JP2006224633A - Double-sided printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that the position of a sheet at the starting time of making the sheet abut against a press roller by a re-feed register roller fluctuates and cannot be registered correctly due to slight deflection of the leading end of the sheet because the leading end of the sheet is pushed from the rear side and can be deformed when the leading end of one side printed sheet is made to abut against a stopper member and stopped, particularly in stencil printing, wherein a thin sheet paper such as a plain paper, a thick paper such as a postcard and the like each having a different strength are used as printing paper. <P>SOLUTION: A controller 100 (a CPU 101) changes the conveying speed of a conveyor belt 108 of a paper re-feeding conveying device 104 according to kinds of paper and also changes the timing of stopping the conveyor belt 108 after the leading end of the one side printed paper 36a abuts against the stopper member 53. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a duplex printing apparatus, and more particularly to a duplex printing apparatus including a duplex stencil printing apparatus and the like.

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 stencil master (hereinafter simply referred to as “master”) is brought into contact with the heat generating element of the thermal head, and the thermal head is punched and stenciled through the operation in the main scanning direction. A master transporting means such as a platen roller moves the master (hereinafter, sometimes referred to as “a master that has been prepressed”) in the sub-scanning direction (master transporting direction) perpendicular to the main scanning direction, for example, resin Alternatively, a mesh screen made of a metal mesh body is wound around a porous cylindrical rotatable plate cylinder having a structure in which multiple layers are wound, and is provided inside the plate cylinder. Ink is supplied from the ink supply member to the master made on the plate cylinder on the plate cylinder, and the plate on the plate cylinder is pressed by a press means called a press roller, an impression cylinder, or an intermediate press roller (hereinafter referred to as “press roller”). Printing paper (hereinafter simply referred to as “paper”) as an example of a sheet-like recording medium is directly and continuously pressed against the finished master, and ink is oozed out from the opening portion of the plate cylinder and the perforation portion of the master. 2. Description of the Related Art A thermal digital stencil printing apparatus that performs printing by transferring to paper is known. Also known is a stencil transfer printing apparatus for transferring ink that has oozed from the opening portion of the plate cylinder to a transfer cylinder having a rubber sheet and then printing it indirectly on paper (see, for example, Patent Document 1).
Note that the “plate cylinder” is sometimes simply referred to as a printing drum or a plate cylinder disposed on the outer periphery of the printing drum. I will call it.

In the above-described stencil printing, in addition to single-sided printing that prints only on one side of the paper, in recent years, printing is performed on both front and back sides of the paper for the purpose of reducing paper consumption and document storage space. Double-sided printing has come to dominate. As a conventional double-sided printing method / method, using a stencil printing apparatus or the like that performs normal single-sided printing as described above, the paper stacked on the paper feeding unit is passed through the printing unit, and one side of the paper ( Double-sided printed matter by printing over the printed paper that has been printed on the front side and then discharged and stacked on the paper discharge tray, etc., and then passing through the printing section again and printing on the remaining side (back side) of the printed paper Is what you get. In this double-sided printing method, since the printing is performed twice, or since it is necessary to increase the waiting time until the ink of the single-sided printed matter after the single-sided printing is sufficiently dried and set to a so-called set state, The printing time has become very long, and the work of neatly arranging the single-sided printed matter and the setting of the single-sided printed matter again in the paper feeding unit has been very troublesome.
In order to improve the conventional double-sided printing method with manual operation as described above, a double-sided printing device capable of automatically performing double-sided printing has been actively developed, and there are several types of double-sided printing devices. Proposed.

For example, Japanese Patent Application Laid-Open No. 2003-266906 has referred to the conventional double-sided printing method as being roughly divided into six. In other words, two plate cylinders face each other and can be printed on both sides of the paper in one pass. (1) The two-drum facing type one-pass simultaneous duplex printing method can increase the size of the device, and supports printing when printing on one side. In order to prevent ink transfer from the plate cylinder on one side, there is a restriction such as mounting a masterless master, and the master is wasted and the operation is troublesome. For example, see Patent Document 2).
The other five types of double-sided printing methods can be broadly divided into (2) stock refeeding type 2-pass double-sided printing method after single-sided printing (see, for example, Patent Document 3), and (3) two-drum facing type. Transfer cylinder intervening one-pass simultaneous double-sided printing method (for example, see Patent Document 4), (4) 1-drum divided printing simultaneous reversal type double-sided printing method (for example, see Patent Document 5), (5) 1-drum divided printing transfer cylinder There is a one-pass duplex printing method (see, for example, Patent Document 6).
Therefore, although there are restrictions on the paper size and paper type, (6) the above problems (1) to (5) can be solved as a whole, and single-sided printing can be performed without using a useless master. An innovative one-step double-sided printing apparatus capable of obtaining a printed matter with good image quality during double-sided printing and further suppressing an increase in installation space, that is, the double-sided printing method (4) is a basic method (however, A press roller as a single pressing means and a single ink supply means are selected) (hereinafter referred to as "one drum 1 pressing means double-sided printing method or one plate cylinder 1 pressing means double-sided printing method") and paper A new and inexpensive double-sided printing apparatus has been proposed and tried to solve the problem of lack of reliability and reliability of conveyance and high-speed printing compatibility (see, for example, Patent Documents 7 to 9).

  This is because, as disclosed in Japanese Patent Application Laid-Open No. 2003-200355, etc., the master of one plate that is wound around a single plate cylinder is divided into two for front side printing and for back side printing. Then, the paper is re-feeded by skillfully utilizing the paper reversing / conveying action by the rotation of a single pressing means (especially a press roller having a diameter smaller than the outer diameter of the plate cylinder), and divided into two parts on the plate cylinder. In this method, double-sided printing is performed while continuously pressing the back surface, which is the unprinted surface of the front surface-printed paper (one-side printed paper), to any one of the masters that have been subjected to plate making.

JP-A-6-48014 JP-A-6-71996 JP 7-81202 A JP-A-8-118774 JP-A-9-95033 JP-A-10-129100 JP 2003-200355 A JP 2003-266906 A JP 2004-224479 A

  In the double-sided printing apparatus disclosed in Japanese Patent Application Laid-Open No. 2003-200355 and the like, predetermined re-feeding stop means (for reversing the surface-printed paper to be passed through in order to align the resist and correct skew etc.) In the above publication, it corresponds to a refeeding positioning member), and once the leading edge of the paper is stopped, it is slightly changed by a refeeding conveyance device (corresponding to a refeeding conveyance member in the publication) as a refeeding conveyance means. And then stopped, and then a paper re-feeding registration roller as a paper re-feeding registration means provided in a stopper member arrangement portion as a paper re-feeding stopping means (corresponding to a paper re-feeding registration member in the above publication) ) Is brought into contact with the press roller that is rotating at a predetermined timing, and is sent to the printing unit while being reversed by the rotary conveying operation of the press roller. Printing is performed.

  However, in special stencil printing, the type of paper used for printing varies from thin paper such as reprint paper to thick ones such as postcards, which have different strengths (so-called “stretch strength”). Therefore, when the front end of the surface-printed paper is brought into contact with the stopper member and stopped, the front end of the paper is deformed in such a manner that it is pushed from the rear, and the front end of the paper slightly bends to refeed. There is a problem in that the position of the leading edge of the paper at the time of starting contacted with the press roller by the registration roller varies, and the resist deteriorates when double-sided printing is performed.

  Therefore, the present invention provides a double-sided printing apparatus which can perform double-sided printing inexpensively and easily using a one-plate cylinder 1-pressing means double-sided printing method, and has a good resist with little misalignment of print image positions. This is the main purpose.

In order to solve the above-described problems and achieve the above object, the present invention employs the following means / invention specific matters (hereinafter referred to as “configuration”) in the invention of each claim. Is.
According to the first aspect of the present invention, a plate-making master for one plate for double-sided printing in which two first and second plate-making images are formed side by side along the rotation direction of the plate cylinder is wound. A printing unit having a printing cylinder and a pressing unit that is relatively movable toward and away from the printing cylinder, a paper discharge unit that discharges paper printed in the printing unit, and a first plate-making image in the printing unit Alternatively, after temporarily holding the surface-printed paper having the print image formed on the surface corresponding to the second plate-making image, the paper is transported toward the pressing unit and is reversed by the pressing unit to the printing unit. In the double-sided printing apparatus comprising: a paper refeeding unit that refeeds the paper toward the paper, and a switching unit that guides the paper that has passed through the printing unit to the paper refeeding unit or the paper discharge unit. , Temporarily holding the surface-printed paper and transporting it toward the pressing means A paper transporting means, and a paper refeeding stop means for temporarily stopping the front end of the surface-printed paper transported by the paper refeeding transport means before delivering it to the pressing means. And a control means for changing the transport speed of the re-feed transport means.
Here, “the front end of the front surface printed paper” in “before the front end of the front surface printed paper is transferred to the pressing means” is the “rear end” for the first unprinted paper, The front-side printed paper is referred to as the “leading end” in the direction in which it is conveyed (refer to FIG. 4 and FIG. 5, etc., which are the same and represent the embodiments described later). Further, “before passing to the pressing means” is synonymous with “at a position where it can be transferred to the pressing means”.
As a specific example of the “control means”, a control circuit may be used in addition to a microcomputer as in an embodiment of the invention described later (the same applies hereinafter).

  According to a second aspect of the present invention, a plate-making master for one plate for double-sided printing in which two first and second plate-making images are formed side by side along the rotation direction of the plate cylinder is wound. A printing unit having a printing cylinder and a pressing unit that is relatively movable toward and away from the printing cylinder, a paper discharge unit that discharges paper printed in the printing unit, and a first plate-making image in the printing unit Alternatively, after temporarily holding the surface-printed paper having the print image formed on the surface corresponding to the second plate-making image, the paper is transported toward the pressing unit and is reversed by the pressing unit to the printing unit. In the double-sided printing apparatus comprising: a paper refeeding unit that refeeds the paper toward the paper, and a switching unit that guides the paper that has passed through the printing unit to the paper refeeding unit or the paper discharge unit. , Temporarily holding the front-side printed paper and transporting it toward the pressing means A paper transporting means, and a paper refeeding stop means for temporarily stopping the front end of the surface-printed paper transported by the paper refeeding transport means before delivering it to the pressing means. And a control unit that changes a conveyance stop timing of the re-feed conveyance unit after the front end of the front-side printed paper contacts the re-feed stop unit.

  According to a third aspect of the present invention, a plate-making master for one plate for double-sided printing in which two first and second plate-making images are formed side by side along the rotation direction of the plate cylinder is wound. A printing unit having a printing cylinder and a pressing unit that is relatively movable toward and away from the printing cylinder, a paper discharge unit that discharges paper printed in the printing unit, and a first plate-making image in the printing unit Alternatively, after temporarily holding the surface-printed paper having the print image formed on the surface corresponding to the second plate-making image, the paper is transported toward the pressing unit and is reversed by the pressing unit to the printing unit. In the double-sided printing apparatus comprising: a paper refeeding unit that refeeds the paper toward the paper, and a switching unit that guides the paper that has passed through the printing unit to the paper refeeding unit or the paper discharge unit. , Temporarily holding the front-side printed paper and transporting it toward the pressing means A paper transporting means, and a paper refeeding stop means for temporarily stopping the front end of the surface-printed paper transported by the paper refeeding transport means before delivering it to the pressing means. And a control means for changing the transport stop timing of the refeed transport means after the front end of the front-side printed paper contacts the refeed stop means. It is characterized by having.

According to a fourth aspect of the present invention, in the double-sided printing apparatus according to the first, second, or third aspect, the type of the paper is set according to at least one of the thickness and strength of the paper. Features.
According to a fifth aspect of the invention, in the double-sided printing apparatus according to any one of the first to fourth aspects, the paper type setting means for setting the type of the paper is provided.
According to a sixth aspect of the present invention, in the double-sided printing apparatus according to any one of the first to fifth aspects, the paper type detecting means for detecting the type of the paper is provided.

