JP2009143138A - Double-sided printer and stencil printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in stencil printing wherein printing can be performed quickly at low cost, while variable data such as page printing and address printing cannot be handled due to the use of a plate, and in consequence, a variable portion is printed again by a color printer of ink-jet or the like after stencil-printing the same portion, causing time-consuming. <P>SOLUTION: A paper re-feeding part 3 is used for temporarily holding surface printed paper PA formed with a print image on the surface corresponding to a first plate-making image A or a second plate-making image B in a first printing part 20 and then reversing and re-feeding the paper toward the first printing part 20. A second printing part 5 (an ink-jet printing part 30 or the like) for printing in a different printing method from the first printing part 20 is arranged between the first printing part 20 (a stencil printing part) and a paper feeding part 60. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a double-sided printing apparatus and a stencil printing apparatus, and more specifically, a first printing unit capable of printing on both sides of a sheet-like recording medium (hereinafter also simply referred to as “sheet”) in one step; The present invention relates to a new composite type (hybrid type) duplex printing apparatus and stencil printing apparatus in which a second printing unit that performs printing by a printing method different from that of a first printing unit is arranged between a sheet feeding unit and a sheet feeding unit.

In general, a laminate structure in which a thermoplastic resin film having a thickness of approximately 1 to 2 μm and a porous support made of Japanese paper fiber or synthetic fiber or a mixture of Japanese paper fiber and synthetic fiber are bonded together. The surface of the thermoplastic resin film of the stencil master (hereinafter simply referred to as “master”) is brought into contact with a number of heating elements of the thermal head, and the thermal head is punched and stenciled through operation in the main scanning direction. At the same time, the master made by the platen roller or the like is moved in the sub-scanning direction perpendicular to the main scanning direction while moving the master, and the peripheral surface of the cylindrical porous support plate is made of, for example, a resin or a metal net. The mesh screen is wound around a rotatable plate cylinder having a structure in which multiple layers are wound, and ink is supplied to the inner peripheral surface of the plate cylinder from the ink supply means provided inside the plate cylinder. Then, a printing sheet (hereinafter also simply referred to as “sheet”) as an example of a sheet is continuously pressed against a master on the plate cylinder by a pressing unit called a press roller, an impression cylinder, or an intermediate pressing roller. A heat-sensitive digital stencil printing apparatus is known in which printing is performed by pressing ink so that ink is oozed out from the opening of the plate cylinder and the perforated portion of the master, and the ink is transferred to a sheet.
Although the printing drum is sometimes simply referred to as a “plate cylinder”, hereinafter, in this specification, the plate cylinder is assumed to be disposed on the outer periphery of the printing drum, and includes the plate cylinder unless otherwise specified. It is simply called “printing drum”. In addition, “ink” is also referred to as “ink”, but in the following description, the term “ink” will be used as a unified term for ink.

In the above-described stencil printing, recently, double-sided printing, in which printing is performed on both sides of paper, has been frequently performed in order to reduce paper consumption, document storage space, and the like. In this double-sided printing, the paper loaded on the paper feed unit is passed through the printing unit, printed on the front surface, which is one side of the paper, and then the single-sided printed paper is turned over to pass through the printing unit again. The method of printing on the back side, which is the other side, has been adopted, but the work of once-printed single-sided printed paper is set again in the paper feed section, and the paper after single-sided printing is aligned Was troublesome.
Accordingly, the present applicant has proposed a novel stencil type duplex printing apparatus (hereinafter also referred to as “stencil duplex printing apparatus”) that can solve these problems in view of the troublesome work after single-sided printing (for example, patents). Reference 1 and 2).

In recent years, hybrid stencil printing apparatuses have been proposed that combine ink-jet printing apparatuses that can perform color printing relatively quickly and inexpensively in addition to stencil printing that can be printed quickly and inexpensively (see, for example, Patent Documents 3 and 4). ).
A composite image forming apparatus related to a post-processing apparatus including an electrophotographic image forming apparatus and an ink jet recording apparatus has also been proposed (for example, see Patent Document 5).
Further, recently, an image forming apparatus capable of forming an image by a recording method using a method different from the ink jet method and a recording method using the ink jet method and easily accessing a portion where image forming by the ink jet is performed. A technique related to an optional device attached to and detached from an image forming apparatus has also been proposed (see, for example, Patent Document 6).

JP 2003-200355 A Japanese Patent No. 3545861 JP 2002-137514 A JP 2002-137515 A Japanese Patent Laid-Open No. 2002-60072 JP 2006-76043 A

However, conventional stencil double-sided printing apparatuses such as Patent Documents 1 and 2 can print quickly and inexpensively, but functionally only one color can be printed with one printing drum. There have been no choice but to perform overprinting by preparing more than one printing drum, or by preparing a printing machine in which four or more printing drums are arranged in one machine. For this reason, overprinting takes four times longer, and the simultaneous four-color printing machine is expensive and is not realized.
In stencil printing, printing using a master (stencil paper) can be performed quickly and inexpensively. However, because stencil printing is used, variable data printing such as page printing and address printing cannot be supported. It was. For this reason, until now, after stencil printing of the same portion, the variable portion has been printed again by a color printer such as an ink jet method, which has been problematic.

Therefore, the present invention has been made in view of the above-described problems and circumstances, and includes a first printing unit capable of duplex printing, and a sheet feeding unit that feeds a sheet to the first printing unit. By disposing a second printing unit that performs printing with a printing method different from that of the first printing unit, duplex printing including stencil printing and overprinting by the second printing unit can be performed. The main purpose is to realize and provide a duplex printing apparatus.
Another object of the present invention is to realize and provide a double-sided printing apparatus that can perform double-sided printing including double-sided printing including stencil printing and overprinting by inkjet printing, particularly by using the second printing unit as an inkjet printing apparatus. . Another object of the present invention is to realize and provide a double-sided printing apparatus and a stencil printing apparatus that achieve the effects described below.

In order to solve the above-described problems and achieve the above-described object, the invention according to each claim employs the following characteristic means and configuration.
According to the first aspect of the present invention, there is provided a printing drum on which a plate-making master for double-sided printing, in which a first plate-making image and a second plate-making image are formed side by side along the rotation direction thereof, is wound on the printing drum. A first printing unit having ink supply means for supplying ink to the pre-printed master and a pressing means relatively movable to and away from the printing drum; and sheet feeding for feeding the sheet to the first printing unit A feeding unit, a sheet discharging unit that discharges a printed sheet printed by the first printing unit, and a printed image on the surface corresponding to the first plate-making image or the second plate-making image by the first printing unit Temporarily holding the surface-printed sheet on which the sheet is formed, then reversing the sheet toward the first printing unit and re-feeding the sheet, and re-feeding the sheet that has passed through the first printing unit. Part or switching means for guiding to the sheet discharge part In printing apparatus, between the sheet feeding unit and the first printing unit, characterized in that the second printing unit for printing a different printing method from the first printing unit is arranged.

  According to a second aspect of the present invention, in the double-sided printing apparatus according to the first aspect, the second printing unit is an ink jet printing apparatus.

  The invention according to claim 3 is the double-sided printing apparatus according to claim 2, wherein the plate-making image area of each image data corresponding to the first plate-making image and the second plate-making image for double-sided printing is detected, When the value obtained by multiplying the detected value of the plate-making image area and the number of printed sheets is equal to or smaller than a preset value, duplex printing is performed only by the inkjet printing apparatus.

  According to a fourth aspect of the present invention, in the double-sided printing apparatus according to the third aspect, the setting value is variable.

  According to a fifth aspect of the present invention, in the duplex printing apparatus according to any one of the second to fourth aspects, the printing drum constitutes a drum unit that is detachable from the apparatus main body for each ink color. A drum unit ink color identifying means for identifying the ink color of the drum unit, and a stencil printing mode in which stencil printing is executed by the first printing unit; Both of the print modes can be executed, and when overprinting is performed using ink colors of the inkjet printing apparatus other than the ink colors of the drum unit according to image color data, the ink color of the drum unit is changed to the drum unit ink color. Judgment is made based on the ink color identified by the identification means.

  According to a sixth aspect of the present invention, in the double-sided printing apparatus according to the fifth aspect, the determination is performed before the start of printing.

  The invention according to claim 7 is the duplex printing apparatus according to any one of claims 2 to 6, wherein the inkjet printing apparatus feeds a sheet or a surface-printed sheet to the inkjet printing apparatus at a predetermined timing. A sheet conveying path of the re-feeding section is formed extending toward the register means to convey the surface-printed sheet, and the inkjet printing apparatus alone. Both sides printing is possible.

  The invention according to claim 8 is the double-sided printing apparatus according to claim 7, wherein when an edit mode for executing editing of the front or back side print image in the stencil double-sided printing is set, for confirmation of a print image in the edit mode, Printing is performed only by the inkjet printing apparatus.

  According to a ninth aspect of the present invention, in the double-sided printing apparatus according to the eighth aspect, when the editing mode is set, the editing setting value set in the editing mode is additionally printed on a print image only by the ink jet printing apparatus. It is characterized by doing.

  According to a tenth aspect of the present invention, in the double-sided printing apparatus according to the seventh aspect, a stencil double-sided printing mode, an ink-jet double-sided printing mode, and an overlapped double-sided printing mode of stencil printing and ink-jet printing can be set as a printing mode. It is characterized by being.

  According to an eleventh aspect of the present invention, in the double-sided printing apparatus according to any one of the third to tenth aspects, when the position of a printed image by stencil printing is moved and adjusted upstream or downstream of the sheet, the ink jet writing is performed. The start position can be automatically changed in accordance with the position of the printed image by the stencil printing.

  According to a twelfth aspect of the present invention, in the double-sided printing apparatus according to any one of the seventh to eleventh aspects, after the plate-making master for duplex printing is wound around the printing drum, the printing mode is switched. When the inkjet printing mode is selected, duplex printing can be performed only by the inkjet printing apparatus.

  A thirteenth aspect of the present invention is the double-sided printing apparatus according to any one of the second to eleventh aspects, wherein the surface of the resist means is subjected to a fine uneven surface treatment. .

  According to a fourteenth aspect of the present invention, in the double-sided printing apparatus according to the thirteenth aspect, the surface of the sheet conveying means and the sheet guiding means disposed in the refeed portion is subjected to a fine uneven surface treatment. It is characterized by.

  According to a fifteenth aspect of the present invention, there is provided a printing drum on which a master plate for single-side printing is wound, an ink supply means for supplying ink to the master plate master on the printing drum, and a contact and separation relative to the printing drum. A first printing unit having a flexible pressing means, a sheet feeding unit that feeds a sheet to the first printing unit, and inkjet printing disposed between the first printing unit and the sheet feeding unit A stencil printing apparatus comprising: an apparatus for detecting a plate-making image area of image data corresponding to a plate-making image of the plate-making master, and a value obtained by multiplying the detected value of the plate-making image area and the number of printed sheets in advance. When the value is equal to or less than the set value, printing is performed only by the inkjet printing apparatus.

According to the present invention, the above-mentioned problems can be solved and a novel double-sided printing apparatus and stencil printing apparatus can be realized and provided. The effects for each claim are as follows.
According to the first aspect of the present invention, the above configuration enables double-sided printing including double-sided printing including a stencil system and overprinting by the second printing unit.

  According to the second aspect of the present invention, by using the second printing unit as an inkjet printing apparatus, duplex printing including stencil printing and overprinting by inkjet printing can be performed.

  According to the invention described in claim 3, with the above-described configuration, the plate-making image area of each image data corresponding to the first plate-making image and the second plate-making image for double-sided printing is detected to detect the plate-making image area. If the value multiplied by the number of prints is equal to or less than a preset value, the ink consumption of the printing drum is reduced and the master is not used, so that duplex printing is performed using only the inkjet printing device. Becomes cheaper.

  According to the fourth aspect of the present invention, since the setting value is variable, the setting value can be freely changed according to the user's desire. The user can freely set a mode for reducing the amount of supply used.

  According to the invention described in claim 5, with the above configuration, for example, the drum unit may be used by using an ink color other than black as an option in addition to the standard black ink, and the ink color of the drum unit is determined by the drum unit ink color identification means. When the ink color of the drum unit identified by the drum unit ink color identifying means is black, the stencil printing mode by the first printing unit is executed based on the black image color data, and is identified. When the ink color of the drum unit is other than black, it is combined with inexpensive stencil printing without using expensive ink-jet ink by executing the overprint mode by the ink-jet printing apparatus based on image color data other than black. Therefore, inexpensive color double-sided printing can be performed.

