position of the cam 55A for releasing and driving the pawl member 34 in accordance with two opening / closing positions described later. Have. The cam device 78B is shown in FIG.
1 and FIG. 12, the above-mentioned cam 55B,
Cam position changing means 79 for changing the position of the cam 55B that drives the pawl member 34 to be released according to three opening / closing positions to be described later.
B and.

The cams 55A and 55B have the same shape and are commonly used, but the reference numerals are changed to clarify the distinction between the paper feed side arrangement and the paper discharge side arrangement. ing. The cam device 78A and the cam device 78B have different reference numerals from the same meaning as described above, and have common components to both, so hereinafter, except for the difference, the cam device 78A side will be described as a representative. As described above, the cam device 78A and the cam device 78B have common components, which contributes to commonality of parts and cost reduction. In addition,
The rotating shaft 52 and the rotating shaft 54 have the same outer diameter, and the drive pulley 31 and the driven pulley 32 have the same number of teeth and outer diameter.

The cam 55A contacts and presses against the cam follower 68 against the biasing force of the spring 66 shown in FIG.
The large-diameter portion that releases 1 and the small-diameter portion that does not contact the cam follower 68 are integrally formed. Cam 55A shown in FIG.
Is a first part whose large diameter portion releases the upper claw 61 so as to discharge the printed printing paper 39 as the final printed matter shown by the one-dot chain line in the figure in the first paper discharge conveying direction 110 shown by the one-dot chain line. 2 shows a state in which the sheet ejection position P1 is occupied. A large-diameter portion of the cam 55A shown in FIG. 10 has a large diameter portion for ejecting the single-side printed sheet 39a indicated by the double-dot chain line in the figure in the second sheet ejection conveyance direction 111 indicated by the double-dot chain line.
1 shows a state in which the second sheet discharging position P2 for releasing 1 is occupied. A cam 55 shown by a two-dot chain line in FIG.
A indicates the cam follower 6 of the claw member 34 during double-sided printing.
8 illustrates a state in which the non-contact position PA that does not contact 8 is occupied.

The cam 55A shown in FIG. 9 which occupies the first sheet discharge position P1 as described above is the home position of the cam 55A. On the upper end surface of the cam 55A,
As shown only in FIG. 9, the light shielding piece 55b is integrally formed so as to project outward. On the other hand, a home position sensor 77A for detecting the home position of the cam 55A is fixed to the side plate 100a via an immovable member (not shown) so as to sandwich the light blocking piece 55b. The home position sensor 77A is a transmissive optical sensor including a light emitting unit and a light receiving unit.

The cam position changing means 79A is used for the cam gear 5
6, a gear train 72, a cam drive shaft 58, a stepping motor 59A as a drive source, and the like. Cam 55
In A, as shown in detail in FIG. 8, a cam gear 56 is integrally formed on an end surface portion of a cam 55A. A loose fitting hole 55a into which the rotary shaft 52 is loosely fitted is formed at the center of the cam 55A and the cam gear 56 so that the rotational driving force of the rotary shaft 52 is not transmitted to the cam 55A and the cam gear 56. There is. In FIG. 8, reference numeral 76 indicates a gear train support member that is fixed to the side plate 100 side via an immovable member (not shown). The gear train 72 is rotatably supported by a shaft 75 a that is planted in a gear train support member 76 and is a cam gear 56.
And a third gear 75 that is constantly meshed with the third gear 75 that is rotatably supported by a shaft 74 a that is planted in the gear train support member 76.
And a first gear 73 fixed to the cam drive shaft 58 and always meshed with the second gear 74.

Both ends of the cam drive shaft 58 are the side plates 1 on both sides.
00, 100 (however, the side plate 100 located in the upper part of FIG. 8)
Are rotatably supported by bearings 57, 57 mounted on the same. One end (upper side in FIG. 8) of the cam drive shaft 58 is connected to a stepping motor 59 via a worm gear (not shown), and is rotationally driven by the stepping motor 59. The gear train support member 76 includes
A loose fitting hole 76a into which the rotary shaft 52 is loosely fitted and a free fitting hole 76b into which the cam drive shaft 58 is loosely fitted are formed, and the rotational driving force of each of the rotary shaft 52 and the cam drive shaft 58 is a gear train support member. It is not transmitted to 76. A worm wheel (not shown) of the worm gears is fixed to one end of the cam drive shaft 58, and a worm (not shown) meshing with the worm wheel is fixed to the output shaft of the stepping motor 59. ing. The worm gear prevents the cam drive shaft 58 from rotating via the gear train 72 by the external force input from the cam 55A side.

As shown in FIG. 9 and FIG.
Of the cam followers 68 of the first paper discharge position P
When contacting the large diameter portion of the cam 55A which occupies the first and second sheet discharge positions P2 and is held, the upper claw 61 resists the biasing force of the spring 66 shown in FIG. By swinging, the claw member 34 is in an open state. As described above, according to the present embodiment, by providing the cam position changing means 79A, the cam 55A can be supplied from the outside of the sheet conveying device 5.
The standby position (standby phase) can be easily and accurately changed.

The cam 55B indicated by the solid line in FIG. 11 is for carrying out double-sided printing, and as shown by the broken line in the figure, the single-side printed sheet 39a is indicated by the broken line in the third sheet discharging and conveying direction 11.
3 shows a state in which the large-diameter portion occupies the third sheet discharging position P3 for releasing the upper pawl 61 so as to discharge the sheet to the third sheet discharging position P3. Further, the cam 55B shown by the two-dot chain line in FIG. 11 has a large diameter so that the single-side printed sheet 39a shown by the two-dot chain line in the figure is re-fed in the re-feeding direction 118 shown by the two-dot chain line. It shows a state in which the section occupies the second sheet sandwiching position PB2 for releasing the upper claw 61 and sandwiching the leading end of the sheet 39a with one side printed.