  According to a seventh aspect of the present invention, in the duplex printing apparatus according to any one of the first to sixth aspects, the double-sided printing apparatus is disposed in the vicinity of the refeed stop means and temporarily stopped by the refeed stop means. And a re-feeding registration unit that releases the stopped state of the printed surface-printed paper at a predetermined timing and brings the printed surface-printed paper into contact with the pressing unit.

According to the present invention, it is possible to provide a novel double-sided printing apparatus by solving the problems and problems of the conventional double-sided printing apparatus as described above. The main effects are as follows.
According to the present invention, by including the control unit that changes the conveyance speed of the refeed conveyance unit according to the type of the sheet, for example, when the sheet is thin and light, the conveyance speed of the refeed conveyance unit is slowed down. As a result, the transport speed of the re-feed transport means is controlled so as to minimize the deflection of the surface printed paper after contact with the re-feed stop means (for example, the stopper member or the re-feed positioning member) It is possible to obtain a double-sided printed matter in which the deformation of the front end portion of the surface-printed paper is suppressed and resist deterioration without image positional deviation is suppressed.

  According to the present invention, according to the present invention, by including the control unit that changes the conveyance stop timing of the refeed conveyance unit after the front end of the front surface printed sheet comes into contact with the refeed stop unit, for example, If the paper is thin and light, the paper with the surface printed after the refeed stop means comes into contact by advancing the stop timing of the paper refeed means after the paper refeed stop means comes into contact with the front printed paper. By controlling the conveyance stop timing of the re-feed conveyance means so as to minimize the bending caused by the paper being fed excessively, it is possible to suppress the deformation of the leading edge of the front-side printed paper and to prevent the image position deviation. It is possible to obtain a double-sided printed product in which the deterioration of the resist without suppression is suppressed (claim 2).

  According to the present invention, the transport speed of the re-feed transport means is changed according to the type of the paper, and the transport of the re-feed transport means after the front end of the surface printed paper comes into contact with the re-feed stop means. By having a control means for changing the stop timing, for example, when the paper is thin and light, the transport speed of the re-feed transport means is slowed, and the front end of the printed paper is re-started after contacting the re-feed stop means. By shortening the feeding stop timing of the paper feeding / conveying means, the deflection of the surface printed paper after contacting the refeeding stopping means is minimized, and the surface printing after contacting the refeeding stopping means is performed. By controlling the conveyance speed and conveyance stop timing of the re-feed conveyance means so as to minimize the deflection caused by the excessive feeding of the printed paper, the leading edge of the surface printed paper is further deformed. Surely Te, image misalignment without resist deterioration can be obtained suppressed to double-sided printed material more reliably (claim 3).

  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.

(First embodiment)
First, an overall configuration of a double-sided stencil printing apparatus 300 as an example of a double-sided printing apparatus to which the first embodiment of the present invention is applied will be described with reference to FIG.
As shown in FIG. 1, the double-sided stencil printing apparatus 300 includes a plate-making unit 15 for making a master 8 placed in the upper left side of FIG. 1 and wound in a roll shape, and a master-making master arranged at a substantially central portion in FIG. The plate cylinder 1 is wound around the outer peripheral surface, the ink supply means for supplying ink to the master made on the plate cylinder 1 to be described later, and the outer peripheral surface of the plate cylinder 1 can be brought into and out of contact with the outer peripheral surface. The printing unit 16 having a press roller 21 or the like as a pressing means for pressing the paper 36 against the plate-making master, and the used master on the plate cylinder 1 disposed opposite to the plate-making unit 15 with the plate cylinder 1 interposed therebetween are peeled and discharged. A plate discharging unit 17 that is disposed below the plate discharging unit 17, a sheet feeding unit 30 that feeds a sheet 36 on a sheet feeding tray 35 serving as a sheet feeding table toward the printing unit 16, and the sheet feeding unit 30. Opposed to the bottom of the plate making section 15 and printed A sheet discharge unit 19 that peels the sheet 36 from the plate cylinder 1 and discharges the sheet 36 to a sheet discharge tray 172 as a sheet discharge table, and as shown in FIG. 12, the plate cylinder 1, the plate making unit 15, and the plate discharge unit 17 (in FIG. 12). The image of the original 133 transported from the original receiving tray 134 or placed on the contact glass 135 as the reading unit is disposed on the upper part of the main body frame 130 as the apparatus main body in which both are omitted). An image reading unit 18 that reads an image such as a document (not shown) is provided.
Further, the double-sided stencil printing apparatus 300 temporarily holds the surface-printed paper on which the printed image is formed on the surface thereof as described later, and then directs the surface-printed paper toward the press roller 21. A refeeding unit 48 that is reversed by the delivery press roller 21 and refeeds toward the printing unit 16, and a sheet that has passed through the printing unit 16 (surface-printed paper or double-sided printed paper) And a switching guide 46 as switching means for guiding to the paper discharge unit 19.

1 to 8, the refeed unit 48 includes a front end portion including the front end of the front surface printed paper 36 a sent out from the printing unit 16 (hereinafter sometimes referred to as “front end”) in the vicinity of the printing unit 16. The surface is held at the initial position P2 (or standby position P2) as the second position in the vicinity of the upstream side of the refeeding means 45 lower than the movement position P1. A moving guide 81 as a sheet clamping means (sheet holding means) for releasing the leading end of the printed sheet, and a moving means 87 for reciprocating the moving guide 81 between the moving position P1 and the initial position P2 as shown in FIG. As shown in FIG. 8, when the movement guide 81 occupies the movement position P1, the movement guide 81 is opened once and then operated so as to clamp the front end of the surface printed paper. Occupying initial position P2 The release cam 98 and the release pin 99 constituting the operation timing control means for operating the movement guide 81 so as to open the front end of the surface printed paper, and the movement guide 81 as shown in FIGS. Re-feeding that temporarily holds the surface-printed paper delivered from the printer, then feeds the paper with the surface-printed toward the press roller 21, reverses it with the press roller 21, and re-feeds it toward the printing unit 16. Means 45 and the like.
As described above, the double-sided stencil printing apparatus 300 includes a single ink supply unit, a single plate cylinder 1 and a single press roller 21, and makes one rotation of the plate cylinder 1 as described later. Therefore, a one-plate cylinder 1-pressing means double-sided printing method capable of printing on both sides of the paper is adopted. The plate making unit 15, printing unit 16, discharge plate unit 17, paper feeding unit 30, paper discharge unit 19, image reading unit 18, refeeding unit 45 in the refeeding unit 48, moving guide 81, moving unit 87, The operation timing control means and the switching guide 46 are each configured as a device as will be described later.

The plate making unit 15 performs plate making on the master 8 and, as shown in FIG. 9, the first plate making image for surface printing along the rotation direction of the plate cylinder 1 (which is also the paper transport direction X and the master transport direction X1). Master plate 8X for double-sided printing (hereinafter referred to as “backside plate-making image 8B”) and 8A (hereinafter referred to as “front-side plate-making image 8A”) and second plate-making image 8B for backside printing (hereinafter referred to as “backside plate-making image 8B”). (In other words, “partitioned plate-making master 8X”), or as shown in FIG. The plate making master 8Y having the plate making image 8YA (hereinafter referred to as “single-side plate making image 8YA”) is provided. The front plate-making image 8A is formed at a position corresponding to the surface region 1A shown in FIG. 1 when the divided plate-making master 8X is wound on the outer peripheral surface of the plate cylinder 1, and the back plate-making image 8B is the same as the back surface region 1B. And corresponding positions.
In FIG. 1 and FIG. 9 and the like, the master-making master 8Y is indicated with parentheses to distinguish it from the divided master-making master 8X. In FIG. 9, the area range of the single-side plate-making image 8YA formed on the plate-making master 8Y is indicated by a two-dot chain line, and the boundary line of the same area range in the master transport direction X1 is the solid line of the front-side plate-making image 8A and the back-side plate-making image 8B. Although the area range is illustrated as being slightly larger, the area range of the single-side plate-making image 8YA is an intermediate unprinted blank area located between the front-side plate-making image 8A, the back-side plate-making image 8B, and these. This is the entire range including the plate making area 8C.

  The plate making unit 15 includes a master support member 8c that supports the master 8 so that the master 8 can be fed out in the master transport direction X1, a thermal head 11 that heats the master 8 that has been fed out according to image information, and the master 8 on the thermal head 11. A platen roller 9 that conveys the master 8 while rotating the master 8 downstream in the master conveying direction X1 while pressing, and a master 8 that has been conveyed by the platen roller 9 while applying appropriate tension further downstream in the master conveying direction X1. A pair of transport rollers 13 to be transported, a cutter 12 disposed between the platen roller 9 and the pair of transport rollers 13 for cutting the master 8 that has been subjected to plate making or the master 8 that has not yet been made, and a platen roller 9 and A master guide plate 14 that guides the leading end of the master 8 conveyed by the conveying roller pair 13 to the clamper 7 that is expanded on the plate cylinder 1. Comprising the door.

The master 8 is wound around a roll core 8b to form a master roll 8a. In the master roll 8a, the roll cores 8b on both ends are rotatably supported by the master support member 8c in a counterclockwise direction, and are detachable from the master support member 8c. The master support members 8c on both ends are attached and fixed to plate making side plate pairs (not shown) disposed on the left and right sides of the plate making portion 15 along the master transport direction X1. Therefore, the master 8 is supported by the master support member 8c so that it can be fed out from the master roll 8a in the master transport direction X1.
The master 8 has a laminated structure in which, for example, a thermoplastic resin film having a thickness of 1 to 5 μm and a porous support made of synthetic fiber or the like are bonded together. The master is not limited to this. For example, a master made by bonding a porous support and a thermoplastic resin film made of Japanese paper fiber or a mixture of Japanese paper fiber and synthetic fiber, or a so-called substantially thermoplastic resin film. A master or the like consisting only of the above is also used.

The thermal head 11 extends in parallel to the platen roller shaft of the platen roller 9 and the near side and the back side of the paper surface of FIG. 1, and is provided by a contact / separation mechanism including a cam and a spring member (not shown). The platen roller 9 can be contacted and separated via the master 8. The thermal head 11 is urged by the spring member so as to contact the platen roller 9. In the main scanning direction of the thermal head 11, a large number of heat generating elements (not shown) are disposed at portions that contact the platen roller 9 via the master 8. The thermal head 11 passes through an A / D conversion unit and an image signal processing unit, both not shown, and the heat generation based on a digital image signal processed and sent out by a plate making control device and a thermal head drive circuit (both not shown). By selectively heating the element, it has a well-known function as a plate making means for selectively heating and melting and perforating the master 8.
The platen roller 9 is formed integrally with the platen roller shaft. The platen roller 9 is rotatable clockwise because both ends of the platen roller shaft are rotatably supported by the plate making side plate pair. The platen roller 9 is connected to a master transport motor 10 via a rotation transmission member (not shown) such as a timing belt and a gear, and is thereby driven to rotate clockwise. The master transport motor 10 is composed of, for example, a stepping motor. As described above, when the platen roller 9 is driven to rotate clockwise by the master transport motor 10, the master 8 is pulled out from the master roll 8a.

The conveying roller pair 13 is provided with an appropriate pressing force by an urging means such as a spring and pressed against each other, and both end portions of each roller shaft are rotatably supported by the plate making side plate pair. Thus, they can rotate in opposite directions. The conveyance roller pair 13 is set to rotate at a circumferential speed (conveyance speed) slightly faster than the circumferential speed (conveyance speed) of the platen roller 9 by the rotation transmission member including the master conveyance motor 10. Appropriate front tension is applied to the master 8 while sliding between the two.
The cutter 12 is a known guillotine type that includes a fixed blade 12b and a movable blade 12a. The cutter 12 is not limited to the guillotine type, and may be a rotary blade moving type in which the movable blade moves while rotating in the master width direction orthogonal to the master transport direction X1.