  According to the sixth aspect of the present invention, when the ink color of the drum unit identified by the drum unit ink color identifying means is black, the stencil by the first printing unit is based on the black image color data. When the print mode is executed and the ink color of the identified drum unit is other than black, based on the image color data other than black, it is determined that the overlap printing mode by the inkjet printing apparatus is executed before starting the printing. Execution can eliminate printing mistakes.

  According to the seventh aspect of the invention, with the above configuration, double-sided printing can be performed only by the ink jet printing apparatus.

  According to the invention described in claim 8, with the above configuration, the front or back side print image is edited by the first printing unit (for example, the front and back side print image position, the leading edge margin value, the vertical movement setting value, the horizontal movement setting value, When editing mode is set to execute (including scaling setting values, etc.), the above-mentioned editing content can be confirmed on the printed image by printing only with the inkjet printing apparatus, so that the master as a plate is not wasted. Can be prevented.

  According to the invention described in claim 9, when the edit mode is set, the edit set value set in the edit mode is additionally printed on the print image only by the ink jet printing apparatus, whereby the effect of the invention described in claim 8 is achieved. In addition, it is possible to accurately and reliably recognize which value of the edit setting value the user should correct.

  According to the invention described in claim 10, according to the configuration described above, the printing mode can be set by switching to the stencil duplex printing mode, the inkjet duplex printing mode, or the overlapping duplex printing mode of stencil printing and inkjet printing. The printing conditions can be changed according to the printing.

  According to the eleventh aspect of the present invention, when the position of the printed image by stencil printing is moved and adjusted upstream or downstream of the sheet, the ink jet writing start position is also adjusted to the position of the printed image by stencil printing. Thus, it is possible to automatically change the writing start position and perform highly convenient double-sided printing.

  According to the twelfth aspect of the present invention, when the ink jet printing mode is selected by switching the printing mode after winding the plate-making master for double-sided printing around the printing drum according to the above configuration, both sides of the ink jet printing apparatus are selected. It becomes possible to print.

  According to the invention described in claim 13, the surface of the resist means has been subjected to a fine uneven surface treatment, so that, for example, when the image position is corrected by stencil printing, the leading edge margin disappears. In this case, it is possible to prevent the registration roller, for example, as a registration unit from becoming dirty during re-feeding.

  According to the fourteenth aspect of the present invention, the surface of the sheet conveying means and the sheet guiding means disposed in the refeeding portion is subjected to a fine uneven surface treatment, for example, by stencil printing. When the leading edge margin disappears when image position correction is performed, for example, a registration roller as a registration unit, for example, a conveyance roller as a sheet conveyance unit, and a conveyance guide plate surface as a sheet guidance unit are re-feeded. Can be prevented.

  According to the fifteenth aspect of the present invention, with the above-described configuration, a plate-making image area of image data corresponding to a plate-making image of a plate-making master is detected, and a value obtained by multiplying the detected value of the plate-making image area and the number of printed sheets is previously set. When the value is equal to or less than the set value, the ink consumption of the printing drum is reduced and the master is not used, so that it is cheaper to perform printing only with the ink jet printing apparatus.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention (hereinafter referred to as “embodiments”) including the best mode for carrying out the present invention and examples will be described below with reference to the drawings. Constituent elements such as members and components having the same function and shape throughout the embodiment and the modified examples are given the same reference numerals and will not be described after being described once. In order to simplify the drawings and the description, even components that are to be represented in the drawings may be omitted as appropriate without being specifically described in the drawings. When a constituent element such as a published patent gazette is cited and explained as it is, the reference numeral is attached with parentheses to distinguish it from that of each embodiment.

  FIG. 1 shows the overall configuration of a duplex printing apparatus to which a duplex printing apparatus according to the present invention is applied. FIG. 6 shows the overall configuration of a conventional stencil duplex printing apparatus. First, a known stencil type duplex printing apparatus (hereinafter, also referred to as “stencil duplex printing apparatus”) 500 is described with reference to FIG. An embodiment of the apparatus will be described.

  As shown in FIG. 6, a conventional stencil duplex printing apparatus 500 includes a printing unit 20 (hereinafter also referred to as “first printing unit 20”), a plate making unit 40, a paper feeding unit 60, a plate discharging unit 80, and a paper discharge unit. 70, an image reading unit 50 called a scanner, a refeed tray 24, a refeed unit 300, a switching member 17 as switching means, and the like. The structure and functions of the scanner, plate making / plate feeding, plate discharging mechanism, etc., that is, the plate making unit 40, the paper feeding unit 60, the plate discharging unit 80, the paper discharge unit 70, and the image reading unit 50 are conventionally known. Since it is the same as the printing integrated stencil printing apparatus, description of its detailed configuration is omitted (see, for example, Patent Document 1 or Japanese Patent Application Laid-Open No. 2006-224633, FIG. 1).

  In the stencil type double-sided printing apparatus described in Patent Document 1 or Japanese Patent Application Laid-Open No. 2006-224633, at the time of single-sided printing, the master-making master 66 made for single-sided printing is used as the outer peripheral surface of the printing drum 2 (the plate cylinder). The master plate 65 for double-sided printing, in which two plate-making images are made side by side in the rotation direction of the printing drum 2 at the time of double-sided printing, is wound around the outer peripheral portion of the printing drum 2. A plate cylinder (hereinafter also simply referred to as “printing drum 2”) provided is wound around the outer peripheral surface, so that one-side printed paper is rotated by one rotation of the printing drum 2 during single-sided printing, and the printing drum 2 during double-sided printing. In this way, one double-sided printed paper is obtained by one rotation. Since the single-sided printing operation is a well-known operation as in the past, the description thereof is omitted.

  That is, the double-sided printing operation is generally performed in the following steps. In FIG. 6, first, the first sheet P is fed from the sheet-making master 65 for duplex printing wound on the printing drum 2 by feeding the first sheet P from the sheet feeding unit 60. A surface-printed paper PA as a surface-printed sheet is created by pressing the first sheet P with the press roller 13 (also referred to as “A-side image”). The leading edge of the first sheet, which is the front-side printed sheet PA, is peeled off from the printing drum 2 by the switching member 17 at the position indicated by the two-dot chain line in the drawing, and is provided on the passing guide plate 41b so as to be opened and closed. While being clamped by the clamper 41a, it is conveyed in the direction of the arrow Xb, guided to a refeed tray 24 also called an auxiliary tray, and temporarily stopped and held by suction. The first surface printed sheet in this state is referred to as “PB”.

  Next, the second sheet P is fed from the sheet feeding unit 60, and the first plate-making image (A-side image) of the plate-making master 65 and the second sheet P are pressed by the press roller 13. The next front-side printed paper PA is created. The leading edge of the second sheet that has become the front-side printed sheet PA is peeled off from the printing drum 2 by the switching member 17 and then conveyed in the direction of the arrow Xb while being clamped by the clamper 41a of the passing guide plate 41b. It is temporarily stopped and held by suction on the paper feed tray 24. At the time of printing the surface of the second sheet, the sheet refeeding apparatus 300 (refeeding section 300 / refeeding section) is activated, and the first sheet PB from the sheet refeed tray 24 is predetermined. Is pressed against the outer peripheral surface of the press roller 13 by the re-feed roller 47. As a result, the first sheet PB is guided by the guide member 49 and directed toward the printing nip portion of the first printing unit 20 along the outer peripheral surface of the press roller 13 by the rotation and reversal action of the rotating press roller 13. Sent. The first sheet PB is fed at a timing corresponding to a second plate-making image (hereinafter also referred to as “B-side image”) of the plate-making master 65 wound on the printing drum 2. A back printed image is printed by being pressed against the outer peripheral surface of the printing drum 2 by the press roller 13. The first sheet of paper that has been printed on both sides and has become a printed sheet PC is guided by a switching member 17 that is switched to a position indicated by a solid line in the drawing, and is provided on the outer peripheral surface of the printing drum 2 by a peeling claw not shown. The paper is peeled off from above, and is sent to the paper discharge tray 62 of the paper discharge unit 70 by the operation of the paper discharge conveyance unit 27A. Thereafter, this operation is repeated, and one double-side printed sheet is created by one rotation of the printing drum 2.

Since the stencil duplex printing apparatus 500 includes a configuration common to the embodiments described later, the detailed configuration and operation of each part and each member will be supplemented with appropriate reference to FIG.
The printing unit 20 is disposed substantially at the center of the apparatus main body 100, and is a division in which the first plate-making image A and the second plate-making image B are formed side by side along an arrow direction (clockwise direction) in the drawing. It has a printing drum 2 around which a plate-making master 65 for double-sided printing, which is also called a plate-making master 65, is wound, and a press roller 13 as a pressing means that can be brought into contact with and separated from the outer circumference of the printing drum 2. Yes.
The printing drum 2 is rotatably supported by the apparatus main body 100 and is driven to rotate in the arrow direction (clockwise direction) in the figure by, for example, a brushless DC motor as the drum driving unit 121 shown in FIG. In FIG. 1, reference numeral 2A indicated by parentheses together with reference numeral 2 indicating the printing drum includes driving force transmission means such as a gear and a belt for rotating the printing drum 2, the drum driving means, and an ink supply mechanism (not shown). The drum unit is configured to be integrated and unitized for each ink color, and is detachable from the apparatus main body 100 through an attaching / detaching unit (not shown). On the outer peripheral surface of the printing drum 2, a plate-making master 65 punched and made by the plate-making unit 40 on the basis of image information is clamped by a clamper 6 that can be freely opened and closed and wound around.

In the master-making master 65, an A-side image for front side printing and a B-side image for back side printing are formed side by side in the order of rotation of the printing drum 2 (in the circumferential direction). An unprinted portion is formed between the B-side image.
The digital image data that is the basis of the image on the pre-printed master 65 is created by reading an original with the image reading unit 50 or created on a computer such as a personal computer. The document is set by an automatic document feeder (ADF) (not shown), an automatic double-sided document feeder, or a user placing a document on the contact glass. Needless to say, the digital image data may be created by outputting a digital manuscript created on a computer. These digital image data are once stored in an image memory (see image memory 90 in the image processing unit 95 shown in FIG. 5) in an image processing unit, which will be described later, and then sent to the plate making unit 40 to perform punch plate making to the master.

In the vicinity of the outer peripheral surface of the printing drum 2, a rotational position sensor (for example, a home position sensor 134 also shown in FIG. 5) and a rotary encoder are provided as rotational position detecting means for detecting the rotational position (phase) of the printing drum 2. ing.
Inside the printing drum 2 is a well-known ink supply means 61, that is, a single ink supply means 61 composed of an ink roller and a doctor roller or the like that forms a substantially wedge-shaped ink reservoir between the ink rollers. The ink supply means 61 can supply ink to the inner peripheral surface of the printing drum 2, that is, the inner peripheral surface of the plate cylinder.

A press roller 13 is disposed near the lower portion of the printing drum 2. The press roller 13 is made of, for example, nitrile rubber (NBR), which is an elastic body having oil resistance, and at least the outer peripheral surface of the rubber is, for example, a film having a fine uneven surface treatment. For example, glass beads as glassy fine particles and ceramic fine particles, which are the same as those used for preventing smearing of printed matter in an offset printing machine or the like, are uniformly coated or adhered. This minimizes swelling and ink smearing due to contact with the outer peripheral surface of the printing drum 2 or the master-made master 65 on the printing drum 2 or contact with ink on the printed image surface side of the surface printed paper PB. It is comprised so that it may become.
Both ends of the press roller 13 are rotatably supported by an arm member (not shown), and the arm member (not shown) is swingably supported by a press roller contact / separation mechanism (not shown). The press roller 13 selectively occupies a separation position shown in FIG. 1 where the circumferential surface is separated from the printing drum 2 and a pressure contact position where the circumferential surface is pressed against the master-making master 65 on the printing drum 2. Detailed configurations of the press roller contact / separation mechanism and the printing unit 20 are shown in FIGS. 1 to 3 and the like of Patent Document 1 and Japanese Patent Application Laid-Open No. 2006-224633, and are similar to the contents described in the corresponding paragraphs. Is adopted.