The description will be changed, but the cam 55 shown in FIG.
B holds the front end of the printing paper 39 by releasing the upper claw 61 to clamp the front end of the printing paper 39 fed in the paper feeding direction 109 by the first paper feeding means in the paper feeding device 4. The state occupies the first sheet nipping position PB1. FIG. 12 occupying the first sheet nipping position PB1.
The cam 55B shown in is the home position of the cam 55B. As shown only in FIG. 12, a light shielding piece 55c bent at a right angle is integrally formed on the upper end surface of the cam 55B so as to project outward. On the other hand, the light blocking piece 55c
A home position sensor 77B for detecting the home position of the cam 55B is fixed to the side plate 100a shown in FIG. 8 via an immovable member (not shown). The home position sensor 77B is a transmissive optical sensor including a light emitting unit and a light receiving unit.

The cam position changing means 79B is provided with a cam gear 56, a gear train 72, a cam drive shaft 58, a stepping motor 59B as a drive source, and the like, which are the same common parts as the cam position changing means 79A.

As described above, the sheet conveying path between the claw member 34 and the first sheet feeding means (sheet feeding roller 28 and separation pad 26) shown in FIG. A pair of rollers (not shown) are preferably arranged. Therefore, when such a pair of registration rollers is arranged, it is not necessary to change the cam 55B to the second sheet nipping position PB2 as shown by the chain double-dashed line in FIG. The sheet re-feeding guide plate 119 may be tilted slightly to the right in FIG. 11 so that the sheet 39a is re-fed toward the nip portion of the registration roller pair. In addition to this, when only double printing is required and double-sided printing is not required, the double-sided printing conveyance discharging means 112 and the cam position changing means 79B as shown in FIG. 11 and the like are removed. For example, a paper feed cam that is inserted into a support shaft (not shown) arranged in parallel with the rotary shaft 52 shown in FIG. 11 and is fixed to the support shaft so as to be non-rotatably and stably fixed as a whole. It may be.

On the upper part of the printing press main body 2 shown in FIG. 1, there is arranged an operation panel (not shown) for giving instructions to each of the above-mentioned devices of the offset printing press 1 for operation. On the operation panel, the single-side printed sheet 39a is fed with a sheet re-feeding device 40.
A double-printing print mode setting key (not shown) for setting a double-printing print mode for performing double-printing by re-feeding paper, and a double-sided print mode for performing double-sided printing. A double-sided print mode setting key (not shown) as a double-sided print mode setting unit for setting, a ten-key pad (not shown) for setting the number of print sheets 39 to be printed, and a color designation key for selectively setting a color to be printed Etc. are provided.

Further, at an appropriate portion of the printing press main body 2 shown in FIG. 1, a control device (not shown) as a control means for controlling the operation of the above-mentioned respective devices of the offset printing press 1 is arranged. The control device includes, for example, a CPU (central processing unit), an I / O (input / output) port (not shown), a ROM (read-only storage device), a RAM (readable / writable storage device), a timer (not shown), and the like.
It is provided with a microcomputer having a configuration in which they are connected by a signal bus (not shown). The color designation key, the double-printing print mode setting key, the double-sided printing mode setting key, home position sensors 77A, 7
7B is electrically connected to the CPU through the input port and the like, and the stepping motors 59A and 59B are electrically connected to the CPU through a motor drive circuit (not shown) and the output port. The CPU, based on signals from the double-press printing mode setting key or the double-sided printing mode setting key and the home position sensor 77A and / or the home position sensor 77B, the stepping motor 59A and / or the cam position varying means 79A and / or the stepping motor 59A. It has a function of controlling the stepping motor 59B of the cam position changing means 79B.

Next, the operation around the plurality of developing devices 10A to 10D, the sheet conveying device 5 and the re-feeding device 40 will be described in detail, focusing on the points different from the outline of the printing operation described above. The following operations are all automatically performed under the command from the control device except for the operation of various keys by the operator and the operation of supplying the printing paper 39.

First, a supplementary description will be given of the above-mentioned normal single-sided printing operation. In this normal single-sided printing operation, the operator does not press the double-printing print mode setting key or the double-sided printing mode setting key on the operation panel. The operator selects and sets the print image color to be printed by the color designation key of the operation panel, and sets the number of prints to be printed by the ten key. Here, for example, it is assumed that two colors, cyan and magenta, are selected and set by the color designation key. Next, when the start switch is pressed, a series of steps from the original reading step / plate making step to the cleaning step similar to the above is continuously and automatically performed.

Since the double-press printing mode setting key and the double-sided printing mode setting key are not pressed, the control device recognizes that the normal single-sided printing operation is performed,
Based on the home position detection signals from the home position sensors 77A and 77B, the cam 55B of the cam position changing means 79B shown in FIG. 12 occupies the first sheet nipping position PB1 shown in FIG. 12, and FIG. The cam 55A of the cam position changing means 79A shown in FIG.
It is determined that the sheet ejecting position P1 is occupied. More specifically, since the CPU has not transmitted the double-printing print mode signal from the double-printing print mode setting key and the double-sided printing mode signal from the double-sided print mode setting key, the cam shown in FIG. 55B is shown in FIG.
1st paper holding position PB1 (home position) shown in
Control the stepping motors 59A and 59B so that the cam 55A shown in FIG. 9 occupies the first sheet discharge position P1 (home position) and holds this position. More specifically, the cam 55
B to the stepping motor 59B so as to hold the first sheet nipping position PB1, and to the stepping motor 59A so that the cam 55A holds the first sheet ejecting position P1.
An exciting current is supplied to each stepping motor 59A,
The rotation position of 59B is held).