The plate making unit 15 includes components that constitute plate feeding means capable of transporting and winding the master-made master 8 to the plate cylinder 1. As plate feeding means, a platen roller 9 of the plate making section 15, a conveying roller pair 13, a master guide plate 14, a clamper 7 of the plate cylinder 1 described later, an opening / closing device and a plate as an opening / closing means (not shown) for driving the clamper 7 to open and close. A main motor 20 that rotationally drives the body 1 is included.
In the plate making section 15 shown in FIG. 14, the control target drive means of the plate making section 15 including the thermal head 11 driven by a thermal head drive circuit (not shown) and the master transport motor 10 is collectively referred to as the plate making drive means 124. .

  The plate cylinder 1 has a two-layer structure of a porous and cylindrical support cylinder and a mesh screen (not shown) made of a resin or metal mesh wound around a plurality of layers so as to cover the outer periphery of the support cylinder. Consists of. The plate cylinder 1 is provided with a printable aperture 1a (hereinafter sometimes referred to as “image forming region”) in which a large number of ink-permeable apertures are formed, a clamper 7 and the like, and cannot be printed. A non-opening portion (hereinafter sometimes referred to as “non-image forming region”) is formed along the rotation direction of the plate cylinder 1 indicated by an arrow in FIG. The image forming area includes a first image area 1A (hereinafter referred to as “front surface area 1A”), an intermediate area 1C, and a second image area 1B (hereinafter referred to as “back surface area 1B”) in the plate cylinder 1 in FIG. ”) At least.

  The plate cylinder 1 is wound and fixed around an outer peripheral portion of an end plate flange (not shown), and is rotatably supported around a support shaft 5 that also serves as an ink pipe 5 described later. In terms of the embodiment, the size of the plate cylinder 1 is, for example, a size that can be printed on A3 size paper 36 at the maximum during single-sided printing to obtain an A3 size printed matter, that is, A3 size 1 The plate master 8 has a size capable of being wound, its outer diameter is 180 mm (the outer peripheral length of the plate cylinder 1 is about 565 mm), and its width direction (rotation center axis direction) is 350 mm. Is set.

  The plate cylinder 1 is connected to a main motor 20 as a plate cylinder driving unit via a drive transmission unit such as a gear or a belt (not shown). It is rotationally driven (clockwise). The output shaft of the main motor 20 is provided with an optical rotary encoder (not shown) and a plate cylinder sensor (not shown) that sandwiches the optical rotary encoder and generates a pulse by the cooperative action of the rotary encoder. Yes. The plate cylinder sensor includes a transmissive optical sensor (hereinafter simply referred to as a “transmissive optical sensor”) having a light emitting unit and a light receiving unit, and controls the rotational speed (printing speed) and rotational position of the plate cylinder 1. It is used for indexing etc.

Inside the plate cylinder 1 is rotatably supported by a side plate (not shown), and the rotational driving force of the main motor 20 is transmitted by a drive transmission means such as a gear (not shown) so as to be synchronized with the rotation of the plate cylinder 1. An ink roller 2 that is driven to rotate in the direction of the middle arrow (clockwise) and contacts the inner peripheral surface of the plate cylinder 1 to supply ink, and an ink roller 2 that is arranged in parallel with the ink roller 2 with a slight gap therebetween. A doctor roller 3 for forming an ink reservoir 4 having a wedge-shaped cross section and an ink pipe 5 for supplying ink to the ink reservoir 4 are disposed between the two. The ink roller 2, the doctor roller 3, and the ink pipe 5 constitute a single ink supply means for supplying ink to the divided master-making master 8X and the master-making master 8Y on the plate cylinder 1.
The ink in the ink reservoir 4 is sucked by an ink pump (not shown) from an ink pack (not shown) provided outside the plate cylinder 1, supplied from the supply hole of the ink pipe 5, and kneaded. The ink in the ink reservoir 4 is supplied as a thin film on the outer peripheral surface of the ink roller 2 while being measured by the doctor roller 3, and the outer peripheral surface of the ink roller 2 is in contact with the peripheral surface of the support cylinder in the plate cylinder 1. Is supplied to the opening 1a portion of the plate cylinder 1.

  A portion of the plate cylinder 1 on the outer peripheral surface of the non-opening portion includes a ferromagnetic stage 6 provided along one bus bar of the plate cylinder 1 and clampers provided on both side ends of the stage 6. A clamper 7 having a rubber magnet that is rotatably attached to the shaft and can be opened and closed with respect to the flat surface of the stage 6 is provided. The clamper 7 is opened and closed at a predetermined position by an opening / closing device (not shown) provided on the main body frame side. The plate cylinder 1 is stopped in a state in which the clamper 7 is positioned almost directly as shown in FIG. The plate cylinder 1 is configured as a plate cylinder unit integrally formed with an ink pack mounting table (not shown) on which the ink pack is detachably mounted, the ink pump, and the like. The ink pipe 5 is detachable from the main body frame in the axial direction.

In FIG. 1, on the end plate flange of the plate cylinder 1 on the back side of the paper surface and on the main body frame side near the end plate flange, as shown in FIG. Components for giving start / trigger information to the sheet feeding motor 37 and the registration motor 41 shown in FIGS. 1 and 11 are arranged. That is, on the outer wall of the end plate flange on the back side of the plate cylinder 1, the sheet feeding start light shielding plate 121 and the resist start light shielding plate 122 are spaced apart from each other on the same circumference of the plate cylinder 1. Each is attached to a predetermined position.
On the other hand, on the main body frame side in the vicinity of the light shielding plates 121 and 122, these are opposed to the same circumference of the plate cylinder 1 to which the paper feeding start light shielding plate 121 and the resist start light shielding plate 122 are attached. A sheet feeding registration sensor 120 is attached in a sandwiching manner. The paper feed registration sensor 120 is a transmissive optical sensor.

In the present embodiment, the home position (initial position) of the plate cylinder 1 is the tip of the divided plate-making master 8X or the plate-making master 8Y conveyed from the plate-making unit 15 with the clamper 7 positioned almost directly above. It is set to the same position as the plate feeding standby position, which is the position for receiving and holding. A light shielding plate for home position (not shown) for detecting the home position of the plate cylinder 1 is attached to a predetermined position of the outer wall of the end plate flange on the back side of the plate cylinder 1. A home position sensor (not shown) is attached to the main body frame side in the vicinity of the home position light shielding plate so as to face the home position light shielding plate of the plate cylinder 1 and sandwich it. The home position sensor is a transmissive optical sensor.
In FIG. 14, the plate cylinder sensor, the paper feed registration sensor 120, and the home position sensor are collectively referred to as a plate cylinder position detection sensor 29 as a plate cylinder position detection unit that detects the rotational position of the plate cylinder 1.

A single press roller 21 is disposed near the lower part of the outer peripheral surface of the plate cylinder 1 facing the ink roller 2. The press roller 21 is configured by integrally fixing an elastic body to the press roller shaft 21 a and is provided to extend in the axial direction of the plate cylinder 1. The press roller 21 is formed so that its lateral width is substantially the same as the lateral width of the plate cylinder 1. As shown in FIGS. 2 to 4, the press roller 21 has a pair of printing arms 22 as pressing means support members disposed on the front side and the back side of the sheet via both ends of the press roller shaft 21 a. (The front side of the paper is omitted) and is supported rotatably.
Note that the size and size of the plate cylinder 1 is greatly exaggerated as compared with that of the press roller 21, and in the embodiment, as disclosed in, for example, Japanese Unexamined Patent Application Publication No. 2003-200355, Needless to say, the ratio of the diameter of the press roller to the diameter of the plate cylinder is preferably 1: 2 or 1: 3 in order to easily make the peripheral speed the same as that of the plate cylinder. Of course, if the above-mentioned advantage is not desired, the circumferential length of the peripheral surface of the press roller 21 is simply larger than the circumferential length of the front surface region 1A or the back surface region 1B on the outer peripheral surface of the plate cylinder 1. Longer ones may be used.

  Each printing pressure arm 22 is arranged with substantially the same shape and the same phase on the front side and the back side of the drawing. Each printing pressure arm 22 is integrated with an arm shaft 22a attached and fixed to a portion near the bent portion and a connection reinforcing member (not shown). A notch 22b that selectively engages with a locking claw 60a of a locking member 60 described later is formed at the lower end of the printing pressure arm 22 shown in the figure. The arm shaft 22a is rotatable at a predetermined angle via a bearing (not shown) between a pair of housing side plates (not shown) fixed on the main body frame side (see the housing side plate pairs 130a and 130b in FIG. 7). It is supported by.

The press roller 21 is formed 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 a film having a fine uneven surface treatment, for example, For example, glass beads as glassy 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. Not only glassy fine particles but also ceramic fine particles may be used. As a result, when the outer peripheral surface of the plate cylinder 1 or the divided master-making master 8X or the master-making master 8Y on the plate cylinder 1 comes into contact, or as described later with reference to FIG. 4, the printed image of the surface-printed paper 36a. Swelling and ink stain due to contact with the ink on the surface side are minimized.
The press roller 21 is not applied to the divided plate-making master 8X or the plate-making master 8Y on the plate cylinder 1 via the printing pressure range varying means 28, the locking means 64 and the printing pressure arms 22 shown in FIGS. The printing position shown in FIGS. 3 and 4 that presses the printing paper 36 or the surface-printed paper 36a and the non-printing position including the initial position shown in FIGS. 1 and 2 away from the printing position are configured to be displaceable. Has been. As described above, the pair of printing arms 22 as the pressing means support members support the press roller 21 as the pressing means so as to be rotatable, and make the press roller 21 contactable / separable with respect to the plate cylinder 1. It is configured to be displaceable. The printing pressure range varying means 28 may also be called a press roller contacting / separating mechanism as pressing means contacting / separating means.

In FIG. 2, reference numeral 54 denotes a press roller rotation driving unit as a pressing unit driving unit that rotationally drives the press roller 21. The press roller rotation drive means 54 is a press roller drive as a drive means for driving the press roller 21 to rotate in the direction opposite to the rotation direction of the plate cylinder 1 (counterclockwise) at substantially the same peripheral speed as that of the plate cylinder 1. The motor 55 and the driving force transmitting means for transmitting the rotational driving force of the press roller driving motor 55 to the press roller 21 are mainly configured. The press roller drive motor 55 is attached and fixed to the outer wall of the printing pressure arm 22 on the back side in FIG.
As shown in FIG. 2, the drive force transmission means includes a toothed drive pulley 56 fixed to the output shaft 55a of the press roller drive motor 55, and a press roller protruding further to the back side of the paper surface of the printing pressure arm 22. A toothed driven pulley 57 fixed to the shaft 21a and a toothed endless belt 58 stretched between the driving pulley 56 and the driven pulley 57 are provided.

  The press roller 21 is a press roller driving motor in accordance with the timing when the unprinted paper 36, the front surface printed paper 36a, or the single-side printed paper 36c is pressed against the divided master making master 8X or the master making master 8Y on the plate cylinder 1. 55 is rotationally driven. The operation of the press roller drive motor 55 is controlled by the control device 100 shown in FIG. Control of the rotational speed of the press roller drive motor 55 via the driving force transmission means is performed so that the peripheral speed of the press roller 21 is substantially the same as the peripheral speed of the plate cylinder 1 as described above. According to the example of the present embodiment, since the press roller 21 is rotationally driven by the press roller drive motor 55 at a circumferential speed that is substantially the same as the circumferential speed of the plate cylinder 1, it is possible to obtain a good printed matter with no print image positional deviation. it can.

As shown in FIGS. 1 to 6, in addition to the press roller 21 constituting the refeed means 45, the refeeding conveyance device 104 and the refeed resist resist contact shown only in FIG. A separating means 70, a stopper member 53, a roller guide plate 50, and the like are disposed.
The refeed unit 45 temporarily holds the surface-printed paper 36 a on which the printed image is formed by the printing unit 16 and conveys the paper 36 a toward the press roller 21 via the stopper member 53. A re-feed transport device 104 as a re-feed transport device that can be stopped and started, and the leading edge of the front-side printed paper 36a transported by the re-feed transport device 104 Although it is “end”, since it is “front end” or “front end” in the transport direction of the surface-printed paper 36a, it is temporarily stopped before positioning to the press roller 21). A stop member 53 as a refeed stop means for performing the stop and the stop state of the front end of the front surface printed paper 36a temporarily stopped by the stopper member 53 are released at a predetermined timing, and the front surface mark Refeed resist as a refeed resist means that is displaceable between a contact position where the leading edge of the used paper 36a contacts (contacts) the press roller 21 and a non-contact position spaced apart from the contact position A roller 51, a paper re-feeding resist contacting / separating means 70 for displacing the paper re-feeding registration roller 51 between a contact position and a non-contact position, and a right side of the press roller 21 in proximity to the outer peripheral surface of the press roller 21. A roller guide plate 50 as a paper refeeding guide means that is provided and guides the surface-printed paper 36 a that is in contact with the outer peripheral surface of the press roller 21 by the refeeding registration roller 51 to the nip portion 16 a formed in the printing unit 16. And is composed mainly of.