Next, a configuration around the known printing pressure range varying means 28 that determines the printing pressure range (pressing range) of the press roller 13 will be briefly described. In the stencil duplex printing apparatus 500, as shown in FIG. 6, the printing pressure as a first printing pressure range pattern that applies printing pressure only to the surface area corresponding to the A-side image in the master-making master 65 on the printing drum 2 is used. Range pattern I, printing pressure range pattern II as a second printing pressure range pattern that applies printing pressure only to the back surface area corresponding to the B-side image in the master-making master 65 on the printing drum 2, and on the printing drum 2 At least three of the printing pressure range pattern III as a third printing pressure range pattern for applying printing pressure from the front surface area to the back surface area corresponding to the single-side plate-making image in the single-side printing master 66 for single-side printing. One of the two printing pressure range patterns can be selectively switched. The printing pressure range variable means 28 for selectively switching one of these three printing pressure range patterns includes a multi-stage cam (43) and a step cam (49) shown in FIGS. The press roller contact / separation mechanism (55) includes a stepping motor (52) that rotationally drives the step cam (49). The printing pressure range varying means 28 also has a configuration / function for displacing the press roller 13 between the printing position and the non-printing position.
The stencil duplex printing apparatus 500 uses a single printing drum 2, a single ink supply means 61, and a single press roller 13, as in the techniques described in Patent Document 1 and Japanese Patent Application Laid-Open No. 2006-224633. Stencil duplex printing can be performed continuously.

  The plate making unit 40 is disposed substantially on the right side of the printing drum 2 and has a known function and configuration for producing the plate-making masters 65 and 66. The detailed configuration of the plate making unit 40 is the same as that shown in FIG. 1 of Patent Document 1 and described in paragraphs “0066” to “0073” corresponding thereto. The drive means including a stepping motor and a thermal head drive circuit that rotationally drive a master conveying means such as a platen roller disposed in the plate making section 40 are collectively referred to as a plate making drive means 124 in FIG.

  The sheet feeding unit 60 is disposed on the lower right side of the plate making unit 40, and in the first printing unit 20 or the second printing unit 5 in the first embodiment described later, as an example of a sheet. It has a function and configuration as a sheet feeding unit that feeds the paper P. The sheet feeding unit 60 includes a sheet feeding tray 61 serving as a sheet feeding table / sheet feeding table, a pickup sheet feeding roller 10a and a separation roller 10b serving as a sheet feeding unit / sheet feeding unit, a separation pad 11, and a resist serving as a registration unit. It is mainly composed of a roller pair 12 and the like.

The pickup paper feed roller 10a and the separation roller 10b are connected by a timing belt, and a paper feed motor comprising, for example, a stepping motor (not shown) as a paper feed driving means via a driving force transmission means such as a timing belt and a timing pulley. It is rotationally driven by.
The registration roller pair 12 includes a pair of driven rollers 12a and a driving roller 12b, which are in pressure contact with each other via a biasing means such as a spring (not shown). The registration roller pair 12 is also rotationally driven by a registration motor including a stepping motor (not shown) as registration driving means via driving force transmission means such as a timing belt and a timing pulley.

The paper feed tray 61 is configured to be able to move up and down with a large number of sheets P stacked thereon. The paper P has a paper size adapted to the size of the A-side image and the B-side image. That is, when the maximum print size at the time of single-sided printing is, for example, A3 size, the maximum print size for double-sided printing is approximately A4 size, and the maximum sheet passing paper is also A4 size. The paper passing direction is the short direction.
The paper feed tray 61 can be moved up and down by a lifting mechanism (not shown). The paper feed tray 61 is provided with a plurality of paper size detection sensors that detect the size of the paper P set on the paper feed tray 61.
Driving means such as a lifting motor, a paper feeding motor, and a registration motor (not shown) are collectively referred to as a paper feeding driving means 125 in FIG.

  The plate discharging unit 80 is disposed on the upper left side of the printing drum 2 and has a known function and configuration for peeling and discharging the used plate-making master 65 on the printing drum 2. The detailed configuration of the discharged plate portion 80 is the same as that shown in FIG. 1 of Patent Document 1 and described in the paragraphs “0078” to “0079” corresponding thereto. The drive means such as a plate release motor and a compression plate drive motor disposed in the plate release portion 80 are collectively referred to as a plate release drive means 126 in FIG.

The paper discharge unit 70 is disposed on the lower left side of the plate discharge unit 80 and has a known function and configuration as a sheet discharge unit that peels off and discharges the paper P printed from the plate-making master 65 on the printing drum 2. . The detailed configuration of the paper discharge unit 70 is the same as that shown in FIG. 1 of Patent Document 1 and described in the paragraph “0081” corresponding thereto.
That is, the paper discharge unit 70 mainly includes a peeling claw (not shown), a paper discharge conveyance unit 27A, a paper discharge tray 62 as a sheet discharge table / discharge table, a peeling fan (not shown), and the like. The tip of the peeling claw is provided so as to be able to approach and separate from the outer peripheral surface of the printing drum 2 by a swinging means (not shown), and has been printed from the outer peripheral surface of the printing drum 2 when occupied in the proximity position. Peel off the paper. The paper discharge conveyance unit 27A is composed of a belt-type suction conveyance device, and includes a driving roller 25b, a driven roller 25a, an endless belt 27 stretched between the driving roller 25b and the driven roller 25a, and a separated print. A suction fan 26 is provided as air suction means for sucking and sucking the used paper onto the endless belt 27. The driving roller 25b is rotationally driven by, for example, a stepping motor as driving means. The paper discharge transport unit 27A transports the printed paper on the upper surface of the endless belt 27 in the direction of arrow Xe in the figure while sucking and adsorbing the paper.

The paper discharge tray 62 has one end fence and one side fence, and the printed sheets are stacked in an orderly manner on the upper surface thereof. The peeling fan is disposed in the vicinity of the upper side of the peeling claw, and finishes the surface printing process by blowing air between the plate-making master 65 on the printing drum 2 and the front end of the printed paper. The paper that is peeled off from the master-making master 65 on the printing drum 2 by the switching member 17 and the leading edge of the paper that is peeled off from the master-making master 65 on the printing drum 2 are lifted by the peeling claw after finishing the back surface printing process. And functions as a blowing separation means for complete peeling.
Drive means (not shown) such as a driving motor and a suction fan 26 for driving the driving roller 25b disposed in the paper discharge section 70 are collectively referred to as a paper discharge drive means 127 in FIG.

An image reading unit 50 (hereinafter, also referred to as “scanner 50”) is disposed on the upper part of the apparatus main body 100 and has a function and configuration for reading image information of a document. The scanner 50 includes a contact glass 52, a pressure plate 51 provided so as to be movable toward and away from the contact glass 52, a reflection mirror and a fluorescent lamp that scans and reads an image of an original, and reflection of the scanned image. A lens 53 that focuses light, an image sensor 54 that includes a CCD that photoelectrically converts the reflected light of the focused image, a plurality of document size detection sensors that detect the size of the document set on the contact glass 52, and the like It has. A known automatic document feeder (hereinafter also referred to as “ADF”) is appropriately mounted on the scanner 50. There is a case where an automatic double-sided document feeder not shown is mounted. The ADF has a document placement table on which a plurality of documents can be placed, and the document placement table is also provided with a document sensor that detects the presence or absence of a document. The drive means such as a scanner motor disposed in the image reading unit 50 are collectively referred to as a read drive means 128 in FIG.
The image reading unit 50 has a configuration having various functions for color separation necessary for multicolor printing, for example, a filter unit that can switchably control a plurality of color filters described in JP-A No. 64-18682. The one having the same function and configuration is disposed on the optical path between the reflection mirror disposed in the image reading unit 50 and the lens 53, and color ink jet printing is performed by the ink jet printing apparatus 30 shown in FIG. It is used when performing.

  The sheet re-feed unit 300 is disposed around the press roller 13 and is provided with a surface-printed paper PA having a printed image formed on the surface corresponding to the first plate-making image A or the second plate-making image B. A refeeding unit (refeeding unit) that includes a refeeding transport unit that transports toward the press roller 13 after being temporarily held, and that is reversed by the press roller 13 and refeeds toward the printing unit 20. ). Hereinafter, it is assumed that a printed image is formed on the surface of the front-side printed paper PA corresponding to the first plate-making image A.

  The paper re-feed unit 300 holds the front end of the surface-printed paper PA, which is fed from the printing unit 20 and printed with the A-side image by the printing unit 20, near the first position (movement position) near the printing unit 20. As a sheet nipping / conveying means that includes an openable / closable clamper 41a that holds the clamper 41a at a second position (initial position or standby position) lower than the moving position and opens the front end of the surface-printed paper PA. Refeeding as a refeeding transport means for temporarily holding the surface-printed paper PB disposed on the passing guide plate 41b and the refeeding tray 24 and transporting it while sucking and sucking it toward the press roller 13 Refeeding that temporarily stops and positions the front end of the surface printed paper PB conveyed by the conveyance unit 42 and the refeed conveyance unit 42 to the press roller 13 Stopper 48, which is a positioning means / refeeding positioning member or stopper member, and the front end of the surface printed paper PB temporarily stopped by the stopper 48 are released at a predetermined timing to release the paper PB. A re-feeding roller 47 as a re-feeding registration means that is displaceable between a contact position where the front end is in contact with and pressed against the press roller 13 and a non-contact position spaced apart from the contact position; 13 is provided near the outer peripheral surface of the press roller 13 on the right side of 13 and the reprinted roller 47 guides the surface-printed paper PB abutted on the outer peripheral surface of the press roller 13 to the nip portion formed in the printing unit 20. It is mainly composed of a refeed guide means and a guide member 49 as a refeed guide member.

The refeed tray 24, the refeed transport unit 42, the refeed roller 47 and the stopper 48 are integrally moved up and down via the contact / separation mechanism of the press roller 13.
The refeed conveyance unit 42 includes a belt-type suction conveyance device, and includes a drive roller 43 that is rotatably supported on a case side plate formed integrally with the refeed tray 24, and is rotatable on the case side plate. And a plurality of endless belts 45 stretched between the driving roller 43 and the driven roller 44, and the surface-printed paper PB on the endless belt 45 with a relatively weak suction force. A suction fan 46 or the like is provided as an air suction means for suction / adsorption. The drive roller 43 is rotationally driven by a transport unit drive motor 122 shown only in FIG. 5, for example, comprising a stepping motor as drive means.
The refeed conveyance unit 42 is the same as the refeed conveyance member (25) shown in FIGS.

The passing guide plate 41b provided with the clamper 41a is the same as the moving guide (81) shown in FIGS. 1 and 5 of JP 2006-224633 A, for example, and also JP 2006-224633 A. The reciprocating movement is performed with the same structure as the moving means (87) shown in FIGS. 7 and 8 of the publication, and the clamper 41a is opened and closed.
The guide member 49 has an arcuate shape as a whole, and its inner peripheral surface is arranged in a non-contact state with the press roller 13 with a predetermined gap of about 0.3 to 1.0 mm from the outer peripheral surface of the press roller 13. For example, it is the same as the recording medium guide means (22) shown in FIGS. 1 and 2 of JP-A-2005-350161.

  The switching member 17 is arranged on the left side of the press contact position between the printing drum 2 and the press roller 13 and on the paper transport path. The switching member 17 is supported by the apparatus main body 100 so as to be able to swing and displace at the downstream end portion in the paper conveyance direction. The switching member 17 is a known displacement driving means (for example, a solenoid 123 shown in FIG. 5 and a spring not shown). The first position indicated by a solid line and the second position indicated by a two-dot chain line in FIG. 1 are selectively occupied.

Based on the above-described configuration, the basic operation of the stencil duplex printing apparatus 500 in the stencil duplex printing mode will be described while appropriately borrowing the conventional configuration of the operation panel 103 shown in FIG. 4 and supplementing the detailed configuration as needed.
The user presses the stencil duplex printing mode key 117 on the operation panel 103 to confirm that the stencil duplex printing mode is in effect by turning on the LED 117a, and then presses the start key 104 to perform stencil printing as in Patent Document 1. After the stencil duplex printing apparatus 500 is in a print standby state, after appropriate test printing, the printing conditions are input by the printing speed setting key 113 and various keys on the operation panel 103, and then the number of prints is input by the ten key 109. Thereafter, when the print start key 105 is pressed, the following double-sided printing operation is performed at the printing speed set by the printing speed setting key 113.
When the print start key 105 is pressed, the paper P is fed by the pick-up paper feed roller 10a, and is separated one by one by the cooperative action of the separation roller 10b and the separation pad 11, toward the registration roller pair 12. Sent. The paper P is temporarily stopped by the pair of registration rollers 12 to correct an oblique shift (skew) and the like, and is then printed between the printing drum 2 and the press roller 13 at a predetermined phase timing with respect to the printing drum 2, that is, printing. It is sent out toward the nip portion of the portion 20. The pickup paper feed roller 10a and the separation roller 10b may be rotated by paper feed driving means such as a dedicated stepping motor as described above, or from a main motor that is the drum driving means 121 of the printing drum 2. The driving force may be received using a sector cam or an electromagnetic clutch.