Similar to the paper feeding operation from the paper feeding device 4 in the above-described normal single-sided printing operation, the leading end of the printing paper 39 is clawed by the rotation start of the paper feeding roller 28 while the timing with the ink image is set. The sheet is fed at a timing synchronized with the opening operation of the member 34. At the same time, the cam follower 68 of the claw member 34 holds the cam 55 held at the first sheet nipping position PB1 as shown in FIG.
A state in which the upper claw 61 is opened from the lower claw 60 by abutting on the large diameter part of B and swinging the upper claw 61 against the biasing force of the spring 66 shown in FIG. Then, the upper claw 61 is expanded, and then the upper claw 61 is closed at a predetermined timing, so that the front end portion of the printing paper 39 is clamped by the claw member 34. When the printing paper 39 is sandwiched by the claw members 34, the printing paper 39 is further conveyed to the downstream side in the paper conveyance direction X by the rotation of the toothed belt 33.

When the registration operation by the pair of registration rollers is involved, the process is as follows. That is, first, as described above, the printing paper 39 on the paper feed tray 27 is set to 1 by the cooperative action of the paper feed roller 28 and the separation pad 26.
They are separated and fed one by one. Printed paper 3 fed
9 is temporarily stopped by the pair of registration rollers 30, and the oblique displacement or the like is corrected by a method such as excessive feeding. Then, the electric motor of the sheet conveying device 5 is driven so that the toothed belt 33 rotates at a predetermined linear velocity, so that the printing paper 39 causes the registration roller pair 30 to be synchronized with the opening operation of the claw member 34. The following operations are the same as those described above in the supplementary explanation.

Although a part of the description will be mixed up, two colors of cyan and magenta are selectively set by the color designation key after the original reading process and the plate making process similar to those in the above-described normal single-sided printing operation are completed. , Contacting / separating means 9 at a predetermined timing
7A and the contacting / separating means 97C are controlled to drive the ink inking rollers 83A and 85A of the developing device 10A to move to the plate drum 7.
In A, ink inking rollers 83C, 85 of the developing device 10C
C is pressed against the plate drum 7B. At this time, the developing device 10B and the developing device 10D are still in the retracted position. The cyan ink adheres to the hydrophilic portion of the image data portion of the plate 8A for plate making, and the magenta ink adheres to the hydrophilic portion of the image data portion of the plate 8B for plate making, respectively. .

At the printing stations 3A and 3B, when the developing process is completed as in the normal single-sided printing operation,
An intermediate transfer process similar to that described above is performed, and the plate drum 7
The cyan and magenta inks adhered to the printing plates 8A and 8B on A and 7B according to the image data are transferred onto the transfer drum 11.
The cyan and magenta ink images are formed on the transfer blankets by being transferred to the transfer blankets on A and 11B.

While the cyan and magenta ink images are formed on the transfer drums 11A and 11B, the leading edge of the printing paper 39 is printed again by the toothed belt 33 while timing with the ink images is set as described above. It is conveyed to the sections 13A and 13B. Each printing unit 13A, 1
In 3B, the same final paper transfer process as described above is performed to perform two-color overprinting, and a desired two-color printed image is obtained. In this final paper transfer step, the printing paper 39 is naturally transported at the same speed as the peripheral speed of the transfer drums 11A and 11B, that is, at the same transport speed of the toothed belt 33 as the peripheral speed of the transfer drums 11A and 11B. It

Printing paper 39 on which a two-color printing image is formed
Are further transported by the toothed belt 33 toward the downstream side in the sheet transport direction X. When the claw member 34 holding the leading end of the printing paper 39 is conveyed to the vicinity of the press roller 37a, as shown in FIG. 9, the cam follower 68 of the upper claw 61 is provided.
Is held at the first paper discharge position P1 by the cam 55A
The upper pawl 61 swings against the urging force of the spring 66 shown in FIG. Become. By the releasing operation of the claw member 34 at this position, the front end of the printing paper 39 on which the two-color printing image is formed is released and ejected in the first paper ejection conveyance direction 110, and the paper ejection roller pair 36 shown in FIG. Thus, the sheet is guided and conveyed toward the sheet discharge tray 6, and is stacked while being aligned by the side guide pair 38.

When the printing of the number of prints set by the ten keys is completed, the contacting / separating means 97A, 97B are driven to cause the developing devices 10A, 10C to move to the plate drums 7A, 7C.
Separated from B, they occupy their initial positions. At the same time, the plate-drum 7 is activated by the operation of the contact / separation displacement means.
A and 7B are separated from the transfer drums 11A and 11B and occupy their initial positions. When these separating operations are performed, the same cleaning process as in the above-described normal single-sided printing operation is performed, and at the same time, the winding shaft 17A shown in FIG. Further, the same operation as described above is performed on the plate drum 7B side, so that the plate drums 7A and 7B
On B, new printing plates 8A, 8B for the next plate making are unwound and wound.

Next, the double printing operation will be described. First, the operator presses the double-printing print mode setting key, and selects and sets the print image color (first or second color) to be printed for the first time by the color designation key. Here, it is assumed that, for example, two colors of cyan and magenta are selectively set by the color designation key as described above. Next, after setting the number of prints to be printed with the ten keys, the print image color (third and fourth colors) desired to be printed a second time is selected and set with the color designating key. Here, for example, two colors of yellow and black are selected and set by the color designation key. Next, when the start switch is pressed, a series of processes from the document reading process / plate making process to the cleaning process are continuously and automatically performed as in the above.