  As shown in FIGS. 1 to 6, the re-feed conveyance device 104 is disposed below the reciprocating path of the moving guide 81 and in the vicinity of the left side of the re-feed registration roller 51. As shown in detail in FIGS. 2 to 6, the refeed conveyance device 104 is integrally provided on the drive shaft 107 a and a refeed housing 110 that rotatably supports the drive shaft 107 a and the driven shaft 106 a. As a driven roller provided integrally with a driven shaft 106a disposed upstream of the drive shaft 107a and in the vicinity of the paper re-feeding registration roller 51 at the upstream side of the drive shaft 107a and in the vicinity of the re-feeding registration roller 51. Air as an endless belt that holds and conveys the surface-printed paper 36a that is wound and stretched between the front conveyance roller 106, the rear conveyance roller 107, and the front conveyance roller 106, and delivered from the movement guide 81. A plurality of conveying belts 108 formed with a plurality of suction holes 108a are connected to the driving shaft 107a via a driving force transmitting means such as a gear or a belt. The belt drive motor 105 serving as a belt driving means for rotating the conveyor belt 108 via the rotational drive 7 and the surface-printed paper 36a delivered from the movement guide 81 are conveyed by sucking air from a large number of holes 108a. A suction fan 109 for adsorbing and holding on the upper surface side of the belt 108 is mainly configured. It should be noted that although the interval between the re-feeding registration roller 51 and the conveyance roller front 106 is illustrated with a considerable distance for the sake of simplicity of the drawing, it is noted that they are arranged close to each other.

The re-feeding casing 110 is formed so that its upper surface is open and its width is slightly smaller than the interval between the printing pressure arms 22, and has a substantially U-shaped side section. The bottom wall of the refeed housing 110 is formed with a number of holes or slits (not shown) for letting the air flow from the suction fan 109 escape downward. The re-feeding casing 110 has bearings (not shown) on both the upstream and downstream sides in the sheet conveying direction, and these bearings rotatably support the drive shaft 107a and the driven shaft 106a, respectively. Yes. Both ends of the drive shaft 107a penetrate both side surfaces of the refeed housing 110, and both ends of the penetrated drive shaft 107a can be rotated by a bearing member (not shown) provided on the main body frame. It is supported.
A drive gear (not shown) is attached to one end of the drive shaft 107a (the back side of the drawing in FIGS. 2 to 5), and the drive shaft 107a is rotated by a belt drive motor 105 connected via the drive gear. Driven. The conveyor belt 108 is intermittently rotated clockwise at a specific timing according to the type of paper as will be described later by the operation of the belt drive motor 105 based on the command signal from the control device 100 shown in FIG. . The belt drive motor 105 is formed of a stepping motor, for example, and is fixed to the main body frame side. The driven shaft 106 a is configured such that both ends thereof do not penetrate both side surfaces of the refeed housing 110.
Pins 111 are respectively protruded and fixed to the outer walls on both sides of the upstream end portion in the paper transport direction X in the paper refeed housing 110, and each pin 111 is formed on each printing pressure arm 22. The loose holes are loosely fitted to the respective escape holes. As a result, the refeeding housing 110 is driven by the drive shaft 107a as the printing pressure arm 22 swings when the press roller 21 is brought into contact with and separated from the plate cylinder 1 by the printing pressure range varying means 28 described later. The paper refeeding / conveying device 104 on the side where the pin 111 is arranged can be swung.

The conveyance roller rear 107 and the conveyance roller front 106 are divided into skewers, are formed of, for example, a toothed roller, and are formed of a high friction material. Incidentally, it is desirable to form the post-conveyance roller 107 and the pre-conveyance roller 106 with a high friction material having oil resistance (ink corrosion resistance) such as nitrile rubber (NBR) or an appropriate resin. The conveyor belt 108 is formed of, for example, a toothed belt, and a plurality of belts are wound and stretched between a conveyor roller rear 107 and a conveyor roller front 106 which are divided into skewers. Incidentally, the conveyor belt 108 is desirably formed of, for example, nitrile rubber (NBR) which is an elastic body having oil resistance (ink corrosion resistance).
The suction fan 109 is rotated by the suction fan 109 so that the surface-printed paper 36 a delivered from the moving guide 81 is attracted to the upper surface side of the transport belt 108 by sucking air from the numerous holes 108 a of the transport belt 108. A fan drive motor is incorporated as a fan drive means for driving. Hereinafter, the fan drive motor is simply referred to as “suction fan 109”.

The stopper member 53 temporarily stops the front end of the front surface printed paper 36a at a position where it can be delivered to the press roller 21, and also has a function of positioning the front end of the front surface printed paper 36a and correcting skew. The stopper member 53 is made of, for example, a sheet metal or an appropriate resin, has a substantially L-shaped cross section, and includes a stopper surface 53a for abutting and positioning the front end of the surface-printed paper 36a. The stopper member 53 has cutout openings at a plurality of locations so as not to come into contact with each other when the plurality of refeeding registration rollers 51 are in contact with the press roller 21. The left end side of the stopper member 53 in the drawing is fixed to the refeed housing 110, and thereby the stopper member 53 is rocked and displaced together with the refeed conveyance device 104 and the press roller 21. Needless to say, the stopper member 53 can be provided separately from the paper refeeding / conveying device 104.
Note that the re-feed conveyance unit and the re-feed stop unit are not limited to the re-feed conveyance device 104 and the stopper member 53 of the present embodiment, and are illustrated in, for example, Japanese Patent Application Laid-Open Nos. 2003-266906 and 2004-224479. As shown in FIGS. 1 to 4 and the like, it may be a refeed positioning member (24) integrally attached to the refeed transport unit (25) and the auxiliary tray (8).
As shown in FIGS. 2 to 4 and 6, at the upstream end portion of the stopper member 53 in the paper conveyance direction X, the front surface printed paper for detecting that the front end of the front surface printed paper 36 a is close to the stopper member 53. A re-feed sensor 52 as a detecting means is provided. The re-feed sensor 52 includes a reflection-type optical sensor, and includes a front end (front right side of the front surface printed paper 36a illustrated in FIG. 4) and a rear end (left end of the front surface printed paper 36a illustrated in FIG. 4). ).

As shown in FIG. 4, the re-feeding resist contacting / separating means 70 mainly includes a support shaft 72, a pair of swing arms 71, a solenoid 73, and a tension spring 75. The re-feeding registration roller 51 has a roller shape, is a high friction material, and is an elastic body having oil resistance (ink corrosion resistance), for example, nitrile rubber (NBR), and is divided into skewered shafts 51a. And is formed integrally. The re-feeding registration roller 51 is normally held in a state where it occupies a non-contact position on the lower side of the press roller 21 and the stopper member 53, and each swinging portion in which both end portions of the shaft 51a have a substantially square shape. The arm 71 is rotatably attached to one end. Each swing arm 71 has a bent portion fixed to a support shaft 72 that is rotatably supported between the printing pressure arms 22. As a result, when the re-feeding registration roller 51 occupies the contact position, it receives the rotational force of the press roller 21 and rotates in the direction opposite to the rotation direction (counterclockwise) of the press roller 21 (clockwise).
In the figure, a plunger 74 of a solenoid 73 is attached to the other end of the swing arm 71 on the back side of the drawing through a pin. The solenoid 73 is a pull type, and is attached and fixed to one printing pressure arm 22 via a bracket which is a non-moving member (not shown). Further, the other end of the swing arm 71 is fixed to one printing pressure arm 22 and is urged to always urge the re-feeding registration roller 51 in the direction of occupying the non-contact position around the support shaft 72. The other end of the spring 75 is attached. The solenoid 73 has a function as a refeed resist driving unit that displaces the refeed resist roller 51 so as to occupy the contact position at a predetermined timing.
As described above, when the solenoid 73 is operated against the urging force of the tension spring 75 (ON operation), the outer sheet of the re-feeding registration roller 51 is pressed against the outer periphery of the press roller 13 with a predetermined pressing force. By contacting the surface and occupying the contact position, the surface-printed paper 36a is brought into contact with the outer peripheral surface of the press roller 21 for a predetermined time, and receives the rotational force of the press roller 21 in the clockwise direction opposite to the press roller 21. When the surface-printed paper 36a is assisted while being rotated and the operation of the solenoid 73 is released (OFF operation), the outer peripheral surface of the press roller 13 is separated from the outer peripheral surface by the urging force of the tension spring 75. Occupies a non-contact position.

The roller guide plate 50 has a function of guiding the surface-printed paper 36 a conveyed by the rotational force of the press roller 21 toward the plate cylinder 1 by abutting the outer peripheral surface of the press roller 21. The roller guide plate 50 has a curved partial cylindrical shape centered on the press roller shaft 21a in order to guide the surface-printed paper 36a along the outer peripheral surface of the press roller 21. The roller guide plate 50 and the outer peripheral surface of the press roller 21 have a predetermined shape. Are fixed between the printing pressure arms 22. The guide surface side of the surface-printed paper 36a on the roller guide plate 50 has a low coefficient of friction with respect to the surface-printed paper 36a and a smooth coating film having ink repellency and oil resistance such as polytetrafluoroethylene resin. It is coated.
In FIG. 14, the control target drive means of the refeed means 45 includes a press roller drive motor 55, a solenoid 73, a belt drive motor 105, a suction fan 109, and the like. Various detection means of the paper refeed means 45 include a paper refeed sensor 52 and the like.

Next, the configuration around the printing pressure range varying means 28 that determines the printing pressure range of the press roller 21 will be briefly described. In the present embodiment, as shown in FIGS. 1 and 9, a first printing pressure range pattern that applies printing pressure only to the surface region 1A corresponding to the surface plate-making image 8A in the divided plate-making master 8X on the plate cylinder 1 is used. And a printing pressure range pattern as a second printing pressure range pattern that applies printing pressure only to the back surface area 1B corresponding to the back plate making image 8B in the divided plate-making master 8X on the plate cylinder 1. II and a printing pressure range as a third printing pressure range pattern that applies a printing pressure from the front surface area 1A to the back surface area 1B corresponding to the single-side plate-making image 8YA in the plate-making master 8Y on the plate cylinder 1. One of at least three printing pressure range patterns with the pattern III can be selectively switched. A part of the mechanism relating to the printing pressure range varying means 28 for selectively switching one of these three printing pressure range patterns is shown in FIGS. The printing pressure range varying means 28 also has a configuration / function for displacing the press roller 21 between the printing position and the non-printing position.
The printing pressure range variable means 28 includes a multi-stage cam (43), a step cam (49), and a stepping motor that rotationally drives the step cam (49) shown in FIGS. (52) etc. It is the structure similar to the press roller contacting / separating mechanism (55). Incidentally, in FIG. 2 and FIG. 3, the printing pressure range varying means 28 is composed of components such as a multi-stage cam (43), a step cam (49), and a stepping motor (52) that constitute the press roller contact / separation mechanism (55). A part thereof is represented by a sign obtained by adding a numerical value “200” to the sign of the above, and the arm shaft 22a, the printing pressure arm pair 22, the pair of cam followers 241, the pair of printing pressure springs 242, and the printing pressure cam shaft. 244, a pair of multistage cams 243, and the like. The stepping motor 252 is shown only in the printing pressure range varying means 28 shown in FIG. 14 and FIG. 15 described later.