The front side printed paper PA on which the paper P fed from the paper feeding unit 60 is printed at the nip portion of the printing unit 20 and the A-side image is printed by the printing unit 20 is switched by the switching member 17 that is switched upward. The sheet is guided in the lower left direction in the figure, and is discharged toward the sheet re-feeding tray 24 of the sheet re-feeding unit 300.
The passing guide plate 41b reciprocates in the direction of the arrow Xb at a high speed in accordance with the discharge of the front surface printed paper PA by a driving device (not shown), and clamps and guides the front end portion of the front surface printed paper PA.
The front-side printed paper PA on which the A-side image is printed by the printing unit 20 is nipped by the clamper 41a provided on the passing guide plate 41b, and has already been moved in the lower left direction by the passing guide plate 41b. The paper is guided and transported onto the paper refeed tray 24 in a state where contact with the upper surface of the front surface printed paper PB on the paper refeed transport unit 42 is prevented. The front surface printed paper PB that has been on the refeed tray 24 is transported downstream (rightward in FIG. 1) in the refeed direction Xc by the refeed transport unit 42 that is a belt-type suction transport device. . The front end of the front surface printed paper PB is temporarily stopped by abutting against the stopper 48.

Since the suction force of the suction fan 46 is relatively weak, there is no occurrence of sheet buckling or bending due to an excessive transport force. Alternatively, the driving of the endless belt 45 may be stopped by detecting the butting against the stopper 48. The surface printed paper PB on the refeed tray 24 shown in FIG.
The surface-printed paper PB abutting against the stopper 48 is temporarily waiting in the state shown in FIG. 1, but is sent to the printing drum 2 at a predetermined timing, that is, from the paper feeding unit 60 to the printing unit 20. The paper is fed again at the timing when the leading edge of the front surface printed paper PB is fed into the printing unit 20 following the trailing edge of the A-side image printing paper P. Of course, it goes without saying that an appropriate gap is provided between the rear end of the A-side image printing paper P and the front end of the front-side printed paper PB.
The re-feed roller 47 is supported by a displacement mechanism (not shown) so as to be swingable in the vertical direction (contact / separation with respect to the press roller 13). ), The surface printed paper PB is brought into contact with and pressed against the press roller 13, and the leading edge of the surface printed paper PB is detached from the stopper 48 by the pushing operation of the refeed roller 47 so that the paper can be fed and transported again. become. The press roller 13 is driven to rotate at the same peripheral speed as the peripheral speed of the printing drum 2, and the surface printed paper PB pressed by the refeed roller 47 is transported by receiving the transport force.

The surface-printed paper PB is guided by the guide member 49 from the downstream side of the re-feed roller 47 to the range before the nip formed by the press contact between the printing drum 2 and the press roller 13. The surface-printed paper PB is conveyed in a state where the predetermined fine gap between the press roller 13 and the guide member 49 is in close contact with the press roller 13 and is sent to the nip portion between the printing drum 2 and the press roller 13. The surface-printed paper PB that has been re-fed and entered the nip portion of the printing unit 20 is reversed, with the surface-printed surface just above being the lower surface and the unprinted surface being the upper surface. This time, the B-side image is printed on the upper surface, that is, the non-printed side, by the B area of the master-making master 65. In this way, double-sided printing is performed.
The paper PC on which double-sided printing has been performed is guided substantially horizontally in the left direction in the figure by the switching member 17 which is now switched downward, and Xe in the figure toward the paper discharge tray 62 by the paper discharge transport unit 27A. The paper is conveyed in the direction and discharged while being aligned by the end fence and the pair of side fences. Then, the sheets are stacked on the paper discharge tray 62 in an orderly manner.

(First embodiment)
A double-sided printing apparatus 1 according to a first embodiment of the present invention will be described with reference to FIG. Compared with the conventional stencil duplex printing apparatus 500 shown in FIG. 6, the duplex printing apparatus 1 uses the first printing unit 20 instead of the sheet refeeding unit 300 in the first plate making image A or the second plate making. After temporarily holding the surface-printed paper PA on which the printed image is formed corresponding to the image B, the paper is re-fed as a re-feeding unit that is reversed and re-fed toward the first printing unit 20. The point that the paper feeding unit 3 is used and the point that the second printing unit 5 that performs printing by a printing method different from that of the first printing unit 20 is arranged between the first printing unit 20 and the paper feeding unit 60. Mainly different. Hereinafter, it is assumed that the “surface-printed paper PA” includes paper printed by the second printing unit 5.

  As the second printing unit 5, in addition to the inkjet printing apparatus 30 shown in FIG. 1 (hereinafter, also referred to as “inkjet printing unit 30”), a sublimation thermal transfer printer, a thermal transfer ink ribbon printer, and the like are arranged. Even in the case of single-sided printing or double-sided printing, printing can be performed on the paper P by the second printing unit 5 before printing by the printing drum 2.

  Compared with the refeed unit 300 shown in FIG. 6, the refeed unit 3 removes the passing guide plate 41 b provided with the clamper 41 a and replaces the front end of the front surface printed paper PA. The guide member 29 that is guided toward the tray 24 is provided in the vicinity of the lower left oblique side of the press roller 13, the stopper 48, the refeed roller 47, and the guide member 49 are removed, and the refeed tray 24, the refeed Instead of this, the roller 47, the stopper 48, and the refeed conveyance unit 42 are integrally lifted up and down via a press roller contact / separation mechanism (not shown). A point where the re-feeding registration roller pair 22 is disposed in the vicinity of the downstream side of the re-feeding conveyance unit 42 instead of the point attached and fixed at the position, the stopper 48 and the re-feeding roller 47. Sheet conveyance Sheet conveying path as is, toward the registration roller pair 12 in order to inverting and conveying surface printed sheet PB is that it is formed to extend in the Xd direction in the drawing differs mainly.

The first printing unit 20 is the same as that provided in the stencil duplex printing apparatus 500 shown in FIG. That is, the press roller 13 has a separation position shown in FIG. 1 where the circumferential surface is separated from the printing drum 2, and a plate-making master 65 for double-sided printing on the printing drum 2 or a plate-making master for single-sided printing. And 66 are selectively occupied. This mechanism is the same as that mounted on the stencil double-sided printing apparatus 500, and the detailed configuration of the printing pressure range variable means 28 and the printing unit 20 which are also a press roller contact / separation mechanism (not shown) is disclosed in Patent Document 1 and Japanese Patent Application Laid-Open No. 2006-2006. This is well known in the same manner as the contents shown in FIGS. 1 to 3 of the 224633 gazette and described in the corresponding paragraphs.
As shown in FIG. 1, the refeed tray 24 and the refeed transport unit 42 are attached and fixed at a predetermined position below the press roller 13, and do not swing with the up and down swing operation of the press roller 13. It has become. The guide member 29 is fixed to a stationary member of the apparatus main body 100.

  In the present embodiment, the passing guide plate 41b including the clamper 41a is not an essential configuration and may be omitted. This is because the layout configuration of the refeed unit 3, particularly the layout position of the refeed tray 24 and the sheet conveyance path of the refeed unit 3 has the layout configuration shown in FIG. This is because it is difficult for the trouble to contact the surface-printed paper PB that has been previously transported onto 24 and temporarily stopped. However, if the passing guide plate 41b provided with the clamper 41a is used, the surface-printed paper PA can be re-feeded and transported to the re-feed tray 24 reliably and accurately. Of course.

  The paper feed path of the paper refeed unit 3 is provided in the vicinity of the downstream side of the paper refeed tray 24, and serves as a paper (sheet) transport means for temporarily receiving and holding the front end of the front surface printed paper PB at the nip portion. The reprinted registration roller pair 22, and the surface printed paper PB that is provided between the refeeding registration roller pair 22 and the registration roller pair 12 and is sent from the refeeding registration roller pair 22 is directed to the registration roller pair 12. A sheet (B) provided between the re-feed conveyance roller pair 16 and the re-feed registration roller pair 22 and the re-feed conveyance roller pair 16 for guiding the surface printed paper PB toward the registration roller pair 12 ( A sheet is provided between the first guide member 18 including a guide member 18a and a guide member 18b as a guide unit, and the refeed conveyance roller pair 16 and the registration roller pair 12. A second guide member 19 consisting of a pair of guide members 19a and the guide member 19b as paper (sheet) guide means for guiding towards the printed paper PB the registration roller pair 12 is disposed.

  The refeeding registration roller pair 22 includes a pair of driven rollers 22a (hereinafter also referred to as “refeeding registration roller 22a”) and a driving roller 22b (hereinafter also referred to as “refeeding registration roller 22b”). These are pressed against each other via a biasing means such as a spring (not shown). Similarly, the refeed conveyance roller pair 16 includes a pair of driven rollers 16a (hereinafter also referred to as “refeed conveyance roller 16a”) and a driving roller 16b (hereinafter also referred to as “refeed conveyance roller 16b”). These are pressed against each other via a biasing means such as a spring (not shown). The driving roller 22b is rotationally driven by a driving motor 22c shown only in FIG. Similarly, the drive roller 16b is rotationally driven by a drive motor 16c shown in FIG. 5 only including a stepping motor, for example, via a rotational drive transmission means (not shown).

In the present embodiment, the lower side of the registration roller pair 12 has the second printing unit 5 and the sheet conveyance path of the refeed unit 3 is conveyed with the layout configuration shown in FIG. One of the features is that the surface of the registration roller 12b (drive roller 12b) is subjected to a fine uneven surface treatment.
Although the sheet P conveyed from the sheet feeding unit 60 to the registration roller pair 12 is not printed, the registration roller pair 12 is not soiled by ink or the like even if it is conveyed. Since the surface is printed by the second printing unit (for example, the ink jet printing apparatus 30) and / or the printing drum 2, when the paper is fed again by the registration roller pair 12, some images may become dirty. Usually, pressure is applied between the driving roller 12b (hereinafter also referred to as “registration roller 12b”) and the driven roller 12a (hereinafter also referred to as “registration roller 12a”) of the registration roller pair 12 by a spring or the like. The leading edge of the sheet is prevented from entering between the registration roller pair 12. Accordingly, when the registration roller pair 12 is soiled with ink or the like during re-feeding by the registration roller pair 12, the registration roller pair 12 applies the above-mentioned pressure in a state where the above-described pressure is applied in order to match the front end position of the sheet and the print image position. The sheet 12 is rotated by a registration motor (stepping motor) (not shown) to convey the sheet. At this time, if there is a surface print image on the sheet, the registration roller 12b side may be stained. If the registration roller 12b becomes dirty, it will become dirty by retransferring another sheet P when it is conveyed.

  Therefore, in this embodiment, the surface of the registration roller 12b does not impair the function of the registration roller, and the surface of the roller without transfer of ink by the printed image surface of the surface-printed paper PB or the like is a minute protrusion or a minute uneven shape. For example, glass beads or ceramic fine particles, such as glassy fine particles, which are the same as those used for preventing smearing of printed matter, for example, in an offset printing machine, etc., are uniformly coated or adhered as a surface-treated film. Yes. As a result, the outer peripheral surface of the registration roller 12b is configured to minimize ink stains or the like due to contact with the ink on the printed image surface side of the surface-printed paper PB.