By performing the above key operation and the like, the control device recognizes that the double-printing operation is performed, and based on the home position detection signal from the home position sensor 77B, the cam 55B shown in FIG. Occupies the first sheet holding position PB1 shown in FIG. At the same time, stepping is performed to change the position and phase of the cam 55A from the state in which the cam 55A occupies the first sheet ejection position P1 shown in FIG. 9 to the state in which it occupies the second sheet ejection position P2 shown in FIG. A predetermined drive pulse is supplied to the motor 59A. Specifically, in FIG. 9, when the stepping motor 59A is driven forward (or reversely) by a predetermined number of steps, for example, the cam drive shaft 58 rotates clockwise, so that the gear train 72 and the cam gear 56 are rotated. The rotational driving force is transmitted to the cam 55A via the cam 55A, and the cam 55A rotates counterclockwise by a predetermined angle corresponding to a predetermined number of steps of the stepping motor 59A, as shown in FIG. The stepping motor 59A is held while occupying the second sheet discharging position P2 shown in FIG. 10 (more specifically, the stepping motor 59A is supplied with an exciting current so that the cam 55A holds the second sheet discharging position P2. Hold the rotation position of. A detection unit having the same configuration as the home position sensor 77A for detecting the state where the cam 55A occupies the second sheet discharge position P2 shown in FIG. 10 may be added.

Next, after the same document reading step, plate making step, and final sheet transfer step as in the above-described normal single-sided printing operation, single-sided printing in which two-color printed images of cyan and magenta are formed in FIG. The cam follower 68 of the upper pawl 61 is held at the second paper ejection position P2 when the pawl member 34 holding the front end of the completed paper 39a is conveyed to a position slightly past the pressing roller 37b. 5
By contacting the large diameter portion of 5A, the upper claw 61 is opened from the lower claw 60 through the same operation as described above. By the releasing operation of the claw member 34 at this position, the front end of the paper 39a with one side printed is released and guided by the guide plate 41 to be ejected in the second paper ejection conveyance direction 111, and further conveyed by the feed roller pair 42. The sheet is discharged while being guided along the pair of guide plates 43 shown in FIG. 4, and is stacked on the bottom plate 45 of the refeed tray 44. At this time, a kind of reversing conveyance path is formed by the toothed belt 33, the pressing roller 37b, the guide plate 41, the feed roller pair 42, and the guide plate pair 43 located on the lower side of FIG. The printed image 39a is stacked on the bottom plate 45 with its printed image surface being the lower surface (back surface) side.

2 for the number of prints set by the ten keys
Bottom plate 45 of paper 39a that has been color printed and has been printed on one side
When the stacking on the top is completed, the control device immediately recognizes that the refeed operation or the final paper discharge operation is performed, and the cam 55B shown in FIG. 12 causes the cam 55B shown in FIG. From the state of occupying PB1 (which is also the home position), the second sheet nipping position PB2 shown in FIG.
A predetermined drive pulse is supplied to the stepping motor 59B so as to change the position and phase of the cam 55B so as to occupy the position. Specifically, in FIG. 12, when the stepping motor 59B is driven in the normal direction (or reverse direction) by a predetermined number of steps, for example, the cam drive shaft 58 is rotated in the counterclockwise direction, so that the gear train 72 and the cam gears are rotated. 5
The rotational driving force is transmitted to the cam 55B via 6 and the cam 55B moves to the stepping motor 5 as shown in FIG.
By rotating in the clockwise direction by a predetermined angle corresponding to the predetermined number of steps of 9B, the second paper holding position PB2 shown in FIG. 11 is held and held (more specifically, the cam 55B is An exciting current is passed through the stepping motor 59B so as to hold the second sheet nipping position PB2 to hold the rotational position of the stepping motor 59B). In addition,
You may add the detection means of the same structure as the said home position sensor 77B for detecting the state where the cam 55B occupied the 2nd paper holding position PB2 shown in FIG.

At the same time, from the state in which the cam 55A shown in FIG. 10 occupies the second sheet discharge position P2 shown in FIG. 10, the first sheet discharge position P1 (home position) shown in FIG.
After a predetermined drive pulse is supplied to the stepping motor 59A so as to change the position and phase of the cam 55A so that the cam 55A occupies the position, the magnet is excited. As a result, the cam 55A is held at the first sheet ejection position P1 shown in FIG.

On the other hand, when the above two-color printing is completed,
In each of the printing stations 3A and 3B, the same cleaning process as in the normal single-sided printing operation is performed, and at the same time, in the plate drums 7A and 7B, as in the normal single-sided printing operation, a new printing process for the next plate making is performed. The plates 8A and 8B are unwound and wound, and the second sheet (third and fourth colors) in each of the writing devices 9A and 9B based on the image data of the second sheet.
Image data is written on the printing plates 8A and 8B.

When it is confirmed by the control device that the cam 55B is held at the second sheet holding position PB2 shown in FIG. 11, the toothed belt 33 is rotated at a predetermined linear velocity by a command from the control device. As described above, the electric motor of the sheet conveying device 5 is driven, and in response to this, the single-side printed sheets 39a of the bottom plate 45 are separated one by one by the cooperative action of the sheet feeding roller 46 and the separating pad 47a, and re-formed. While being fed and further guided along the re-feeding guide plate 119, the sheet 39 a with one side printed is fed by the feeding roller 46 at a timing synchronized with the opening operation of the claw member 34. At the same timing, the cam follower 68 of the claw member 34 comes into contact with the large diameter portion of the cam 55B held at the second sheet nipping position PB2 as shown in FIG. 11, thereby performing the same operation as above. After that, the upper claw 61 is opened from the lower claw 60 and the upper claw 61 is expanded,
Next, the top claw 61 is closed at a predetermined timing so that the leading end of the single-side printed sheet 39a that has been re-fed is claw member 3
It is sandwiched by 4. When the registration operation is performed by the registration roller pair, the rotational movement of the cam 55B to the second sheet holding position PB2 is unnecessary.