  As shown in FIGS. 2 and 3, each of the constituent elements constituting the printing pressure range varying means 28 basically applies a uniform pressing force of the press roller 21 to the outer peripheral surface of the plate cylinder 1. Since the press roller 21 is disposed on the front side and the back side of the paper as viewed from FIG. 1 (the front side of the paper is omitted), the components on the back side of the paper will be described as a representative. Therefore, the description on the front side of the sheet is omitted. If the printing pressure range variable means 28 does not need the advantages as described above, the constituent elements of the printing pressure range variable means 28 are, for example, the back of the paper surface of FIGS. Of course, it may be arranged only on the side.

As shown in FIGS. 2 and 3, a cam follower 241 pivots on the outer wall at the center of the printing pressure arm 22 facing the inside of the printing pressure arm 22 on which the press roller 21 is supported. Is held. The cam follower 241 is configured by a rolling bearing so that the cam follower 241 can come into contact with the multistage cam 243 with reduced frictional resistance.
One end of a printing spring 242 (tensile spring) that constantly urges the press roller 21 in a direction in which it presses against the outer peripheral surface of the plate cylinder 1 is locked to the other end of the printing pressure arm 22. The other end is locked to the housing side plate side. By this printing pressure spring 242, the other end side of the printing pressure arm 22 is swung and urged clockwise around the arm shaft 22 a, and the press roller 21 is urged in a direction in which it is pressed against the outer peripheral surface of the plate cylinder 1. ing. A notch 22b that can be engaged with the locking claw 60a of the locking member 60 is integrally formed at the other end of the printing pressure arm 22, and can be engaged with and disengaged from the locking member 60.
On the other hand, a printing pressure cam shaft 244, to which a pair of multi-stage cams 243 rotating in synchronization with the rotation of the plate cylinder 1 is fixed, is rotatably supported on the respective housing side plates near the respective cam followers 241. The multistage cam 243 is composed of, for example, a plate cam in which a small diameter portion (concave portion) and a large diameter portion (convex portion) are formed.

A belt pulley or gear (not shown) is fixed to the printing cam shaft 244, and is connected to the main motor 20 via a drive transmission means such as a belt or gear (not shown). The plate cylinder 1 rotates in synchronization with the rotation of the plate cylinder 1. The cam follower 241 is urged by the above-described printing pressure spring 242 so as to always come into contact with the multistage cam 243. Therefore, the cam driving means for rotationally driving the multistage cam 243 is mainly composed of the main motor 20.
Each multistage cam 243 has three cam plates 243A, 243B, and 243C, which are fixed to the printing cam shaft 244 at an appropriate interval. The cam plates 243A, 243B, and 243C are arranged in the order of the cam plate 243B, the cam plate 243A, and the cam plate 243C from the front side of the sheet of FIG. 2 and FIG. Each of the cam plates 243A, 243B, and 243C has a small-diameter portion (concave portion or base portion) that is a disc concentric with the cam shaft 244, and a large-diameter portion (convex portion) having the same protruding amount. The multistage cam 243 is a camshaft 244, that is, a drive gear (45) attached to the camshaft (44) shown in FIG. The rotational force from the plate cylinder driving means (121), that is, the main motor 20, is transmitted through the transmission gear (47) attached to the shaft (46), and is driven to rotate clockwise in FIG.

The press roller 21 has a non-printing position shown in FIG. 2 in which the peripheral surface is separated from the outer peripheral surface of the plate cylinder 1 when any one of the large diameter portions of the cam plates 243A, 243B, 243C contacts the cam follower 241. 3 and 4 in which the peripheral surface is pressed against the outer peripheral surface of the plate cylinder 1 by the urging force of the printing pressure spring 242 when the contact between any of the large diameter portions and the cam follower 241 is released. Occupy position. Each of the cam plates 243A, 243B, and 243C is configured so that the small diameter portion (base portion) and the cam follower 241 do not come into contact when the press roller 21 occupies the printing position.
The shape of the large diameter portion of each cam plate 243A, 243B, 243C is such that the contact range between the press roller 21 and the plate cylinder 1 is such that the surface region 1A, the intermediate region 1C and the back surface region 1B shown in FIG. The cam plate 243B has the same range as the surface region 1A (see the printing pressure range pattern I shown in FIG. 9) so that all the ranges are combined (see the printing pressure range pattern III shown in FIG. 9). The cam plate 243C is formed to have the same range as that of the back surface region 1B (see the printing pressure range pattern II shown in FIG. 9).

As shown in FIGS. 2 and 3, the locking means 64 is for holding the press roller 21 in the non-printing position shown in FIGS. The locking means 64 is mainly composed of a locking member 60, a support shaft 61, a solenoid 62, and a tension spring 63. The locking means 64 is disposed on the back side of the page.
The locking member 60 is swingably supported around a support shaft 61 planted on the housing side plate on the back side of the paper surface. One end of the locking member 60 is selected with the notch 22b of the printing pressure arm 22 described above. An engaging claw 60a that engages with each other is formed. One end of a tension spring 63 that urges the engaging claw 60 a in a direction to always engage with the notch 22 b of the printing pressure arm 22 is locked to the other end portion of the locking member 60. The other end of the tension spring 63 is locked to the housing side plate side on the back side of the drawing. Further, the plunger of the solenoid 62 fixed to the side of the other end portion of the locking member 60 facing the arrangement portion of the tension spring 63 via a bracket (not shown) as a stationary member on the housing side plate on the back side of the drawing. 62a is connected via a pin. The solenoid 62 uses a pull type.

As described above, when the solenoid 62 is energized and the solenoid 62 is turned on, the printing pressure range variable means 28 is operated, and the press roller 21 occupies the printing position through the operation described later. As a result, the press roller 21 continuously presses the paper 36 while rotating it on the divided master-making master 8X or the master-making master 8Y on the plate cylinder 1. When the energization of the solenoid 62 is interrupted and the solenoid 62 is turned off, the printing pressure range variable means 28 is deactivated, and the press roller 21 is separated from the printing position through the operation described later. 2 occupies the non-printing position (initial position).
The solenoid 62 is on / off controlled by a control device 100 described later. By the on / off switching control of the solenoid 62 by the control device 100, the state is selectively switched between a state in which the printing pressure arm 22 is held and a state in which the holding is released. As will be described later, the solenoid 62 is turned on when the cam follower 241 is in contact with the large diameter portion of the multistage cam 243 (see FIG. 2).

FIG. 9 is an expanded view of the printing pressure range of the press roller 21 for easy understanding. In FIG. 9, an area portion of the front plate-making image 8A and an area portion of the back-side plate-making image 8B are formed on the divided plate-making master 8X wound around the opening portion 1a on the plate cylinder 1 (not shown). In addition, there is an unfinished blank intermediate unfinished area 8C between them. Here, the leading side of the divided pre-printed master 8X, which is also referred to as the leading edge blank portion sandwiched and fixed by the clamper 7 of the plate cylinder 1 (not shown), is the left end side.
The printing pressure range pattern for normal printing including single-sided printing is as shown in III. That is, the printing pressure range pattern III is applied to one side of the prepressed master 8Y by applying a printing pressure from the area portion of the front plate making image 8A to the area portion of the back plate making image 8B through the intermediate non-plate making area 8C. The cam plate 243A is selected by operating the printing pressure range varying means 28 according to a command from the control device 100 shown in FIG. 14 so that the sheet 36 is continuously pressed against the plate-making image 8YA, and the cam plate 243A is selected. Is rotated so that the small diameter portion thereof faces the cam follower 241.

At the time of surface printing, the printing pressure range variable means 28 is operated by a command from the control device 100 so as to be printed corresponding to the area portion of the surface plate-making image 8A as shown in the printing pressure range pattern I. Thus, the cam plate 243B is selected, and the cam plate 243B is rotationally driven so that the small diameter portion of the cam plate 243B faces the cam follower 241 and then the printing pressure is released in the intermediate unmade region 8C.
At the time of printing on the back side, the printing pressure range pattern II is obtained, and the cam plate 243C is selected by the operation of the printing pressure range variable means 28 in response to a command from the control device 100, so that the region portion of the first front plate-making image 8A is selected. Then, in order to release the printing pressure, the cam plate 243C is rotationally driven so that the large diameter portion of the cam plate 243C faces the cam follower 241 and then the small diameter portion of the cam plate 243C faces the cam follower 241.

According to the present embodiment, since the printing pressure range variable means 28 is provided, the printing pressure on range is optimally set, and the printing pressure is turned on when there is no sheet and the press roller 21 It is possible to prevent a problem that the printed image is transferred to the outer peripheral surface and is stained with ink.
The printing pressure range variable means 28 includes the multistage cam (43), the step cam (49), and the press roller contact / separation mechanism (55) shown in FIGS. 2 and 4 of JP-A-2003-200355 as described above. For example, an emergency pressing release means (79) shown in FIGS. 1 to 4 of JP-A-2003-237030 may be applied.

  As shown in FIG. 1, the paper discharge unit 19 is provided so as to be close to the outer peripheral surface of the plate cylinder 1, and a peeling claw 170 that peels the single-side printed paper 36 c from the plate-making master 8 </ b> Y on the plate cylinder 1. A separation fan 171 for blowing air between the front end portion of the single-side printed paper 36c separated by the nail 170 and the plate cylinder 1 to assist the separation action by the separation nail 170, and separation by the separation nail 170 and the separation fan 171. The sheet discharge conveyance device 152 that conveys one of the printed single-sided printed paper 36c and the double-sided printed paper 36b while sucking, and the discharge tray 172 described above are mainly configured.

The peeling claw 170 is provided in the vicinity of the downstream side of the nip portion 16 a formed when the press roller 21 is pressed against the outer peripheral surface of the plate cylinder 1. The peeling claw 170 is placed on the plate cylinder 1 in the vicinity of the outer peripheral surface of the plate cylinder 1 by a peeling claw displacing means (not shown) provided with a cam, a spring, and the like that are rotated in synchronization with the rotation of the plate cylinder 1. A separation position for forcibly separating the single-sided printed paper 36c from the pre-printed master 8Y, and a non-peeling position for avoiding contact with the clamper 7 arrangement portion protruding from the outer peripheral surface of the plate cylinder 1 apart from the separation position It is configured to be freely displaceable between. The peeling fan 171 has a built-in fan drive motor that rotationally drives the peeling fan.
As shown in FIGS. 1 to 5, the paper discharge conveying device 152 is disposed below the peeling claw 170 and on the left side of the switching guide 46. The paper discharge roller rear 154 as a driving roller, a driven roller Are provided in front of the discharge roller 156, a discharge belt 158 which is an endless belt, a suction fan 159, and the like. A plurality of post-discharge rollers 154 have a roller shape and are attached to a drive shaft 154a rotatably supported by the pair of casing side plates at a predetermined interval. A plurality of front discharge rollers 156 are also provided on the driven shaft 156a rotatably supported by the casing side plate pair at equal intervals with the rear 154 of each discharge roller. A paper discharge belt 158 is stretched around each paper discharge roller 154 and each paper discharge roller front 156 corresponding thereto. A drive gear or drive pulley (not shown) is attached to the drive shaft 154a (for example, the back side of the paper in FIGS. 1 to 5), and a motor gear (not shown) that meshes with the drive gear or between the drive pulley and the pulley (not shown). It is connected to a paper discharge belt drive motor 153 via a driving force transmission means such as a stretched belt. Accordingly, the paper discharge belt 158 is rotationally driven by the paper discharge belt drive motor 153 in the direction of the arrow (counterclockwise) shown in FIG.

A suction fan 159 is disposed below the paper discharge belt 158. The suction fan 159 includes a fan drive motor that rotationally drives the suction fan. The paper discharge conveyance device 152 sucks either the single-side printed paper 36c or the double-side printed paper 36b on each paper discharge belt 158 by the suction force of the suction fan 159, and rotates the rear 154 after each paper discharge roller. 1 in the direction of the arrow.
In FIG. 14, the control target driving means of the paper discharge unit 19 including the fan drive motor of the separation fan 171, the paper discharge belt drive motor 153, and the fan drive motor of the suction fan 159 in the paper discharge unit 19 is collectively discharged. The driving means 127 is used.