For the following reasons similar to those described above, the surfaces of the re-feeding registration roller 22b, the re-feeding conveyance roller 16b, the guide member 18b, and the guide member 19b disposed in the refeed unit 3 are fine. One feature is that the surface treatment is uneven.
As described above, the surface-printed paper PA is re-fed and conveyed by the re-feeding registration roller pair 22 at a predetermined timing, and further conveyed to the registration roller pair 12 by the re-feeding conveyance roller pair 16. Unlike the registration roller pair 12 described above, the re-feeding registration roller pair 22 does not need to match the sheet position and the print image position, so that it is not necessary to apply pressure unlike the registration roller pair 12. Since the paper position and the print image position are adjusted by the registration roller pair 12 after refeeding, the refeeding registration roller pair 22 and the refeeding conveyance roller pair 16 may have a low conveyance pressure. In some cases, the outer periphery and the surface of the paper registration roller 22b, the refeed conveyance roller 16b, the guide member 18b, and the guide member 19b are contaminated with ink or the like due to contact with the ink on the printed image surface side of the surface printed paper PB. is there.
Therefore, the outer periphery / surface of each of the re-feeding registration roller 22b, the re-feeding conveyance roller 16b, the guide member 18b, and the guide member 19b is used as a film subjected to surface treatment of minute protrusions or minute irregularities. For example, glass beads or ceramic fine particles that are uniformly coated or adhered as glassy fine particles are used.

  Next, the operation will be described. The pickup paper feed roller 10a and separation roller 10b of the paper feed unit 60 are driven to rotate by starting a paper feed motor (not shown) comprising a stepping motor, and then a sheet of paper P is conveyed to the registration roller pair 12 and then printed. The sheet P is fed to the printing nip portion between the printing drum 2 and the press roller 13 in the first printing unit 20 by starting a registration motor (not shown) including a stepping motor in accordance with the rotation timing of the drum 2. Thus, stencil printing on the paper P can be performed in the first printing unit 20, and a printing method different from that of the first printing unit 20 is provided between the first printing unit 20 and the paper feeding unit 60. The second printing section 5 that performs printing (in addition to the ink jet printing apparatus 30 shown in FIGS. 1 and 2, a sublimation thermal transfer printer and a thermal transfer ink printer). In the first printing unit 20 before the stencil printing by the printing drum 2 in either case of the stencil single-side printing by the printing drum 2 or the stencil double-side printing by the second printing unit 5. Overprinting can be performed on the paper P.

(Second Embodiment)
With reference to FIGS. 1 to 5, the duplex printing apparatus 1 according to the second embodiment of the present invention will be described in more detail. In the second embodiment, the second printing unit 5 of the double-sided printing apparatus 1 according to the first embodiment is clarified to be an inkjet printing apparatus 30, and the paper feeding path around the paper feeding path of the refeeding unit 3 is determined. FIG. 5 as a control means for controlling the point where the configuration is clearly defined and the operation panel 103 shown in FIG. The main difference is that the functions and configurations of the control device 129 and the like shown are clearly defined.

  The inkjet printing unit 30 will be described in detail with reference to FIGS. In the ink jet printing unit 30, four line type ink jet printer heads are arranged. 2, the Y (yellow) inkjet printer head 30a, the M (magenta) inkjet printer head 30b, the C (cyan) inkjet printer head 30c, and the Bk (black) inkjet printer head. Each of the inkjet printer heads 30a to 30d is supplied with ink of each color. The four inkjet printer heads 30a to 30d are each provided with an ejection port (nozzle) capable of ejecting and ejecting ink of each color facing downward and arranged in parallel along the paper transport direction Xa.

  FIG. 3 schematically shows the outline of the ink flow of the ink jet printing unit 30 shown in FIG. As shown in the drawing, an ink bottle containing ink of each color, that is, a Y (yellow) ink bottle 31a, an M (magenta) ink bottle 31b, a C (cyan) ink bottle 31c, and a Bk (black) ink. Four dedicated ink bottles for the bottle 31 d are arranged in the apparatus main body 100. Ink pumps 34a to 34d schematically shown corresponding to the respective ink colors are arranged in the ink bottles 31a to 31d of the respective colors, and inks of the respective colors are supplied to the ink jet printers of the respective colors by a command signal from the control means 129. Supply to heads 30a-30d.

  Ink bottles 31a to 31d for the respective colors are provided with ink remaining amount detection sensors 35a to 35d shown in FIG. 5 only as ink remaining amount detecting means corresponding to the respective ink colors. A signal related to the remaining amount of ink of each color detected by the detection sensors 35 a to 35 d is output to the control unit 129. Based on this signal, the remaining amount of ink for each color can be displayed on the display device 120 of the operation panel 103 shown in FIG. Further, when the ink jet printer heads 30a to 30d for the respective colors are cleaned, the waste liquid is collected in one waste liquid tank 33 through the waste liquid pipes 32a to 32d for the respective colors. The waste liquid tank 33 is also provided with a waste ink full sensor 36 shown in FIG. 5 only, and outputs a signal related to the ink full state to the control means 129. Based on this signal, the waste liquid full state can be displayed on the display device 120 of the operation panel 103.

  As shown in FIGS. 1 and 2, an inkjet transport unit 14 </ b> A is disposed below the inkjet printing unit 30. The ink jet transport unit 14A includes a drive roller 14b, a driven roller 14a, an endless belt 14c as a paper transport member (sheet transport member) spanned between the drive roller 14b and the driven roller 14a, and suction as air suction means. And a fan 15 or the like. The drive roller 14b is rotationally driven by a transport unit drive motor 14d composed of, for example, a stepping motor shown in FIG.

  With reference to FIG. 4, the operation panel of the duplex printing apparatus 1 will be described. In FIG. 1, an operation panel 103 provided on the upper front surface of the duplex printing apparatus 1 has a start key 104, a print start key 105, a test printing key 106, a continuous key 107, a clear / upper key 107 on its upper surface as shown in FIG. Stop key 108, numeric keypad 109, enter key 110, program key 111, mode clear key 112, printing speed setting key 113, four-direction key 114, paper size setting key 115, stencil duplex printing key 117, stencil single-sided printing mode key 118, It includes a display device 119 composed of a 7-segment LED (light emitting diode), a display device 120 composed of an LCD (liquid crystal display device), and the like.

The start key 104 is pressed when the duplex printing apparatus 1 performs the plate making operation. When the start key 104 is pressed, the plate making operation is performed after the plate discharging operation and the document reading operation are performed, and then the plate making operation is performed. Is performed, and the duplex printing apparatus 1 enters a print standby state. In addition, when the start key 104 is pressed when the duplex printing apparatus 1 performs an inkjet printing operation, the start key 104 functions as an operation activation setting unit that activates an inkjet printing operation in a predetermined mode in addition to the plate making operation.
The print start key 105 is pressed when the duplex printing apparatus 1 performs a stencil printing operation or an inkjet printing operation. The print start key 105 is pressed after the duplex printing apparatus 1 enters a print standby state and various printing conditions are set. As a result, a stencil printing operation, an ink jet printing operation or an overprinting operation in a predetermined mode is performed.
The trial printing key 106 is pressed when causing the duplex printing apparatus 1 to perform trial printing. When various conditions are set and the trial printing key 106 is pressed, only one stencil printing, inkjet printing, or overprinting operation is performed. Is done. The continuous key 107 is pressed before the start key 104 is pressed when continuously performing the plate making operation and the stencil printing operation. After the continuous key 107 is pressed, the start key 104 is pressed after the printing conditions are input. Then, the printing operation is performed following the plate discharging operation, the document reading operation, and the plate making operation.

The clear / stop key 108 is pressed when the operation of the duplex printing apparatus 1 is stopped or when the numerical value is cleared, and the numeric keypad 109 is used for numerical value input. The enter key 110 is used to set a numerical value or the like during various settings, the program key 111 is pressed to register or call a frequently used operation, and the mode clear key 112 is used to clear various modes. This is pressed when returning to the initial state.
The printing speed setting key 113 is pressed when setting the printing speed prior to the stencil printing operation, the ink jet printing operation, or the overprinting operation, and when it is desired to obtain a dark image or when the ambient temperature is low, the printing speed is set. If the user wants to obtain a thin image, or if the ambient temperature is high, the printing speed is set high. The four-way key 114 has an up key 114a, a down key 114b, a left key 114c, and a right key 114d. When adjusting the image position during image editing or when selecting a numerical value or item at various settings, etc. Pressed.

The paper size setting key 115 is pressed when an arbitrary paper size is input, and the paper size input with the paper size setting key 115 has priority over the paper size detected by the paper size detection sensor 73.
The stencil duplex printing mode key 117 functions as a stencil duplex printing mode setting unit that causes the duplex printing apparatus 1 to perform a stencil duplex printing operation. When the stencil duplex printing mode is set, the stencil duplex printing mode key 117 is depressed before the start key 104 is depressed. When the duplex printing mode key 117 is pressed, the LED 117a disposed in the vicinity thereof is lit to display to the user that the stencil duplex printing mode is in effect. Similarly to the stencil duplex printing mode key 117, the stencil simplex printing mode key 118 also functions as a stencil simplex printing mode setting means for causing the duplex printing apparatus 1 to execute a stencil simplex printing operation, and a start key 104 is used when setting the stencil simplex printing mode. When the stencil single-sided printing mode key 118 is pressed, the LED 118a arranged in the vicinity thereof is lit to indicate to the user that the stencil single-sided printing mode is selected. In the duplex printing apparatus 1, the LED 118a is lit in the initial state, and the stencil single-sided printing mode is set.
The stencil printing mode in which stencil printing is executed by the first printing unit 20 includes a stencil double-sided printing mode and a stencil single-sided printing mode.

In the present embodiment, in addition to the setting means for setting the stencil printing mode, an inkjet single-sided printing mode key 135 as an inkjet single-sided printing mode setting means for causing the double-sided printing apparatus 1 to execute an inkjet single-sided printing operation only by the inkjet printing unit 30. An inkjet double-sided printing mode key 136 as an inkjet double-sided printing mode setting unit that causes the duplex printing apparatus 1 to perform an inkjet double-sided printing operation only by the inkjet printing unit 30; An overlap double-sided printing mode key 137 as an overlapping double-sided printing mode setting unit for causing the double-sided printing apparatus 1 to execute a double-sided double-sided printing operation in which the stencil double-sided printing by the printing unit 20 is overlaid. And overprint mode key 138 of the overprinting operation of repeating the stencil sided printing by the first printing unit 20 as overprint mode setting means for executing the double-sided printing apparatus 1 is provided in addition to the surface printing.
The inkjet single-sided printing mode key 135, the inkjet double-sided printing mode key 136, the overlapping double-sided printing mode key 137, and the overlapping printing mode key 138 each have a built-in LED inside each key, and each key is pressed once for each mode. Is set, the corresponding LED is lit to notify the user. When each key is pressed twice, the setting of each mode is canceled and the LED is turned off.
In addition to the above, in the overlap duplex printing mode, in addition to the inkjet single-side printing by the inkjet printing unit 30 and the stencil duplex printing by the first printing unit 20 and the inkjet double-side printing by the inkjet printing unit 30 In addition, the case where the stencil single-sided printing by the first printing unit 20 is overlapped is included. These mode settings have a control configuration that is set, for example, by continuously pressing the corresponding key.

  As described above, in the present embodiment, a stencil printing mode (including a stencil double-sided printing mode and a stencil single-sided printing mode) in which stencil printing is performed by the first printing unit 20 and an inkjet single-sided printing mode only by the inkjet printing unit 30 are used. In addition, an ink-jet double-sided printing mode, a stencil single-sided printing or a stencil double-sided printing, a superposition printing mode in which a superposition printing operation is executed in the ink jet printing unit 30 and a superposition double-sided printing mode can be set and executed.

  The stencil duplex printing mode key 117, the stencil simplex printing mode key 118, the inkjet single-sided printing mode key 135, the inkjet double-sided printing mode key 136, the overlapping duplex printing mode key 137, and the overlapping printing mode key 138 are not limited to those described above. It may be provided individually by a touch panel method, switched by a single switching dial method, or set by sequentially changing the LED display every time one key is pressed.

A display device 119 composed of a 7-segment LED mainly displays numbers such as the number of printed sheets. The display device 120 made up of an LCD has a hierarchical display structure. By pressing the selection setting keys 120a, 120b, 120c, and 120d provided below the display device 120, changing to various modes such as scaling and position adjustment is performed. And the setting in each mode is possible. Further, the display device 120 displays the status of the double-sided printing device such as “can be made / printed” as shown in the figure, as well as an alarm such as plate-making or discharge jam, paper feed or paper discharge jam, printing paper, A supply instruction of a supply such as a master and ink is also displayed. Note that, using the selection setting keys 120a, 120b, 120c, and 120d, a stencil printing mode (including a stencil double-sided printing mode and a stencil single-sided printing mode), an inkjet single-sided printing mode and an inkjet double-sided printing mode, an overprinting mode, It is also possible to set the overlapped duplex printing mode or the editing mode to be executable.
Here, the edit mode refers to the alignment of the front side print image, the rear side print image, and other front and back sides of the double sided printing, leading edge margin, and vertical movement when executing the editing of the front side or back side printed image in stencil duplex printing. It means a broad concept including editing of setting values, left / right movement setting values, scaling setting values, and the like.
When the front-side print image is aligned or the back-side print image is aligned when the edit mode is set, the display device 120 of the operation panel 103 is shown, for example, in FIG. 5 of JP-A-2006-76270. It is possible to switch to a display screen similar to the “image position adjustment mode”.