The single-side printed sheet 39a sandwiched by the claw members 34 has a sheet feeding roller 46, a sheet re-feeding guide plate 119,
Since it is re-fed through the toothed belt 33 on the driven pulley 32, which is a kind of reversing conveyance path, the printed image surface side faces upward, and the unprinted image surface side faces the outer surface of the toothed belt 33. The contacting side is conveyed in the sheet conveying direction X in FIG. 1 by the rotation of the toothed belt 33.

Although a part of the description will be mixed up, after the plate making process corresponding to the image data of the second sheet is completed, the color designation key is used to change the number of yellow and black in the second printing.
Since the color is selected and set, the contacting / separating means 97B and the contacting / separating means 97D are driven at a predetermined timing to press the developing device 10B against the plate drum 7A and the developing device 10D against the plate drum 7B. At this time, the developing device 10A
And the developing device 10C remains in the retracted position.
Yellow ink is added to the hydrophilic portion of the image data portion of the plate 8A for printing, and the plate 8B for printing is also prepared.
The black ink will be attached to the hydrophilic portions of the image data portion.

When the developing process is completed in the printing stations 3A and 3B, an intermediate transfer process similar to that described above is carried out, and the printing plates 8A and 7A on the plate drums 7A and 7B are processed.
The yellow and black inks attached to 8B according to the image data are transferred to the transfer blanket on the transfer drums 11A and 11B, and yellow and black ink images are formed on the transfer blanket.

While the yellow and black ink images are formed on the transfer drums 11A and 11B, while the timing with the ink images is set as described above, 2
The leading end of the one-side printed sheet 39a on which the color print image is formed is again printed by the toothed belt 33 with the printing units 13A and 13A.
It is transported to B. The same final paper transfer process as described above is performed in each of the printing units 13A and 13B to perform 4-color overprinting, and a desired 4-color printed image is obtained. Hereinafter, the same operation as the paper discharge operation during the normal single-sided printing operation is performed. If there is only one printing station 3A and one plate drum 7A, it is possible to perform not only the above-described four-color overprinting but also two-color overprinting.

Next, the double-sided printing operation will be described. First, the operator presses the double-sided printing mode setting key,
The print image color (first or second color) desired to be printed on the front surface of the printing paper 39 is selected and set by the color designation key. here,
Similarly to the above, it is assumed that, for example, two colors of cyan and magenta are selectively set by the color designation key. Next, after setting the number of prints to be printed by the ten keys, the print image color (third and fourth colors) desired to be printed on the back surface of the printing paper 39 is selectively set by the color designation key. Here, for example, two colors of yellow and black are selected and set by the color designation key. Then, when the start switch is pressed, the document reading process and
A series of processes from the plate making process to the cleaning process are continuously and automatically performed.

By performing the above key operation and the like, the control device recognizes that the double-sided printing operation is performed, and first,
Based on the home position detection signal from the home position sensor 77B, the cam 55B shown in FIG.
It is determined that it occupies the first sheet nipping position PB1 shown in FIG. At the same time, the stepping motor 59A changes the position and phase of the cam 55A from the state where the cam 55A occupies the first sheet discharge position P1 shown in FIG. 9 to the state where it occupies the non-contact position PA shown in FIG. After a predetermined drive pulse is supplied to, it is excited. As a result, the cam 55A is held at the non-contact position PA.

Hereinafter, until the first and second color (cyan, magenta) print images are formed on the surface of the printing paper 39, the same operation as in the above-described double-printing printing operation is performed except for the points described below. That is, as compared with the operation of the sheet conveying device 5 in the double-press printing operation, after feeding the first printing sheet 39, as shown in FIG. 12, the first sheet nipping position PB1.
The cam 55B that occupies the position of the third sheet discharge position P3 shown in FIG. As a result, the cam 55B is held at the third sheet ejection position P3 shown in FIG. Two
The cam 55 is fed after the first printing paper 39 is fed or before and after the set number of prints are fed.
B is the first sheet nipping position PB1 and the third sheet ejection position P
It is held by being rotationally displaced with respect to 3.

As shown in FIG. 10, the claw member 34 holding the front end of the one-side printed sheet 39a on which the two-color printed image is formed is held by the toothed belt 33 to the pressing roller 37.
Since the cam 55A is held at the non-contact position PA when it is conveyed to a position slightly past b, the upper pawl 61
11, the upper follower 61 remains in the closed state without releasing, and therefore the double-sided printing conveyance discharge path 117 shown in FIG.
Is transported to the vicinity of.

When the claw member 34 is conveyed by the toothed belt 33 to the vicinity of the double-sided printing conveyance discharge path 117, the cam follower 68 of the upper claw 61 is held at the third sheet discharge position P3 shown in FIG. By contacting the large diameter portion of the cam 55B, the upper claw 61 is opened from the lower claw 60 through the same operation as described above. Claw member 34 at this position
By the releasing operation of 1., the front end of the sheet 39a with one-sided printing is released and is guided in the guide plate 114 to be ejected in the third sheet ejecting and conveying direction 113, and further the feed roller pair 1
Guide plate pair 1 conveyed by 15 and shown in FIGS. 4 and 11.
16 is ejected while being guided along with the refeed tray 44.
It will be loaded on the bottom plate 45 of the. At this time,
1. The toothed belt 33 and the guide plate 11 located on the lower side of 1.
4, a kind of reverse conveyance path is formed by the pair of feed rollers 115 and the pair of guide plates 116, so that the single-side printed sheet 39a is stacked on the bottom plate 45 with its printed image side facing upward (front side).