As shown in FIGS. 1 to 5, the switching guide 46 includes a nip portion 16 a as a print image forming portion in the printing portion 16 formed by pressing the press roller 21 against the plate cylinder 1, and paper discharge conveyance. It is disposed on a paper conveyance path to and from the device 152. The switching guide 46 is made of a plate material having substantially the same width as that of the plate cylinder 1 and the press roller 21, and its base end portion (downstream end portion in the paper transport direction X) is supported by the casing side plate so as to be rotatable by a predetermined angle. The free end portion (the upstream end portion in the paper transport direction X) is swingable about the shaft 46a. The outer peripheral surface of the switching guide 46 may be smoothly coated with a film having ink repellency and oil resistance, such as polytetrafluoroethylene resin.
The switching guide 46 has a free end portion formed in an acute cross section when the solenoid 47 as the switching driving means shown in FIGS. 2 and 14 operates against the urging force of a tension spring as urging means (not shown). Are selectively positioned at a first displacement position indicated by a solid line and a second displacement position indicated by a two-dot chain line in FIG. The switching guide 46 is usually given a habit of swinging by the urging force of the tension spring at the first displacement position which is also the initial position shown in FIG. When the switching guide 46 occupies the first displacement position, the tip of the switching guide 46 comes close to the outer peripheral surface of the press roller 21 and does not interfere with the clamper 7 on the plate cylinder 1 and occupies the second displacement position. The tip of the plate cylinder 1 is placed close to the peripheral surface of the plate cylinder 1. The double-side printed paper 36b or the single-side printed paper 36c that has passed between the plate cylinder 1 and the press roller 21 is guided to the paper discharge unit 6 when the switching guide 46 occupies the first displacement position, The printed sheet 36a is delivered to the moving guide 81 while being guided by the switching guide 46 when the switching guide 46 occupies the second displacement position. The switching drive means for displacing the switching guide 46 between the first displacement position and the second displacement position is not limited to the combination of the solenoid 47 and the tension spring, and is driven by, for example, a stepping motor or a rotary solenoid. It may be.

  As shown in FIGS. 1 to 5, the movement guide 81 is disposed between the discharge conveyance device 152 and the switching guide 46 and the refeed conveyance device 104. As shown in FIGS. 3, 7 and 8, the moving guide 81 has a moving position P <b> 1 in which the leading end including the leading end of the front surface printed paper 36 a fed from the nip 16 a is a first position in the vicinity of the printing unit 16. 7 and FIG. 8, a sheet that opens the front end of the surface-printed sheet 36 a at the initial position P <b> 2 as the second position in the vicinity of the upstream side of the refeed unit 45 that is lower than the movement position P <b> 1. It has a function and configuration as a clamping means.

  The movement guide 81 is integrated with a clamping table 81f that clamps and places the front end of the surface-printed paper 36a, and a clamping table 81f that is downstream of the paper-printing direction Xa of the surface-printed paper 36a fed from the nip portion 16a. A pair of end fences 81d having a paper contact surface 81e that contacts the front end of the surface-printed paper 36a formed on the front and back sides of the paper surface of the clamping table 81f and integrated in the reciprocating direction. Four projections 81c as guided portions formed on the front surface, clamp claws 81b as clamping members that can be opened and closed with respect to a clamping base 81f that grips and clamps the front end portion of the surface-printed paper 36a, and clamp claws 81b A clamp shaft 81a that can be pivoted (rotated by a predetermined angle) for mounting and fixing the base end of the clamp, and a clamp shaft 81a for supporting the clamp shaft 81a so as to be rotatable by a predetermined angle. A pair of bearing brackets 81g shown only in FIG. 7 integrally attached to both side ends of the holding base 81f and the free end of the clamp claw 81b are pressed against the upper surface of the holding base 81f. It is mainly composed of a torsion coil spring (not shown) as an urging means, and a pair of upper and lower release levers 82 and a lower release lever 83 shown in FIG. 8 attached and fixed to the back side of the paper surface of the clamp shaft 81a. Yes.

The movement guide 81 is formed in a substantially L-shaped cross section by a clamping table 81f and an end fence 81d. The four protrusions 81c are loosely fitted in guide grooves 88 formed in the case side plate pairs 130a and 130b shown in FIG. The clamp claw 81b is inclined with an acute rising angle with respect to the paper traveling direction Xa (conveying direction) of the surface-printed paper 36a fed out from the nip portion 16a, and its base end is attached and fixed to the clamp shaft 81a. The free end is formed into an acute angle. In addition, the clamp claw 81b is made of metal or resin that extends and is fixed in the paper width direction Y of the clamp shaft 81a so as to clamp and grip the tip of the front surface printed paper 36a fed from the nip portion 16a. It consists of a thin plate-shaped member. A mounting portion 84 shown in FIG. 7 is integrally provided at a lower portion of the clamping table 81 f on the back side of the paper surface, and this mounting portion 84 is fixed to a timing belt 89 that constitutes the moving means 87.
The release lever 82 and the release lever lower 83 are formed of a plate-like member. Note that the protrusion 81c is not limited to being formed integrally with the holding base 81f, but may be formed of a roller that can roll on the inner wall of the guide groove 88 with little frictional resistance.

According to the movement guide 81 of this embodiment, the surface printing is provided by including the clamp claw 81b inclined with an acute rising angle with respect to the sheet traveling direction Xa of the surface printed sheet 36a fed from the nip portion 16a. When a load or the like is applied in the direction in which the surface-printed paper 36a is removed during conveyance of the used paper 36a, the moment of increasing the clamping force (pressing force), that is, the moment for rotating the clamp pawl 81b counterclockwise is generated. Therefore, the clamping force (pressing force) increases to prevent the sheet 36a from coming off, and the clamping force as a biasing force of a torsion coil spring (not shown) can be set small, and it is not necessary to make it firmly and inexpensively. It has the advantage of being configurable.
It should be noted that the portion of the moving guide 81 that contacts the surface-printed paper 36a is formed of a metal material having an antistatic action or subjected to an evaporation process or a plating process having an antistatic action. Is more preferable.

  As shown in FIG. 7, the moving means 87 is disposed outside the casing side plate 130b on the back side of the paper, and has a function and configuration for reciprocating the moving guide 81 between the moving position P1 and the initial position P2. Have The moving means 87 is an arcuate guide formed so as to be inclined downward to the left so as to be substantially the same as the transport drop path in the paper traveling direction Xa of the surface-printed paper 36a and penetrate the housing side plate pair 130a, 130b. A groove 88, a toothed drive pulley 90 rotatably supported with a shaft 90a on a housing side plate 130b in the vicinity of the downstream end in the paper traveling direction Xa of the surface-printed paper 36a in the guide groove 88, and a guide groove 88, a toothed driven pulley 91 having a shaft 91a rotatably supported by a housing side plate 130b in the vicinity of the upstream end in the paper traveling direction Xa of the front surface printed paper 36a, a driving pulley 90 and a driven pulley 91; A timing belt 89 that is stretched and stretched between the housing and the housing side plate 130b with a shaft (not shown) so as to contact and apply tension to the timing belt 89. A plurality of tension rollers 95 supported movably, a drive gear 92 attached and fixed to the shaft 90a of the drive pulley 90, and a forward and reverse rotation attached and fixed to the casing side plate 130b near the shaft 90a of the drive pulley 90 A drive motor 94 as a possible drive means and a motor gear 93 that is attached and fixed to the output shaft 94a of the drive motor 94 and meshes with the drive gear 92 are mainly configured.

The timing belt 89 is connected and fixed to the moving guide 81 via an attachment portion 84 formed integrally with the lower portion of the holding base 81 f of the moving guide 81. The drive motor 94 is composed of a stepping motor, for example. As described above, the driving motor 94 is the driving means of the moving means 87, the guide groove 88 is the guiding means of the moving means 87, and the timing belt 89, the driving pulley 90, the driven pulley 91, the driving gear 92, and the motor gear 93 are the driving motor 94. The driving force transmitting means for transmitting the driving force to the movement guide 81 is configured.
As shown in FIG. 3, FIG. 7, FIG. 8 and FIG. 8 in which the moving guide 81 clamps the front end of the surface-printed paper 36a through the driving force transmitting means by forward / reverse driving of the driving motor 94, as shown by the solid line in FIG. In the vicinity of the movement position P1 (first position) that is in the vicinity of the printing unit 16 and in the vicinity of the upstream side of the refeeding means 45 that is lower than the movement position P1 (near the upper part of the rear side of the conveyance roller 107 of the refeeding conveyance device 104). In order to selectively occupy the initial position or standby position (second position) indicated by a solid line in FIGS. 1 and 2 and a two-dot chain line in FIGS. Reciprocates. In the vicinity of the drive pulley 90, a home position sensor 85 is provided for detecting when the movement guide 81 occupies the second position, which is the home position P2 (initial position P2).

  As shown in FIG. 8, the release cam 98 and the torsion coil spring come into contact with the lower release lever 83 of the movement guide 81 when the movement guide 81 occupies the movement position P <b> 1 indicated by the solid line. The clamp claw 81b is swung clockwise (rotated by a predetermined angle) via the release lever lower 83 and the clamp shaft 81a against the urging force of the first position, and then once released, the movement guide 81 is moved from the movement position P1. When the movement starts toward the initial position P2 indicated by the chain line, the contact state with the lower release lever 83 is released, and the clamping claw 81b is swung counterclockwise by the biasing force of the torsion coil spring. Thus, it has a function as an operation timing control unit that operates so as to sandwich the leading end portion of the front surface printed paper 36a. As shown in FIG. 8, when the movement guide 81 occupies the initial position P2, the release pin 99 comes into contact with the release lever upper 82 of the movement guide 81, thereby resisting the biasing force of a torsion coil spring (not shown). It has a function as an operation timing control unit that operates to swing the clamp claw 81b clockwise via the release lever upper 82 and the clamp shaft 81a to open the front end of the surface-printed paper 36a.

  According to the present embodiment, the provision of the release cam 98 has the following advantages over the case where the release cam 98 is not provided. That is, for example, when the movement guide 81 occupies the movement position P1, the front end of the surface-printed paper 36a overcomes the urging force of a torsion coil spring (not shown) by the conveying force applied by the nip portion 16a, and the clamp pawl 81b is rotated clockwise. If the release cam 98 is removed so as to be inserted into the open portion (open portion between the tip of the clamp claw 81b and the upper surface of the clamping base 81f) by swinging, even if the twist Even if the biasing force of the coil spring is set according to a sheet with low stiffness, it is assumed that the leading end of the sheet is deformed or the sheet clamping force becomes unstable. On the other hand, according to the present embodiment, when the movement guide 81 occupies the movement position P1, the conveying force applied to the front end of the surface-printed paper 36a by the nip portion 16a by the action of the release cam 98 described above. Is smoothly inserted into the open portion (the open portion between the tip of the clamp claw 81b and the upper surface of the clamping table 81f), so that the surface-printed paper 36a is not affected by the strength of the paper. Can be securely clamped and clamped between the tip of the clamp claw 81b and the upper surface of the clamping table 81f, so that the surface-printed paper 36a can be kept in a stable state without meandering or skewing. It has the advantage that it can be transported well, and the printed image can be prevented from tilting during printing on the back side, and the resist from deteriorating due to tilting, etc. That. In addition, the opening time when the front end of the front-side printed paper 36a is clamped can be set to a certain extent by devising and adjusting the shape of the release cam. This can be performed without resistance, and the front-end printed sheet 36a can be favorably clamped at the front end.

  By the action and action of the release pin 99, when the movement guide 81 occupies the initial position P2, the front end portion of the surface-printed paper 36a held between the front end of the clamp claw 81b and the upper surface of the holding base 81f is released. The front surface printed paper 36a falls from the leading edge of the paper 36a onto the transport belt 108 of the refeed transport device 104, and is temporarily sucked and held on the transport belt 108 by the suction force of the suction fan 109 operating at this time. After that, it is conveyed by the rotational drive of the conveyor belt 108. Needless to say, the length of the transport belt 108 and the initial position P2 of the moving guide 81 are set to have optimum lengths depending on the length of the paper 36 used for duplex printing in the paper transport direction X.