FIG. 5 shows a control configuration of the duplex printing apparatus 1. In the block diagram of the figure, the control means 129 includes a CPU 130, a ROM 131, a RAM 132, and a known microcomputer having a timer (not shown), and is provided inside the apparatus main body 100.
Based on various signals from the operation panel 103 and the image processing unit 95 as an image processing apparatus, detection signals from various sensors provided in the apparatus main body 100, operation programs called from the ROM 131, and related data. 1 printing unit 20, plate making unit 40, image reading unit 50, paper feeding unit 60, paper discharge unit 70, driving units provided in the plate discharging unit 80, ink pumps 34 a to 34 d provided in the ink jet printing unit 30, The operation of the transport unit drive motor 14d and the suction fan 15 is controlled, and the operation of the drive motors 16c and 22c, the transport unit drive motor 122, the suction fan 46, etc. provided in the refeed unit 3 or the operation panel 103 is controlled. The display devices 119 and 120 and the image processing unit 95 are controlled, and the operation of the entire duplex printing device 1 is controlled.

  Here, the image processing unit 95 is a device that includes a function of sorting the image data read by the image reading unit 50 into those used in the first printing unit 20 and those used in the inkjet printing unit 30. For example, it has the same configuration as the image processing apparatus (37) shown in FIG. 6 of JP-A-2006-76270. That is, common print image data read by the image reading unit 50 and commonly used by the first printing unit 20 and the inkjet printing unit 30 is predetermined by a common image data processing device (not shown) provided in the image processing unit 95. Is sent to a thermal head drive control device (not shown) of the plate making unit 40 via an image forming unit selection means (not shown) provided in the image processing unit 95, and this data is processed. On the basis of the above, each heating element of the thermal head is selectively heated to perform perforating plate making on the master.

  On the other hand, the variable image data sent from the computer such as the personal computer 101 is subjected to predetermined image processing by a variable image data processing device (not shown) provided in the image processing unit 95, and then the image forming unit selecting means. To the ink jet printer head drive control device (not shown) of the ink jet printing unit 30, and based on this data, the ink jet printer heads 30 a to 30 d selectively eject ink to form an image. It is configured. Alternatively, variable image data sent from a variable data recording memory (not shown) in which necessary image data is recorded in advance is provided in the image processing unit 95, and the inkjet printer head is driven via the image forming unit selection means. The ink jet printer heads 30a to 30d are configured to perform image formation by selectively ejecting ink based on the data sent to the control device. The image reading unit 50 is also connected to the image processing unit 95. The personal computer 101 is connected to the image processing unit 95.

  The ROM 131 stores an operation program and related data of the entire duplex printing apparatus 1, and the operation program and related data are appropriately called by the CPU 130. The RAM 132 has a function of temporarily storing calculation results of the CPU 130, a function of storing data signals and on / off signals set and input from various keys and various sensors on the operation panel 103 as needed. The control means 129 also grasps the rotational position of the printing drum 2 based on a home position signal from the home position sensor 134 and a signal from an encoder (not shown) provided in the drum driving means 20.

  Next, the operation of the main part of the duplex printing apparatus 1 will be described. First, an inkjet single-sided printing operation will be described. The user replenishes paper of the paper size to be used in the paper feed tray 61 or sets a document to be printed on the contact glass 52 or an ADF document table (not shown), and then prints with various keys on the operation panel 103. The conditions are set, and then the inkjet single-sided printing mode key 135 is pressed to set the inkjet single-sided printing mode. Next, after confirming that the inkjet single-sided printing mode is in the inkjet single-sided printing mode key 135 by the user, the user presses the start key 104. When the start key 104 is pressed, the image data of the document is read by the image sensor 54 of the image reading unit 50, and the read image data is transmitted to the image processing unit 95 to perform the above-described image processing.

On the other hand, after one appropriate test print (this operation is omitted), the print condition is input using the print speed setting key 113 and various keys on the operation panel 103, the number of prints is input using the ten key 109, and the print start key is input. When 105 is pressed, the following ink jet single-sided printing operation is performed at the printing speed set by the printing speed setting key 113.
When the print start key 105 is pressed, in FIG. 1, one separated sheet P is sent toward the registration roller pair 12 in the same manner as the stencil single-sided printing operation. The paper P is temporarily stopped by the registration roller pair 12 and then sent to the ink jet printing unit 30 in accordance with the timing of ink jet print image formation in the ink jet printing unit 30. The sheet P sent by the registration roller pair 12 is conveyed while being sucked and held by the endless belt 14c by the suction force of the suction fan 15, and the leading end thereof is detected by a sheet detection sensor (not shown) provided near the inlet of the inkjet printing unit 30. When detected, the data processed by the image processing unit 95 is sent to an inkjet printer head drive control device (not shown) of the inkjet printing unit 30. The ink jet printer heads 30a to 30d are operated based on the sent data, and an ink jet print image is formed on the surface of the paper P. The ink jet transport unit 14 </ b> A sucks and transports the paper Pa (surface printed paper PA) on which the ink jet print image is formed, and transports the surface printed paper PA between the printing drum 2 and the press roller 13.

In the ink jet single-sided printing operation and the inkjet double-sided printing operation described later, as a matter of course, stencil printing is not performed in the first printing unit 20, and therefore the first printing unit 20 is in an inoperative state. That is, the printing drum 2 occupies the home position and is in a rotation stopped state, and the press roller 13 is held at the separation position shown in FIG. 1 by turning off the solenoid (not shown) of the printing pressure range variable means (press roller contact / separation mechanism) 28. It remains.
The transport direction of the paper Pa transported by the ink jet transport unit 14A is switched by the switching member 17 on the paper transport path. During single-sided printing by the inkjet printing apparatus 30, the switching member 17 occupies the first position indicated by the solid line, and the paper Pa is guided by the switching member 17 to the paper discharge transport unit 27A in the paper discharge unit 70, and is not shown in the drawing claw. As a result, the leading end of the paper Pa is peeled off from the outer peripheral surface of the printing drum 2, sucked and conveyed by the endless belt 27 that runs in the direction of the arrow Xe (paper discharge direction) in the figure, and sequentially discharged and stacked on the paper discharge tray 62.

  Next, an inkjet double-sided printing operation will be described. In substantially the same manner as the ink jet single-sided printing operation, the user replenishes paper of the paper size used in the paper feed tray 61, or sets a plurality of documents to be printed on the contact glass 52 or on an ADF document table (not shown). After that, the printing conditions are set by using various keys on the operation panel 103, and then the inkjet duplex printing mode key 136 is pressed to set the inkjet duplex printing mode. Next, after confirming that the inkjet double-sided printing mode is in the inkjet double-sided printing mode key 136 by the user, the user presses the start key 104. When the start key 104 is pressed, the image sensor 54 of the image reading unit 50 continuously reads the image data of the original document (image data for the front side print image and image data for the back side print image). The image data is transmitted to the image processing unit 95 and the above-described image processing is performed. Note that the image data for the back printed image is temporarily stored in an image memory 90 as an image data storage unit provided in the image processing unit 95.

On the other hand, after one appropriate test print (this operation is omitted), the print condition is input using the print speed setting key 113 and the various keys on the operation panel 103, and then the number of prints is input using the numeric keypad 109. When the start key 105 is pressed, the following inkjet double-sided printing operation is performed at the printing speed set by the printing speed setting key 113.
When the print start key 105 is pressed, the first sheet P separated into one sheet by the sheet feeding means in the same manner as the ink jet single-sided printing operation in FIG. Thereafter, the image is sent to the inkjet printing unit 30 in accordance with the timing of forming the inkjet surface print image. The paper P sent by the registration roller pair 12 is conveyed while being sucked and held by the endless belt 14c by the suction force of the suction fan 15, and when the leading end is detected by the paper detection sensor, it is processed by the image processing unit 95. The data for forming the surface print image is sent to an ink jet printer head drive control device (not shown) of the ink jet printing unit 30. The ink jet printer heads 30 a to 30 d are operated based on the sent data, and a front surface print image is formed on the paper P. The ink jet conveyance unit 14A sucks and conveys the paper Pa (surface printed paper PA) on which the surface print image is formed by the ink jet printing unit 30, and conveys the paper Pa between the printing drum 2 and the press roller 13 which are in an inoperative state. .

  The conveyance direction of the paper PA conveyed by the inkjet conveyance unit 14A is switched by the switching member 17. At the time of double-sided printing by the inkjet printing unit 30, the switching member 17 occupies the second position indicated by a two-dot chain line, and the surface printed paper PA is switched by the switching member 17 that is switched upward, and the device of the switching member 17 Guided between a guide member (not shown) fixed to the main body 100 and the guide member 29, guided between the guide member and the guide member 29 and guided toward the refeed tray 24 in the Xb direction in the figure, Further, the sheet is sucked and conveyed by the refeeding conveyance unit 42 and temporarily held and stopped by the refeeding resist roller pair 22.

  During this time, the second sheet P separated by the sheet feeding means is temporarily stopped by the registration roller pair 12 through the same operation as described above, and then at the timing of forming the inkjet surface print image. Together, it is sent to the inkjet printing unit 30. The surface print image forming data processed by the image processing unit 95 is sent to an ink jet printer head drive control device (not shown) of the ink jet printing unit 30, whereby the ink jet printer heads 30 a to 30 d are operated, and the surface The print image is formed on the second sheet P. The inkjet conveyance unit 14A sucks and conveys the second sheet Pa (representing the surface-printed sheet PA) on which the surface print image is formed, between the print drum 2 and the press roller 13, and conveys the sheet by the switching member 17. The direction can be switched. The second surface-printed paper PA is guided by the switching member 17 switching upward, and between the guide member and the guide member 29, and passes between the guide member and the guide member 29. The paper is guided to the paper refeed tray 24 in the middle Xb direction, and is further sucked and transported by the paper refeed transport unit 42 and temporarily held and stopped by the refeed resist roller pair 22.

Although the description will be mixed, the first front-side printed paper PB that has been temporarily stopped by the re-feeding registration roller pair 22 is transferred to the registration roller pair 12 when the re-feeding registration roller pair 22 starts to rotate. In the drawing, the sheet is fed again and reversely conveyed by the pair of refeeding conveyance rollers 16 that are rotated while being guided by the first guide member 18 and further guided by the second guide member 19. It is conveyed toward the registration roller pair 12 in the Xd direction, and is temporarily stopped at the nip portion of the registration roller pair 12.
The reversed first surface printed paper PB is temporarily stopped by the registration roller pair 12 and then sent to the ink jet printing unit 30 in accordance with the timing of forming the ink jet back surface printed image. The first surface-printed paper PB sent by the registration roller pair 12 is conveyed while being sucked and held by the endless belt 14c by the suction force of the suction fan 15, and when the leading end is detected by the paper detection sensor, The data for forming the back side printed image processed by the image processing unit 95 is sent to an ink jet printer head drive control device (not shown) of the ink jet printing unit 30, whereby the ink jet printer heads 30 a to 30 d are operated and reversed. A back printed image is formed on the top surface (back surface) of the first printed sheet PB. The ink jet transport unit 14 </ b> A sucks and transports the first inkjet double-side printed paper PC on which the back side printed image is formed by the ink jet printing unit 30, and transports it between the printing drum 2 and the press roller 13 that are in an inoperative state. To do. The first inkjet double-side printed paper PC is guided to the paper discharge conveyance unit 27A in the paper discharge unit 70 by the switching member 17 which is switched downward (first position), and the paper PC of the paper PC is separated by a peeling claw not shown. The front end portion is peeled off from the outer peripheral surface of the printing drum 2, sucked and conveyed by the endless belt 27 that runs in the direction of the arrow Xe in the drawing, and sequentially discharged and stacked on the discharge tray 62.