2 for the number of prints set by the ten keys
Bottom plate 45 of paper 39a that has been color printed and has been printed on one side
Upon completion of stacking on the top, the control device immediately recognizes that the re-feeding operation or the final discharging operation is performed, and the cam 55B shown in FIG. 11 causes the cam 55B shown in FIG.
Is supplied to the stepping motor 59B so as to change the position and phase of the cam 55B from the state in which the second sheet holding position PB2 shown in FIG. As a result, the cam 55B is held at the second sheet nipping position PB2. At the same time, FIG.
9A, the stepping motor 59A changes the position and phase of the cam 55A from the state where it occupies the non-contact position PA to the state where it occupies the first sheet ejection position P1 (home position) shown in FIG. After a predetermined drive pulse is supplied to, it is excited. As a result, the cam 55A is held at the first sheet ejection position P1 shown in FIG.

On the other hand, the printing paper 39 is printed on the surface 2
When the color printing is completed, except for the following points, the above 2
The same operation as the reprint printing operation is performed. That is, in the double-sided printing operation, the single-side printed sheet 39 a held by the claw member 34 is printed on the sheet feeding roller 46 and the sheet re-feeding guide plate 11.
9. Since it is re-fed through a kind of reversing conveyance path of the toothed belt 33 on the driven pulley 32, the printed image side thereof faces downward, and the unprinted image side (back side).
The side does not contact the outer surface of the toothed belt 33, and the toothed belt 33 is conveyed in the sheet conveying direction X in FIG. 1 by the rotation of the toothed belt 33. 4th color yellow and black 2
Color overprinting is performed, and a desired double-sided printed image with two colors on each side is obtained. Hereinafter, the same operation as the paper discharge operation during the normal single-sided printing operation is performed.

In order to obtain highly accurate print image quality in the second printing such as double printing and double-sided printing, not only the high precision reproducibility in the plate making operation as described above,
A technology that can improve the sheet transportability at the time of re-feeding is also essential. Generally, when a printed matter that has been printed once is set in the paper feeding device again, it is difficult to convey the paper with high accuracy due to unevenness of the paper, dry-dry fixing and the like. In the present embodiment, a description of a specific example of such improvement in sheet feeding accuracy is omitted this time. For example, a method of adjusting the position of a sheet feeding table or a bottom plate on which a sheet feeding device or a sheet refeeding device is stacked, For example, the printing paper is applied to the abutting plate and the position of each printing paper is regulated and adjusted.
In terms of equipment, it can be realized by techniques that have been put to practical use or improved techniques.

As described above, according to this embodiment, all the above-mentioned conventional problems can be solved. in addition,
Four color developing devices 10A to 10D, a paper transport device 5,
By cooperating and interlocking with the re-feeding device 40, a novel printing device such as double printing, full color printing or double-sided printing, which has never been realized, is provided. With conventional two-color machines, it is very troublesome to print with more ink, and most of the printed materials are returned to the paper feeder, and moreover, printing is not possible for overprinting with the second printing. Since the images must be accurately overlapped, the paper feeding device not only controls the position of the printing paper in the flow direction (vertical direction) but also adjusts the position of the printing paper in the width direction (horizontal direction). In addition, remove the printed ink from the developing device, clean it and replace it with another ink, and write the image data for the second time on the plate making device separately, develop the image data, and install it on the printing machine. It was the actual situation that the second printing was performed with the following operation and time and effort.

However, in the present embodiment, in order to save the troublesome operations described above, a plurality of (four color) developing devices 10A to 10D are shared by the plate drums 7A and 7B, and tandem paper feeding is possible. The continuous paper feeding is possible by having the simple paper feeding device 4, the replenishment operation of the printing paper 39 can be performed without interrupting the operation of the offset printing machine 1, and the single-side printed paper 39a can be fed again. Sheet feeding device 4 and sheet re-feeding device 40 for ensuring conveyance accuracy
And a plate drum 7A which is easy to replace the writing devices 9A, 9B and the printing plates 8A, 8B capable of direct plate making,
It is equipped with 7B. With such an apparatus configuration, there is an advantage that printing of another color can be performed very easily, and four-color printing of full color can be performed easily because it is a two-color machine as an embodiment.

Further, the paper conveying device 5 holds at least one claw member 34 for holding the leading end of the printing paper 39 fed from the paper feeding device 4, and fixing the claw member 34 to the printing portions 13A, 13B. A cam device 78A provided with a toothed belt 33 stretched between the pulleys 31 and 32 and driven to rotate so as to travel from the upstream side to the downstream side, and cams 55A and 55B that drive the claw members 34. , 78B, it is possible to carry out highly accurate sheet transportation without variations in resist, highly accurate alignment transportation without color misregistration necessary for image formation, and claw members. It is possible to use a method for utilizing the holding and releasing of the leading end portion of the printing paper 39 by 34 in a complicated and multifunctional manner. Also,
A pair of toothed belts 33 are provided at intervals in the rotation axis direction of the transfer drums 11A and 11B, and a pair of pulleys 31 and 32 are also provided.
Are stretched so as to be substantially perpendicular to the rotation axes of the transfer drums 11A and 11B, and the traveling directions thereof are substantially parallel to each other.
Since it is configured so as to be bridged and fixed between the toothed belts 33 so as to be substantially parallel to the rotation axis of B, the printing paper 39 is conveyed at a right angle to the rotation axes of the transfer drums 11A and 11B. Therefore, it is possible to prevent the skew of the printing paper 39 and the paper 39a that has been printed on one side when the paper is conveyed.
Further, the width between the pair of toothed belts 33 is X in the paper conveyance direction.
Since the claw member 34 having a width larger than the width of the printing paper 39 can be fixed because the configuration is larger than the maximum width of the printing paper 39 that is orthogonal to Can be prevented from changing.