The plate removal unit 17 includes an upper plate removal member 160, a lower plate removal member 161, a plate removal box 162, a compression plate 163, and the like. The upper plate removal member 160 includes a driving roller 164, a driven roller 165, an endless belt 166, and the like. The drive roller 164 is driven to rotate clockwise in FIG. 1 by a plate discharge driving means 126 (see FIG. 14) including a plate discharge motor (not shown), so that the endless belt 166 moves in the arrow direction in FIG. The lower plate removal member 161 includes a driving roller 167, a driven roller 168, an endless belt 169, and the like. The driving roller 167 is driven to rotate clockwise in FIG. 1 by transmitting the driving force of the plate discharging motor that rotationally drives the driving roller 164 by a driving force transmitting means (not shown) such as a gear or a belt. The endless belt 169 moves in the direction of the arrow in FIG. Further, the lower plate discharging member 161 is movably provided by a moving unit (not shown) included in the plate discharging driving unit 126, and an endless belt 169 positioned on the outer peripheral surface of the driven roller 168 and the position shown in the figure is the plate cylinder 1. And a position that abuts on the outer peripheral surface.
The plate removal box 162 stores a used master therein and is detachably attached to the main body frame 130. The compression plate 163 is supported by the main body frame 130 so as to be movable up and down so that the used master carried by the upper plate discharging member 160 and the lower plate discharging member 161 is pushed into the plate discharging box 162. It is moved up and down by lifting means (not shown) including the lifting motor included.
In FIG. 14, the discharge target drive means 126 is collectively referred to as the control target drive means of the discharge plate section 17 including the discharge motor, the moving means, and the lifting motor of the discharge section 17.

As shown in FIGS. 1, 10, and 11, the paper feed unit 30 comes into contact with the paper feed tray 35 that can stack and lift up the paper 36 so that it can be lifted and the paper 36 on the paper feed tray 35. The sheet feeding roller 33 and the separating member 34 as sheet feeding means for separating and transporting the sheet 36 one by one toward the nip portion of the pair of registration rollers 31a and 31b (hereinafter referred to as “registration roller pair 31”). A sheet size detection sensor 117 serving as a sheet size detection means for detecting the sheet size of the sheet 36, and a resist for feeding the sheet 36 at a later-described timing between the outer peripheral surface of the plate cylinder 1 and the press roller 21. And a registration roller pair 31 as a means.
On the paper feed path between the registration roller pair 31, the paper feed roller 33, and the separation member 34, a paper thickness sensor 79 is disposed as a paper type detection unit that detects the thickness of the paper 36. Although the paper thickness sensor 79 has been described in the present embodiment for the sake of convenience, the paper thickness sensor 79 is used in a modified example described later, and will be described below as not being provided in the present embodiment.

The paper feed tray 35 is provided with a drive device (not shown) including a paper feed tray lifting / lowering motor (not shown) as a lifting / lowering means (not shown) for moving the paper feeding tray 35 up and down. A state in which the upper layer contacts the paper feed roller 33 with a predetermined pressing force (a pressing force capable of transporting the paper 36), that is, a state in which the paper 36 contacts with a pressing force within a range in which the paper 36 can be transported in conjunction with increase / decrease of the paper 36. Is moved up and down while holding. The paper feed tray 35 has a structure in which many paper types and paper sizes can be used, and the paper stacking capacity thereof is, for example, a paper size A3 (horizontal placement: the user stands in front of the paper in FIG. And a structure suitable for a stencil printing apparatus capable of stacking 500 sheets or more of paper 36 of paper size A4.
In the paper feed tray 35, a pair of side fences (not shown) for positioning and aligning both side edges of the paper 36 according to the paper size is disposed so as to be movable in the paper width direction orthogonal to the paper transport direction X.
In the vicinity of the lower portion of the paper feed tray 35, paper length size detection sensors 117a, 117b, and 117c (both are made of a reflective optical sensor) for detecting the length of the fed paper 36 and the fed paper 36 In the figure, a paper width size detection sensor (not shown) that detects the paper width on the front side and the back side of the paper surface (for example, a transmissive optical sensor that detects the paper width in conjunction with the movement of the pair of side fences in the paper width direction) Are provided). The paper length size detection sensors 117a, 117b, and 117c and the paper width size detection sensor detect the size of the fed paper 36. Hereinafter, these are collectively referred to as the paper size detection sensor 117.

As shown in FIGS. 1 and 11, the paper feed roller 33 is formed integrally with the paper feed roller shaft 33a, and one end portion of the paper feed roller shaft 33a is rotatably supported by the casing side plate. Yes. The surface of the paper feed roller 33 is formed of at least a high friction resistance member such as rubber. A toothed paper feed roller pulley 39 is attached to one end of the paper feed roller shaft 33a. Between the paper feed roller shaft 33a and the paper feed roller pulley 39, a one-way clutch (not shown) for rotating the paper feed roller 33 so as to transport the paper 36 only in the paper transport direction X is disposed. Yes. The separation member 34 has a member called a separation pad that is made of rubber or resin having a high friction coefficient with respect to the paper 36 and that can contact the paper feed roller 33. This separation pad is urged in a direction to be pressed against the paper feed roller 33 by a compression spring (not shown) as urging means.
Below the paper feed roller pulley 39, a paper feed motor 37 as a paper feed driving means for rotationally driving the paper feed roller 33 is fixed to the casing side plate. The paper feed motor 37 is composed of, for example, a stepping motor, and a toothed paper feed motor pulley 38 is fixed to the output shaft thereof. A toothed paper feed motor belt 40 is stretched between the paper feed roller pulley 39 and the paper feed motor pulley 38. As a result, the paper feed roller 33 and the paper feed motor 37 are in a rotational driving force transmission relationship between the paper feed motor belt 40 and the one-way clutch.

As shown in FIGS. 1 and 11, the registration roller upper portion 31a and the registration roller lower portion 31b are integrally formed with a registration roller shaft and a registration roller shaft 31c, respectively, and both ends of each registration roller shaft 31c are formed in the housing. The body side plate is rotatably supported. A toothed registration roller pulley 43 is attached to one end of the lower registration roller shaft 31c. The lower registration roller 31b is supported by the casing side plate through a registration roller shaft 31c so as not to move and to rotate freely. The upper registration roller 31a is provided so as to be able to contact and separate through a registration roller contacting / separating means (not shown) so as to come into contact with the lower registration roller 31b at a predetermined timing.
A registration motor 41 as registration driving means for rotating the registration roller pair 31 is fixed to the casing side plate below the registration roller lower 31b. The registration motor 41 is composed of a stepping motor, for example, and a toothed registration motor pulley 42 is fixed to the output shaft thereof. Between the registration roller pulley 43 and the registration motor pulley 42, a toothed registration motor belt 44 is stretched. Accordingly, the lower registration roller 31 b and the registration motor 41 are in a rotational driving force transmission relationship via the registration motor belt 44.

In FIG. 1, a sheet for detecting the leading edge and the trailing edge of the sheet 36 fed from the registration roller pair 31 is disposed on the sheet conveyance path XA from the plate cylinder 1 and the press roller 21 to the nip portion of the registration roller pair 31. A paper detection sensor 32 is provided as detection means. In the paper detection sensor 32, the paper 36 remains in the paper transport path XA upstream from the position where the paper detection sensor 32 is disposed (position where the leading edge of the paper 36 can be detected) (jamming or the like occurs). It also has a function to detect. The paper detection sensor 32 is a reflective optical sensor.
In FIG. 14, control target drive means of the paper feed unit 30 including the paper feed tray lifting / lowering motor, the paper feed motor 37, and the registration motor 41 of the paper feed unit 30 are collectively referred to as a paper feed drive unit 125.

  As shown in FIG. 12, the image reading unit 18 includes the above-described document receiving base 134 on which a plurality of documents 133 are stacked, a contact glass 135 as a reading unit on which the document 133 is placed, and a document that conveys the document 133. A pair of transport rollers 136 and a document transport roller 137, guide plates 138 and 139 for guiding the transported document 133, a plurality of document transport belts 140 that transport the document 133 along the contact glass 135, and the read document 133 A document tray 141, a pressure plate 142 that supports each member except for the contact glass 135 and is provided so as to be able to contact / separate / open / close with respect to the contact glass 135, and scans and reads an image of the document 133 while illuminating it. Reflection mirrors 143 and 144 and a fluorescent lamp 145 for focusing the reflected light of the scanned and read image That a lens 146, and a image sensor 147 or the like provided with a CCD (charge coupled device) or the like for photoelectric conversion reflected light of the focused image.

In the above configuration, the original 133 is placed on the contact glass 135 (reading unit) by the original receiving tray 134, the original conveying roller pair 136, the original conveying roller 137, the guide plates 138 and 139, the original conveying belt 140 and the original tray 141. An automatic document feeder (hereinafter referred to as “ADF”) 148 is configured as an automatic document feeder that feeds sheets one by one. Further, a scanner device 132 as a document reading unit that reads an image of the document 133 on the contact glass 135 (reading unit) by the contact glass 135, the reflecting mirrors 143 and 144, the fluorescent lamp 145, the lens 146, and the image sensor 147, Each of the reflecting mirrors 143 and 144, the fluorescent lamp 145, and the lens 146 constitutes a document scanning optical system.
The document transport roller pair 136, the document transport roller 137, and the document transport belt 140 are driven by a document transport motor (not shown). The scanner device 132 is provided with a scanner motor (not shown) that drives the scanner device 132. The image sensor 147 performs photoelectric conversion corresponding to the received reflected light, and inputs an image signal obtained thereby to the A / D converter.

  In the vicinity of the lower part of the contact glass 135, a document vertical size detection sensor 149a that detects the length of the document in the transport direction (left-right direction) in the view of the document 133 to be transported or the document not shown placed on the contact glass 135. 149b and the document 133 to be transported or the document lateral size detection sensor (not shown) that detects the length of the front side and the back side of the paper surface in the figure of the document (not shown) placed on the contact glass 135 or both. Sensor). The document vertical size detection sensors 149a and 149b and the document horizontal size detection sensor detect the sizes of the document 133 to be conveyed or the document (not shown) placed on the contact glass 135. These are hereinafter referred to as the document size detection sensor 149. Collectively.

The original size detection sensors 149a and 149b of the original size detection sensor 149 and the original horizontal size detection sensor are both reflection-type optical sensors. The presence or absence of 133 is detected. A signal from the document size detection sensor 149 is input to the control device 100 described later. Based on the signal from the document size detection sensor 149, the control device 100 determines and recognizes the document size (when it is the same size, it is also the size of the plate-making image to be made / formed on the master 8). A document detection sensor 131 that detects the document 133 remaining on the document tray 134 is disposed below the document tray 134. The document detection sensor 131 outputs a signal to the control device 100 when the document 133 on the document tray 134 is exhausted.
In FIG. 14, the control target drive means of the image reading unit 18 including the scanner motor and the document transport motor of the image reading unit 18 are collectively referred to as a reading drive unit 128.

  With reference to FIG. 13, a detailed configuration of the operation panel 173 that instructs the double-sided stencil printing apparatus 300 to perform a predetermined operation or the like will be described. The operation panel 173 is disposed in the vicinity of the image reading unit 18 shown in FIG. The operation panel 173 has a plate making start key 174, a printing start key 175, a test printing key 176, a continuous key 177, a clear / stop key 178, a numeric key 179, an enter key 180, a program key 181, a mode clear key 182 on the upper surface of the operation panel 173. A speed setting key 183, a printing speed display device 183A composed of LEDs (light emitting diodes), a four-direction key 184, a paper size setting key 185, a paper type setting key 186, a double-sided printing key 187, a single-sided printing key 188, and a 7-segment LED. A display device 189, a display device 190 including an LCD (liquid crystal display device), and the like are included.