  Next, the overlapping printing operation (or the overlapping single-sided printing operation) will be described. The user replenishes paper of the paper size to be used in the paper feed tray 61 or sets a plurality of documents to be printed on the contact glass 52 or an ADF document table (not shown), and then various keys on the operation panel 103. Then, the printing conditions are set, and then the overlap printing mode key 138 is pressed to set the overlap printing mode. Next, when the user confirms the overlap printing mode by turning on the LED built in the overlap printing mode key 138 and then presses the start key 104, the overlap printing operation is started. In the overlap printing operation, after the inkjet single-sided printing operation performed in the same manner as described above, the same stencil single-sided printing operation as described above is continuously performed, whereby the inkjet single-sided printed image by the inkjet printing unit 30 is performed. The stencil single-sided printing image is printed by the first printing unit 20 in a superimposed manner, and can be easily understood and carried out by those skilled in the art from the description of the inkjet single-sided printing operation and the stencil single-sided printing operation described above. Therefore, further explanation is omitted.

  Next, the overlapping double-sided printing operation will be described. The user replenishes paper of the paper size to be used in the paper feed tray 61 or sets a plurality of documents to be printed on the contact glass 52 or an ADF document table (not shown), and then various keys on the operation panel 103. Then, the printing conditions are set, and then the overlapping duplex printing mode key 137 is pressed to set the overlapping duplex printing mode. Next, when the user confirms that it is the overlapped duplex printing mode by turning on the LED built in the overlapped duplex printing mode key 137 and then presses the start key 104, the overlapped duplex printing operation starts. The overlapping double-sided printing operation is performed by performing the stencil double-sided printing operation continuously after the ink-jet double-sided printing operation performed in the same manner as described above, thereby superimposing the first on the inkjet double-sided printed image by the inkjet printing unit 30. This is an operation for printing a stencil duplex printing image by the printing unit 20 of the printer, and from the above description of the ink jet duplex printing operation and the stencil duplex printing operation, those skilled in the art can easily understand and implement it. Is omitted.

  As described above, by arranging the inkjet printing unit 30 as described above, stencil single-sided printing by the printing drum 2 in the first printing unit 20 in either case of single-sided printing or double-sided printing by the inkjet printing unit 30; Before the stencil duplex printing, the inkjet printing unit 30 can perform printing on the paper P and the surface-printed paper PB by the inkjet printing unit 30. The inkjet printing unit 30 may be a single color, but by arranging the color inkjet printing unit 30 as described above, in addition to the stencil single-sided printing and the stencil double-sided printing by the printing drum 2 in the first printing unit 20, the second Overprinting by the color ink jet printing unit 30 can be performed in the printing unit 5.

Hereinafter, in addition to the first embodiment and the above-described operation example under the control of the control unit 129, an operation example that can be executed by the double-sided printing apparatus 1 according to the present embodiment will be described while supplementing necessary configurations as appropriate.
(First operation example)
In the stencil duplex printing mode by the first printing unit 20 and the overlapping printing mode by the inkjet printing unit 30, that is, when the overlapping duplex printing mode is set, ink colors other than the ink color of the printing drum 2 (drum unit 2A) of the image color data are inkjet printed. Sometimes, the plate-making image area of each image data corresponding to the first plate-making image (A-side image) and the second plate-making image (B-side image) for duplex printing to be wound on the printing drum 2 is controlled. A detection means (CPU 130) (not shown) in the means 129 calculates and detects the plate-making image area, compares a value obtained by multiplying the detected value and the number of printed sheets with a set value set in advance in the ROM 131, and sets it. If the value is less than the value, printing is automatically changed to the inkjet double-sided printing mode.
The set value is the plate-making image area of each image data corresponding to the A-side image and the B-side image (for example, in the image data of a predetermined size corresponding to the master plate-making size, black of the white pixel data signal and the black pixel data signal). When the ink consumption used in the printing drum 2 is predicted by using a value obtained by multiplying the number of pixel data signals) and the number of prints, that is, a value corresponding to the total print image area, and duplex printing is performed by inkjet printing. Only when printing with stencil printing ink is cheaper than stencil printing, stencil printing at the plate making unit 40 and stencil printing at the first printing unit 20 are performed. The above set values are related data and data tables previously set in the ROM 131 by experiments or the like (settings corresponding to the ink consumption set in accordance with the detection / counting of black pixel data signals and the number of printed sheets for each paper size) Value).
The set value may be set in consideration of conditions that make it cheaper, including the cost of using the master, for stencil duplex printing. The set value can be changed (variable). is there. In this way, the setting value can be set freely by the user in consideration of conditions such as the cost setting of the stencil ink and master and the presence or absence of the stencil printing time when using stencil printing. The user may be able to set a setting for shortening the printing time or a mode for reducing the amount of supply used such as stencil ink or master.

  As described above, in the first operation example, the control unit 129 (CPU 130) causes the first plate-making image and the second plate-making image for double-sided printing stored in the image memory 90 when the overlapping double-sided printing mode is set. A pre-set value stored and pre-stored in the ROM 131 is a value obtained by detecting and measuring the plate-making image area of each image data corresponding to the above and multiplying the detected value of the plate-making image area by the number of prints set with the numeric keypad 109 In the following cases, the paper feed drive means 124 of the paper feed section 60 and the drive means of the ink jet print section 30 (ink pumps 34a to 34d, transport unit drive motor) so as to perform duplex printing only with the ink jet printing apparatus 30. , Suction fan 15), solenoid 123 of switching member 10 and each driving means of refeed unit 3 (various drive motors 16c and 22c, transport unit drive) Over data 122, having a suction fan), and a function of controlling the discharging driving section 127 of the paper output unit 70.

(Second operation example)
When the stencil duplex printing mode is set in the duplex printing apparatus 1, the printing conditions are set using the edit mode, and the front side printing image registration, the back side printing image registration, and other double sided printing front and back, leading edge margins, vertical movement When setting values, left / right movement setting values, scaling setting values, and the like are set, it is impossible to determine whether the print condition settings for duplex printing are correct unless printing is actually executed to check the image position. In the past, after setting the printing conditions for double-sided printing, plate making and trial printing were performed to determine whether it was correct. Therefore, if it is correct, it is sufficient to continue printing. However, if an incorrect setting is made, it is necessary to remake the plate after resetting the printing conditions. In some cases, this operation was repeated in order to set the user as expected. The master as a plate was wasted because plate making was performed each time. Therefore, in this operation example, in order to determine whether the printing condition setting was correct without wasting the plate, instead of forming the stencil printing image, ink jet printing was performed only by the ink jet printing unit 30. Confirmation is performed using an inkjet print.

  As described above, in the second operation example, the control unit 129 (CPU 130), when setting the stencil double-sided printing mode, based on the editing mode setting signal for executing the editing of the front or back side printed image in the stencil double-sided printing. For the confirmation of the print image in the edit mode, the paper feed drive means 124 of the paper feed section 60 and the drive means of the ink jet print section 30 (ink pumps 34a to 34d, transport unit drive) so that duplex printing is performed only by the ink jet printing apparatus 30. Motor, suction fan 15), solenoid 123 of switching member 10, drive means (various drive motors 16 c, 22 c, transport unit drive motor 122, suction fan) of refeed unit 3, and paper discharge drive of paper discharge unit 70 It has a function of controlling the means 127.

(Third operation example)
In addition to the second operation example, in this operation example, the edit setting value for duplex printing is set by inkjet printing on the inkjet duplex printing image so that the printing condition setting can be confirmed and corrected without wasting the plate. It is something to print. When printing conditions are set using a duplex printing editing mode to set the alignment of the front surface print image, the alignment of the back surface print image, etc., the plate making is performed based on the setting at the time of plate making. When printing is actually performed and the image position is confirmed, it may be difficult to determine which value of the set value should be corrected. Therefore, the edit setting value used for plate making is superimposed on the print image of only the inkjet printing apparatus 30 to print the edit setting value for duplex printing.
As described above, in the third operation example, based on the edit mode setting signal, the control unit 129 (CPU 130) additionally prints the edit setting value set in the edit mode on the print image using only the inkjet printing apparatus. As described above, it mainly has a function of controlling each driving means (ink pumps 34a to 34d, transport unit drive motor, suction fan 15) of the inkjet printing unit 30.

(Fourth operation example)
As described in detail in the second embodiment, any one of the six mode keys arranged on the operation panel 103 is selected and set, and any one of the six types of print modes is selected. It is feasible.
For example, if you want to print all the two-sided originals in single color with stencil printing, press the stencil double-sided printing mode key 117 to select and set the stencil double-sided printing mode. Can be printed. For example, when it is desired to perform ink-jet color printing for all of the double-sided color originals, when the ink-jet double-sided printing mode is selected and set by pressing the ink-jet double-sided printing mode key 136, the double-sided color originals can be printed in color as the originals.
Further, when stencil printing of the back side data of the double-sided document is performed by the printing drum 2 in the first printing unit 20 and color printing is desired by the inkjet printing unit 30 in the second printing unit 5, stencil printing and inkjet printing are performed. By selecting the printing mode, the back surface data can be printed at a low cost by the printing drum 2, and the front surface data can reduce contamination that may occur at the time of refeeding due to printing by the inkjet printing unit 30.

(Fifth operation example)
In the third and fourth operation examples, the image data for the pre-printed master wound around the printing drum 2 and the other image data are divided to be printed by the ink jet printing unit 30, and the plate making and printing are performed. In the middle of printing or during additional printing, the duplex printing condition setting is set to the inkjet duplex printing mode by depressing the inkjet duplex mode key 136 to set the inkjet duplex printing mode. At this time, printing is performed only by inkjet printing without operating the press roller 13.
Of course, if the duplex printing condition setting is set to stencil printing and inkjet printing mode during printing or during additional printing, stencil printing and inkjet printing modes are obtained.
As described above, in the fifth operation example, the control unit 129 (the CPU 130) winds the master plate 65 for duplex printing around the printing drum 2, and then switches from the inkjet duplex mode key 136 by switching the printing mode. On the basis of the signals relating to the inkjet printing mode, the sheet feeding drive means 124 of the sheet feeding section 60 and the respective drive means (ink pumps 34a to 34d, transporting) of the inkjet printing section 30 so that duplex printing is performed only by the inkjet printing apparatus 30. Unit drive motor, suction fan 15), solenoid 123 of the switching member 10, each drive means (various drive motors 16 c, 22 c, transport unit drive motor 122, suction fan) of the refeed unit 3, and discharge of the paper discharge unit 70. It has a function of controlling the paper driving means 127.

(Sixth operation example)
In stencil duplex printing, the printing drum 2 constitutes the drum unit 2A in the printing mode stencil printing and the ink jet overlap printing mode, and can be attached to and detached from the apparatus main body 100, and other than black by using an optional drum. The ink can be used for printing. Therefore, the ink color of the printing drum 2 can be determined on the printing drum 2 by the color identification signal of the drum unit 2A. Here, a specific example of the color identification means (detection means) of the drum unit 2A will be described.

  As described above, the printing drum 2 constitutes a drum unit 2A that is unitized with an ink container and an ink supply pump (not shown). It can be attached and detached with. For example, the printing drum 2 loaded with the optional red ink and the printing drum 2 loaded with the standard black ink are set separately, and each is detachably attached to the apparatus main body 100 via the attaching / detaching means. It is configured. As a specific example of an attaching / detaching mechanism or attaching / detaching mechanism (not shown) for selectively attaching / detaching the red ink printing drum 2 and the black ink printing drum 2 to / from the apparatus main body 100, for example, Sho 61 Examples are the same as the plate cylinder support device shown in FIGS. 1 to 4 of Japanese Patent No. -85462, which is adopted. In addition, for example, holding means (36), gripping frame (50), front frame (51), and rear frame shown in FIG. 2 and FIG. (52) or the like may be used.

A drum ink color detection sensor (not shown) as drum ink color identification means for detecting whether the drum unit 2A for red ink or the drum unit 2A for black ink is arranged in the apparatus main body 100 in the vicinity of the attaching / detaching means. It is installed. As a specific example of the drum ink color detection sensor, for example, a combination of an electrical connector (for example, male) disposed on the drum unit 2A side and an electrical connector (for example, female) disposed on the apparatus main body 100 side, The difference is electrically detected and judged. This is the same as the drum unit ink type identification sensor (51) shown in FIG. 5 of JP-A-2006-281658.
The drum ink color identification means is not limited to the drum ink color detection sensor described above. For example, the hall element sensor (136, 137, 138) shown in FIG. It may be detected in combination with magnets (130, 131, 132) arranged in the drum unit 2A.