Also, the pitch circumference of the toothed belt 33 is
The length is an integral multiple of the outer peripheral length of the transfer drum 11A, 11B or the plate drum 7A, 7B, and the toothed belt 33
Since the number of teeth or the number of pitches is an integral multiple of the total number of teeth of the toothed pulleys 31 and 32, there is almost no slip between the normal toothed belt having no tooth and each pulley, The rotation cycle of the transfer drums 11A and 11B and the movement cycle of the claw member 34 fixed on the toothed belt 33 can be easily and accurately synchronized, and more accurate resist transfer can be performed, and at the same time, image transfer can be performed. Positional deviation and color deviation can be prevented with high accuracy and reliability. Further, by providing the cam position changing means 79A, 79B, the standby position of the cams 55A, 55B can be easily and accurately changed from the outside of the sheet conveying device 5 to open / close the claw member 34 on the toothed belt 33. The position can be freely changed, and advanced paper transportation and advanced print image formation can be performed in cooperation with a peripheral device (paper refeed device 40 in the above example) of the paper transportation device 5. . Since a method for utilizing the opening / closing operation of the claw member 34 in a complicated and multifunctional manner is possible, the related functions such as double printing and double-sided printing can be easily realized as described above.

Although the toothed belt 33 is used in the present embodiment, the toothed belt 33 is not limited to the toothed belt 33 as long as the advantage (slip is very small) is not so desired, and a normal flat belt or the like is used. A belt may be used. The printing plate is not limited to the structure incorporated in the plate drum 7A or the like as shown in FIG. 2 as long as the above advantages are not desired, and for example, another writing device (plate making) outside the printing device is used. The plate produced by the apparatus) may be attached or inserted to the plate drum 7A or the like and wound around the plate drum 7A or the like.

In this embodiment, two printing stations 3
A, 3B, and the printing station 3A is the developing device 10
By the A and 10B, the printing station 3B becomes the developing device 1
0C and 10D have been described as an example in which inks of different colors are supplied, but the present invention is not limited to this, and some of them are the same for the purpose of reducing the number of times of ink replenishment of an ink replenishment magazine. (See claim 7).

The offset printing machine 1 described above is an example of a two-color machine, but it also provides a very effective system for a one-color machine or a four-color machine. In this way, the high-precision writing devices 9A and 9B, the high-precision paper transport device 5, the re-feeding device 40, and the like, as well as the plurality of developing devices 10A to 10A.
By providing 10D, the offset printing machine 1 of the present embodiment can obtain full-color printing, that is, a printed material having a doubled number of colors by simple operation and control, much more easily than the conventional two-color printing machine. In the offset printing machine 1 of the present embodiment, the two-color machine has been described as an example of the arrangement of two developing devices on one plate drum, but it goes without saying that a plurality of such devices may be provided, for example, three.
It goes without saying that increasing the number to four or four is naturally included in the form example of the printing apparatus. Further, if the plate drum is a double cylinder and the paper transporting device is a belt having a triple length, it is possible to perform printing in full color at high speed by using two plate drums without the need to replace the printing plate. in this case,
The re-feeding device is only for back side printing, that is, double-sided printing,
At the time of full-color printing, the printing paper may be rotated twice around the printing unit by a triple belt and printing may be performed, and then discharged.

The color of the ink used is not limited to the above embodiment, and any color may be used, and the combination of which color ink is used at which printing station is arbitrary. The printing station is a printing drum or a printing drum that supplies the ink to the master on the printing drum by winding the printing master on the printing drum without the transfer drum. It may be a stencil printing apparatus formed by a pressing means (press roller, impression cylinder, or intermediate pressing roller type plate cylinder) that presses the sheet.
In this case, the ink supply device as a developing device is provided inside the printing drum, or, for example, JP-A-7-17.
No. 013 discloses a structure in which ink is supplied from the outside of a printing drum, that is, a structure in which ink is supplied to a master on which a plate has been made and a printing image is formed on printing paper. It can also be applied to a printing device (see claim 1).

The writing on the printing plate is not limited to the laser plate making apparatus, but may be performed by a well-known plate making apparatus or writing means such as one using a thermal head and a platen roller, one developing a latent image with toner, and the like. Good. The printing plate is not built in the plate drum, and may have a known configuration in which it is supplied onto the plate drum from the outside.In this case as well, writing is performed by a laser beam, a thermal head, or a latent mark. It may be any of those developed by developing an image with toner.

In the above embodiment, the case where a plurality of (two) plate drums are provided has been described. However, even if there is only one plate drum, the chain delivery system using a belt or a toothed belt provides a pressure drum system. It is advantageous in comparison. That is, in the case of the chain delivery system, the overall height or width of the printing apparatus can be reduced or narrowed, so that the printing apparatus can be downsized. In addition, there is an advantage that the degree of freedom in design is increased in the transportation of the printing paper after printing. This is because, for example, when it is desired to provide an ink drying step, it is sufficient to increase the length of the belt or the toothed belt.

Further, since the printing paper can be separated by the curvature in the pulley portion around which the belt or the toothed belt is wound, the printing paper can be easily delivered to the next process. This is because there is much free space in the pulley section. These advantages are similarly obtained in the configuration having a plurality of plate drums. As described above, the present invention has been described with reference to specific embodiments including examples, but the configuration of the present invention is not limited to the above-described embodiments and the like, and may be configured by appropriately combining these. However, it is obvious to those skilled in the art that various embodiments and modifications can be configured within the scope of the present invention depending on the necessity and application thereof.