  Since the ink color of the printing drum 2 of the standard stencil duplex printing apparatus is black, the master plate is made based on the black data of the image color data, the pre-printed master is printed on the winding drum 2 and other images are printed. By printing the color data with the ink jet printing unit 30, double-sided printing can be performed in which an inexpensive color print can be obtained by combining with inexpensive stencil printing without using expensive ink jet ink.

  As described above, in the sixth operation example, the control unit 129 (CPU 130) uses the ink colors of the inkjet printing unit 30 other than the ink colors of the drum unit 2A according to the image color data processed by the image processing unit 95. When overprinting, the ink color of the drum unit 2A is determined by the ink color identified by the drum unit ink color identification means.

(Seventh operation example)
As described in the sixth operation example, the ink color of the printing drum 2 of the standard stencil duplex printing apparatus is black. However, if the drum unit is replaced and the optional drum unit is installed and printing starts, There is a possibility that unnecessary printing may be performed because the printing of different colors is performed. Further, since the printing drum 2 must be set again and reprinted, paper, ink, and time are wasted. Therefore, in this operation example, the ink color of the drum unit 2A is confirmed before printing is started, the ink color of the drum unit 2A at the time of plate making is compared with the ink color of the drum unit 2A before printing is started, and printing can be started in the same case. However, in the case of different ink colors, the printing operation by the first printing unit is prohibited, and warning notification / display is performed on the display device 120 of the operation panel 103.

  As described above, in the seventh operation example, in addition to the functions in the sixth operation example, the control unit 129 (CPU 130) determines the ink color of the drum unit 2A by the ink color identified by the drum unit ink color identification unit. Judgment is executed before the start of printing, and as a result of the judgment, the ink color of the drum unit 2A at the time of plate making is compared with the ink color of the drum unit 2A before the printing is started. In the case of the ink color, it has a function of controlling the display device 120 of the operation panel 103 so as to perform warning notification / display to that effect and prohibiting the printing operation by the first printing unit.

(Eighth operation example)
The inkjet printing unit 30 is moved by the inkjet movement mechanism (not shown) by the same movement amount as the movement amount of the printing drum 2 when the image position correction is performed during single-sided or double-sided printing. As a result, the inkjet printing unit 30 moves in the same manner as the printing drum 2 so that the inkjet printing image does not shift. However, the inkjet printing unit 30 is moved by the inkjet moving mechanism to align the image mechanically. It is difficult to get accuracy. As an example of the inkjet moving mechanism, for example, a known mechanism including a guide rail, an inkjet printer head holding unit, a head moving motor, a lead screw, a head home position sensor, and the like can be given.
Therefore, in this operation example, the line type ink jet printer head 30a to 30d used for the ink jet printing unit 30 is a line type ink jet having a wide print width so that printing can be performed with an image moving range larger than the maximum print paper width. Using the printer head, the normal print position is printed at a position where there is no image movement. When the image position on the print drum 2 side is moved, the print start position is moved according to the movement amount, and the print position is moved. Let As a result, even if the printing drum 2 moves, the ink jet printed image is not shifted by moving the writing start position of the line type ink jet printer head in accordance with the moving amount.

  As described above, in the eighth operation example, when the control unit 129 (CPU 130) moves and adjusts the position of the print image by stencil printing upstream or downstream of the paper, the write start positions by the ink jet printer heads 30a to 30d are also set. It has a function of controlling the operation timing of the ink pumps 34a to 34d of the ink jet printing unit 30 so as to automatically change the writing start position in accordance with the position of the printed image by stencil printing.

(Third embodiment)
The present invention is not limited to the double-sided printing apparatus 1 shown in FIG. 1. For example, the sheet refeeding unit 3 and the sheet conveyance path through which the sheet refeeding unit 3 and the registration roller pair 12 are inserted are removed from FIG. 5 is a stencil single-sided printing device having a configuration in which the paper refeeding unit 3 and the printing pressure range variable means 28 are removed, that is, a printing drum 2 around which a master-making master 66 for single-sided printing is wound A first printing unit 20 having an ink supply unit 61 that supplies ink to the master 66 and a press roller 13 as a pressing unit that is relatively movable toward and away from the printing drum 2, and a sheet on the first printing unit 20 A stencil printing apparatus (having a sheet feeding unit (sheet feeding unit) 60 for feeding (sheet) P and an inkjet printing apparatus 30 disposed between the first printing unit 20 and the sheet feeding unit 60 ( Combined type (hybrid) hole To the printing apparatus), it is also possible to apply a control configuration and operation example of the same following the first operation example.
In addition to the stencil single-sided printing operation in the double-sided printing apparatus 1 shown in FIG. 1, the following control configuration and operational example similar to the first operational example are also obtained during overprinting of the single-sided printing operation by the inkjet printing apparatus 30. It is also possible to apply.
That is, a plate-making image area of image data corresponding to the plate-making image of the plate-making master 66 for single-sided printing is detected, and a value obtained by multiplying the detected value of the plate-making image area and the number of printed sheets is equal to or less than a preset set value. In this case, printing is performed only by the ink jet printing apparatus 30.

  As described above, the present invention has been described with respect to specific embodiments and operation examples. However, the technical scope disclosed by the present invention is limited to those exemplified in the above-described embodiments and operation examples. However, those skilled in the art can configure various embodiments, modifications, and examples according to the necessity and application within the scope of the present invention. it is obvious.

It is a schematic front view of the whole duplex printing apparatus showing the first and second embodiments of the present invention. It is a schematic front view which expands and shows the inkjet printing part and 1st printing part periphery in the double-sided printing apparatus of FIG. It is a schematic diagram which shows the flow of the ink of the inkjet printing part of FIG. It is a top view of the operation panel of the double-sided printing apparatus of FIG. It is a block diagram which shows the control structure of the whole double-sided printing apparatus which concerns on 1st and 2nd embodiment. It is a schematic front view which shows the whole conventional stencil duplex printing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Duplex printing apparatus 2 Printing drum 2A Drum unit 3 Refeeding part (refeeding part)
5 Second printing unit 6 Clamper 13 Press roller (pressing means / pressing member)
14A Inkjet transport unit 16 Re-feed transport roller pair (sheet transport means)
17 Switching member (switching means)
18 First guide member (sheet guide means)
19 Second guide member (sheet guide means)
20 First printing unit 22 Re-feeding registration roller pair (sheet transport unit / re-feed transport unit)
24 Refeed tray (Refeed section)
27A Paper Discharge Transport Unit 30 Inkjet Printing Units / Inkjet Printing Devices 30a-30d Inkjet Printer Heads 31a-31d for Each Color Ink Bottles 34a-34d for Each Color Ink Pump 40 for Each Color 40 Plate Making Unit 50 Image Reading Unit 60 Paper Feeding Unit (Sheet Feeding) Part)
61 Paper Tray (Sheet Feeder / Paper Feeder)
62 Output tray (sheet output tray / output tray)
65 Pre-printed master for double-sided printing 66 Pre-made master for single-sided printing 70 Paper discharge unit (sheet discharge unit)
80 Plate removal unit 90 Image memory (image data storage means)
95 Image processing unit (image processing device)
100 Device Main Body 103 Operation Panel (Operation Unit)
120 display device (notification means, display means)
129 Control means 130 CPU
P paper (an example of a sheet / sheet-like recording medium or printing medium)
PA, PB Front surface printed paper PC Double-side printed paper Xa Paper transport direction (sheet transport direction)
Xb Refeed direction (Refeed direction)
Xc Refeed direction (Refeed direction)
Xd Refeed direction (Refeed direction)
Xe Paper discharge direction (sheet discharge direction)

Claims (15)

A printing drum around which a pre-printed master for double-sided printing, in which the first plate-making image and the second plate-making image are formed side by side along the rotation direction, and ink is supplied to the pre-made master on the printing drum A first printing unit having an ink supply unit to perform and a pressing unit relatively movable to and away from the printing drum, a sheet feeding unit to feed a sheet to the first printing unit, and a first printing A sheet discharge section for discharging a printed sheet printed by the printing section, and a surface printed sheet on which a printed image is formed on the surface corresponding to the first plate-making image or the second plate-making image by the first printing section Is temporarily held and then re-feeded by reversing toward the first printing unit, and the sheet that has passed through the first printing unit is guided to the re-feeding unit or the sheet discharge unit. A double-sided printing apparatus comprising switching means for
A double-sided printing apparatus, wherein a second printing unit that performs printing by a printing method different from that of the first printing unit is disposed between the first printing unit and the sheet feeding unit. The double-sided printing apparatus according to claim 1,
The double-sided printing apparatus, wherein the second printing unit is an inkjet printing apparatus. The double-sided printing apparatus according to claim 2,
A plate-making image area of each image data corresponding to the first plate-making image and the second plate-making image for duplex printing is detected, and a value obtained by multiplying the detected value of the plate-making image area and the number of printed sheets is set in advance. If the value is equal to or less than the set value, the duplex printing apparatus performs duplex printing only with the inkjet printing apparatus. The double-sided printing apparatus according to claim 3.
The double-sided printing apparatus, wherein the set value is variable. The double-sided printing apparatus according to any one of claims 2 to 4,
The printing drum constitutes a drum unit that is detachable from the apparatus main body for each ink color,
A drum unit ink color identifying means for identifying the ink color of the drum unit;
Both the stencil printing mode in which stencil printing is performed by the first printing unit and the overprinting mode in which overprinting is performed in the inkjet printing apparatus in addition to the stencil printing can be performed,
When overprinting other than the ink color of the drum unit using the ink color of the ink jet printing apparatus according to the image color data, the ink color of the drum unit is determined by the ink color identified by the drum unit ink color identifying means. A double-sided printing apparatus characterized by that. The double-sided printing apparatus according to claim 5, wherein
The double-sided printing apparatus is characterized in that the determination is performed before printing is started. The double-sided printing apparatus according to any one of claims 2 to 6,
A resist unit disposed on the upstream side of the inkjet printing apparatus for feeding a sheet or a surface-printed sheet to the inkjet printing apparatus at a predetermined timing;
A sheet conveying path of the refeeding portion is formed to extend toward the registration means to convey the surface printed sheet;
A duplex printing apparatus capable of duplex printing only with the inkjet printing apparatus. The double-sided printing apparatus according to claim 7,
A duplex printing apparatus, wherein when an edit mode for executing editing of a front or back printed image in the stencil duplex printing is set, printing is performed only by the inkjet printing apparatus for checking a print image in the edit mode. The double-sided printing apparatus according to claim 8,
When the editing mode is set, the double-sided printing apparatus additionally prints the editing setting value set in the editing mode on a print image only by the inkjet printing apparatus. The double-sided printing apparatus according to claim 7,
A double-sided printing apparatus capable of setting a stencil double-sided printing mode, an inkjet double-sided printing mode, and an overlapping double-sided printing mode of stencil printing and inkjet printing as the printing mode. The double-sided printing apparatus according to any one of claims 3 to 10,
When the position of the print image by stencil printing is moved and adjusted upstream or downstream of the sheet, the writing start position by the inkjet is automatically changed in accordance with the position of the print image by stencil printing. A double-sided printing apparatus capable of being used. The double-sided printing apparatus according to any one of claims 7 to 11,
After winding the plate-making master for double-sided printing on the printing drum, when the inkjet printing mode is selected by switching the printing mode, duplex printing is possible only with the inkjet printing apparatus. Double-sided printing device. The double-sided printing apparatus according to any one of claims 2 to 11,
A double-sided printing apparatus, wherein the surface of the resist means is subjected to a fine uneven surface treatment. The double-sided printing apparatus according to claim 13.
A double-sided printing apparatus, wherein the surface of the sheet conveying means and the sheet guiding means disposed in the refeeding section is subjected to a fine uneven surface treatment. A first printing drum having a printing master for single-sided printing, an ink supply means for supplying ink to the printing master on the printing drum, and a pressing means that can be moved toward and away from the printing drum. Stencil printing apparatus comprising: a printing section; a sheet feeding section that feeds a sheet to the first printing section; and an ink jet printing apparatus disposed between the first printing section and the sheet feeding section. Because
When the plate-making image area of the image data corresponding to the plate-making image of the plate-making master is detected, and a value obtained by multiplying the detection value of the plate-making image area and the number of printed sheets is equal to or less than a preset value, A stencil printing apparatus that performs printing only with the ink jet printing apparatus.

Images