[0141]

As described above, according to the present invention,
A novel printing apparatus can be provided by solving the problems of the conventional apparatus as described above. The effects of each claim are as follows.

According to the first to sixth aspects of the present invention, the above-described configurations can realize double printing and double-sided printing with a simple apparatus configuration.

According to the seventh aspect of the present invention, the developing device is configured to contain ink that is partially the same or different in color depending on the application.
In addition to the effects of the invention described above, two-color printing, full-color printing, etc. can be realized with a simple device configuration.

[Brief description of drawings]

FIG. 1 is a schematic front view of an offset printing machine as a printing apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an internal structure of a plate drum that winds and holds a printing plate.

FIG. 3 is a cross-sectional view around a developing device.

FIG. 4 is a cross-sectional view around the re-feeding device.

FIG. 5 is a schematic perspective view of a main part of the sheet conveying device.

FIG. 6 is a partially enlarged perspective view of a toothed belt.

FIG. 7 is an exploded perspective view showing a configuration of a claw member.

FIG. 8 is a partial cross-sectional plan view of the periphery of a cam device including a cam position changing unit in the paper transport device.

FIG. 9 is a partial cross-sectional front view showing a releasing operation of the claw member in a state where the cam in the sheet conveying device occupies the first sheet unloading position by the cam position changing means.

FIG. 10 is a partial cross-sectional front view showing the releasing operation of the claw member and the like in the state where the cam in the sheet conveying device occupies the second sheet unloading position by the cam position changing means.

FIG. 11 is a partial cross-sectional front view showing the releasing operation of the claw member in a state where the cam in the sheet transporting device occupies the second sheet sandwiching position and the third sheet unloading position by the cam position varying means.

FIG. 12 is a partial cross-sectional front view showing the releasing operation of the claw member in a state where the cam in the sheet conveying device occupies the first sheet nipping position by the cam position changing means.

[Explanation of symbols]

1 Offset printing machine as printing device 3A, 3B printing station 4 First paper feeder 5 Paper transport device 7A, 7B version drum 8A, 8B printing plate 10A, 10B, 10C, 10D developing device 11A, 11B transfer drum 13A, 13B Printing department 29A, 29B Transfer roller as transfer member 31 Drive pulley as a toothed pulley 32 Driven pulley as toothed pulley 33 toothed belt 34 Claw member as holding means 39 printing paper 39a Single-side printed paper 40 Refeeding Device as Second Paper Feeding Device 44 Refeed tray as storage means 49 Transporting and discharging means for double printing 55A, 55B Cam as driving means 60 Lower claw as a base member constituting holding means 61 Upper claw as a holding member that constitutes a holding means 62 Lever as lever-shaped member 68 Cam follower with roller 78A, 78B cam device 79A, 79B cam position changing means 112 Transporting and discharging means for double-sided printing P1 First paper ejection position P2 Second paper ejection position P3 Third paper ejection position PA non-contact position PB1 First paper holding position PB2 Second paper holding position X Paper transport direction Width between W belts

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Claims (7)

[Claims] 1. At least one plate drum for holding a printing plate, a developing device for supplying ink to the printing plate on the plate drum, and a sheet for conveying a printing sheet toward a printing section of the plate drum. A printing apparatus having a carrying device and a first paper feeding device for feeding printing paper to the paper carrying device, comprising a storage unit for temporarily storing the printed paper from the paper carrying device, A printing apparatus comprising a second paper feeding device that feeds printed paper from the storage means toward the printing unit again. 2. A printing plate provided at least one plate drum for holding the printing plate, a developing device for supplying ink to the printing plate on the plate drum, and facing the plate drum so as to be in contact therewith. A transfer drum to which the ink image formed on the transfer drum is transferred, a paper transport device that transports the print paper to the transfer drum, a first paper feeder that feeds the print paper to the paper transport device, and the transfer drum In a printing device having a transfer member for pressing a sheet to form a printing unit and pressing the printing sheet conveyed by the sheet conveying device against the transfer drum, the printed sheet from the sheet conveying device is temporarily removed. A printing apparatus, comprising: a storage unit configured to temporarily store the printed sheet, and a second sheet feeding device configured to feed the printed sheet from the storage unit to the printing unit again. 3. The printing device according to claim 1, wherein the paper transporting device holds the leading end of the printing paper other than when the paper is being fed, and the leading end of the printed paper when the paper is not being ejected. Holding means capable of releasing the section, and a belt which is stretched between the pulleys and is rotationally driven so as to fix the holding means and run the printing section from the upstream side to the downstream side thereof. A driving means for driving the holding means, and a plurality of opening / closing portions for holding or releasing the leading end portion of the printing paper by the holding means, provided between the paper conveying device and the storage means, Two
A printing apparatus comprising: a double-printing transport and discharge unit for performing a double-press print and / or a double-sided print transport and discharge unit for performing a double-sided print. 4. The printing apparatus according to claim 3, wherein the drive means includes a cam device having a cam, and a cam position for changing the position of the cam for driving the holding means in accordance with each of the opening / closing positions. A printing apparatus comprising variable means. 5. The printing apparatus according to claim 1, further comprising a plurality of the developing devices for each of the plate drums, and a feeding operation of a printed sheet by a second paper feeding device. A printing apparatus capable of performing double printing and / or full-color printing and / or double-sided printing in conjunction with. 6. The printing apparatus according to claim 5, wherein printed paper is fed between the printing unit and the second paper feeding device by cooperation of the paper feeding device and the second paper feeding device. A printing apparatus which is conveyed and printed a plurality of times, and is controlled such that the plurality of times of printing are performed not only during single-sided printing but also during double-sided printing. 7. The printing device according to claim 5, wherein the developing device contains inks that are partially the same or different in color depending on the application.