  The plate-making start key 174 is pressed when the double-sided stencil printing apparatus 300 performs a plate-making operation. When the plate-making start key 174 is pressed, a plate-making operation is performed after a plate-discharging operation and a document reading operation are performed. The printing operation is performed and the double-sided stencil printing apparatus 300 enters a print standby state. The print start key 175 is pressed when the duplex stencil printing apparatus 300 performs a printing operation. When the duplex start stencil printing apparatus 300 enters a print standby state and various printing conditions are set, the print start key 175 is pressed. A printing operation is performed. The trial printing key 176 is pressed when causing the double-sided stencil printing apparatus 300 to perform trial printing, and only one sheet is printed by pressing the trial printing key 176 after various conditions are set.

The clear / stop key 178 is pressed when the operation of the double-sided stencil printing apparatus 300 is stopped or when the number is cleared. The numeric keypad 179 is used for numerical input. The enter key 180 is pressed when setting a numerical value or the like at various settings, and the program key 181 is pressed when registering or calling an operation that is often performed, and the mode clear key 182 is used to clear various modes. Press to return to the initial state.
The print speed setting key 183 is pressed when setting the print speed prior to the printing operation, and when it is desired to obtain a darker image or when the ambient temperature is low, the print speed is slow and a lighter image is desired. Or, when the ambient temperature is high, the printing speed is set fast.
“Printing speed: 3rd speed” in which the printing speed of the printing speed display device 183A and the black color of the displayed central part are applied is a standard printing speed corresponding to the printing speed normally used, and the printing speed setting This is automatically set when the key 183 is not pressed. For example, the leftmost “printing speed: 1st” displayed as “slow” is the lowest printing speed of 60 sheets / min: 60 rpm, and the “printing speed: 2nd” next to the right is the printing speed. 75 sheets / min: 75 rpm, “standard printing speed: 3rd speed” is the printing speed is 90 sheets / min: 90 rpm, and “printing speed: 4th speed” next to the right is the printing speed is 105 sheets / min: 105 rpm. , “Printing speed: 5th speed” on the right side where “Hayaku” is displayed is set in correspondence with 120 sheets / min: 120 rpm, the highest printing speed. The printing speed display device 183A switches the printing speed to five levels from 1 to 5 by pressing the printing speed setting key 183 (speed up key and speed down key on the left and right) each time, and the set printing speed. Lights up.
The four-way key 184 has an up key 184a, a down key 184b, a left key 184c, and a right key 184d. When adjusting the image position during image editing or when selecting numerical values or items at various settings, etc. Pressed. The paper size setting key 185 is pressed when an arbitrary paper size is input, and the paper size input with the paper size setting key 185 has priority over the paper size detected by the paper size detection sensor 117.

The paper type setting key 186 is pressed when inputting the paper type prior to double-sided printing, and is classified into three types of “plain paper”, “thin paper”, and “thick paper”, which are also called standard papers in this embodiment, Further, any one of the paper types classified in detail corresponding to them is selected. In other words, in the present embodiment, by inputting / operating the paper type setting key 186, for example, the paper thickness among the paper types and the characteristics of the paper thickness among the strengths can be selected and set. This is based on the fact that the strength (so-called waist strength) tends to increase as the thickness of the paper increases.
Thin paper includes renewal paper and high quality 45 kg paper, and plain paper (standard paper) includes copying paper, medium quality paper, high quality 55 kg paper, recycled paper, stencil high quality paper, and the like. Examples of cardboard include drawing paper, postcards, envelopes, high-quality 135 kg paper, and high-quality 180 kg paper.

  The double-sided printing key 187 is pressed before the plate making start key 174 is pressed when the double-sided stencil printing apparatus 300 performs the double-sided printing operation, and when the double-sided printing key 187 is pressed, the LED 187a disposed in the vicinity thereof lights up. Is displayed indicating that the duplex printing mode is set. Similarly to the double-sided printing key 187, the single-sided printing key 188 is pressed before pressing the plate making start key 184 when the double-sided stencil printing apparatus 300 performs a single-sided printing operation. The arranged LED 188a is turned on to indicate that the single-sided printing mode is set. In the double-sided stencil printing apparatus 300, the LED 188a is lit in the initial state after turning on the power switch (not shown), and the single-sided printing mode is set.

The display device 189 mainly displays numbers such as the number of printed sheets. The display device 190 has a hierarchical display structure. By selecting and pressing selection setting keys 190a, 190b, 190c, and 190d provided below the display device 190, various modes such as scaling and image position adjustment are performed. Can be changed and set in each mode. Further, when the paper type setting key 186 is pressed on the display device 190, the paper type to be selected and set is displayed, or the double-sided stencil printing device 300 such as “can be made / printed” as illustrated is displayed. In addition to displaying the status, warnings such as prepress or discharge jam, paper feed or paper discharge jam, supply instructions for supplies such as paper, master, and ink are also displayed.
When the paper type setting key 186 is first pressed once, the paper types to be selected and set are as follows: thin paper: renewal paper, high quality 45 kg paper, etc., plain paper: copy paper, medium quality paper, high quality 55 kg paper, recycled paper, stencil High-quality paper, etc., thick paper: drawing paper, postcard (postcard), envelope, high-quality 135 kg paper, high-quality 180 kg paper, etc. are displayed on the display device 190. When the paper used with the four-way key 184 is selected / designated, the display device 190 Since the part of the selected / designated paper is displayed in black and white inversion above, it may be determined and set by finally pressing the enter key 180. Therefore, the paper type setting means for setting the paper type includes the paper type setting key 186, the enter key 180, and the four-direction key 184 in the above example.
The paper type setting means is not limited to the combination of the above keys. For example, the number of keys corresponding to the paper type to be selected and set is provided, or the function is assigned to the selection setting keys 190a to 190d. It may be settable.

  Next, the main control configuration of the double-sided stencil printing apparatus 300 will be described with reference to FIG. In FIG. 14, the control device 100 has functions and configurations as means for controlling mainly a document reading operation, plate making / plate feeding operation, paper feeding operation and printing operation of the double-sided stencil printing apparatus 300. The control device 100 includes a CPU 101 (central processing unit), an I / O (input / output) port (not shown), a ROM 102 (read-only storage device), a RAM 103 (read / write storage device), a timer backed up by a battery (not shown), and the like. And a microcomputer having a configuration in which they are connected by a signal bus (not shown).

  As shown in FIG. 1, the control device 100 is provided in a control board arrangement section in the main body frame 130. The CPU 101 of the control device 100 (hereinafter, sometimes simply referred to as “control device 100” for simplicity of explanation) receives various signals from the operation panel 173 and the above-described various sensors provided on the main body frame 130. Based on the detection signal and the operation program called from the ROM 102 and related data, the main motor 20 of the printing unit 16, the stepping motor 252 of the printing pressure range varying unit 28, the solenoid 62 of the locking unit 64, the plate making unit 15, the paper feed Control unit driving means provided in the image forming unit 30, the plate discharging unit 17, the paper discharging unit 19, the image reading unit 18, the press roller driving motor 55 provided in the refeeding unit 45, and the suction fan of the refeeding conveyance device 104. 109, belt drive motor 105, solenoid 73, solenoid 47 of switching guide 46, and moving means 87. Controls each operation such as dynamic motor 94, controls the duplex stencil printing device 300 overall operation. The control device 100 also determines the rotational position of the plate cylinder 1 and the printing speed based on various plate cylinder position signals from the plate cylinder position detection sensor 29 generally shown in FIG. .

The ROM 102 stores in advance an operation program for the entire duplex stencil printing apparatus 300, necessary related data, and the like, and this operation program is appropriately called by the CPU 101. The relational data includes the printing speed including the paper type including the thickness of the paper 36 and the rotational speed of the belt driving motor 105 of the paper refeeding and conveying device 104 (in other words, the conveying speed that is also the linear speed of the conveying belt 108). And the relationship data set for each printing speed between the sheet type and the stop timing of the belt drive motor 105 after contacting the front end of the front surface printed sheet 36a with the stopper surface 53a. These relational data are, for example, a data table for changing the conveyance speed of the conveyance belt 108 determined in advance for each printing speed and set according to the paper type for each printing speed. The data is stored in advance in the ROM 102 as a data table for changing the stop timing of the belt drive motor 105 set according to the type.
For example, in the case of a sheet 36 having a small thickness, such as a refill paper, the sheet weight is lighter and the sliding with respect to the conveyor belt 108 is less than a thick sheet having a sheet weight. Until the used paper 36a is released, the leading end of the paper 36a comes into contact with and stops at the stopper surface 53a of the stopper member 53 by the transport belt 108, and then is transported at a predetermined timing by the refeed resist roller 51. Is set to a conveyance speed considering the conveyance stop timing of the conveyance belt 108 described later.
When the paper 36 is light and thin, the conveyance stop timing of the conveyance belt 108 is set to be earlier, and conversely, when the paper 36 is heavy, such as heavy paper, the conveyance speed is increased in anticipation of slipping on the conveyance belt 108. As soon as possible, the conveyance stop timing is also delayed.
In addition to the ROM 102, it is possible to write the related data as necessary so as to be able to cope with, for example, a design change by arranging a storage means such as a programmable PROM. is there.
The RAM 103 has a function of temporarily storing calculation results of the CPU 101, a function of storing data signals and on / off signals set and input from various keys and various sensors on the operation panel 173 as needed.

The CPU 101 of the control device 100 (hereinafter sometimes simply referred to as “control device 100”) recognizes and grasps the rotational speed of the plate cylinder 1 as needed based on various plate cylinder position signals from the plate cylinder position detection sensor 29. In addition, the rotational position (rotational phase position) of the plate cylinder 1 is recognized and grasped in real time.
The control device 100 (CPU 101) changes the conveyance speed of the conveyance belt 108 of the refeed conveyance device 104 according to the type of paper, and after contacting (contacting) the front end of the front surface printed paper 36a with the stopper member 53. It has a function as a control means which changes the conveyance stop timing of the conveyance belt 108.
In other words, the control device 100 (CPU 101) determines the transport speed of the transport belt 108 of the refeed transport device 104 according to the paper type selected and set by the paper type setting key 186, the enter key 180, and the four-direction key 184. The belt drive motor 105 is controlled so as to change, and the belt drive motor 105 is controlled so that the conveyance stop timing of the conveyance belt 108 after the front end of the front surface printed paper 36a contacts the stopper surface 53a changes. As a function.

  More specifically, the control device 100 (CPU 101) determines the paper type for each printing speed based on the paper type data signal relating to the paper type selected and set by the paper type setting key 186, the enter key 180, and the four-direction key 184. The data table for changing the conveying speed of the conveying belt 108 set according to the data and the data table for changing the stop timing of the belt driving motor 105 are called from the ROM 102, and the rotation of the belt driving motor 105 corresponding to the paper type data is called. By extracting the speed and the stop timing after the front end of the front surface printed paper 36a abuts against the stopper surface 53a, the transport speed of the transport belt 108 corresponding to the selected paper type is selected and selected. Conveyance stop timing of the conveyor belt 108 corresponding to the set paper type Functions as a control means for controlling the belt drive motor 105 so that the.

  Based on the above-described configuration, the operation including the operation procedure of the double-sided stencil printing apparatus 300 in the present embodiment will be described with reference to FIGS. Since this operation is performed under the control of the control device 100, when explaining detailed operations such as activation, operation, and stop of actuators (control target drive means) such as various motors and various solenoids, the control device 100 The expression based on the command or the command signal is omitted as much as possible.

(Operation example 1)
First, an operation example 1 in which the simplex printing mode is set and the simplex printing is performed will be described. The operation example 1 is substantially the same as the operation for performing single-sided printing by a conventional stencil printing apparatus, and is substantially the same as the operation for performing single-sided printing disclosed in Japanese Patent Application Laid-Open No. 2003-200355 (Patent Document 7). Because there is, it explains briefly. In the single-sided printing operation, the printing pressure range pattern III is used, and the cam plate 243A for normal printing is selected and used from among the components of the printing pressure range variable means 28. In the first operation example, in order to facilitate understanding of each operation, the A3 size is used as the master size, and the A3 size is used as the document size and the paper size.
The user loads A3 size paper 36 as a paper size used for printing on the paper feed tray 35, opens the pressure plate 142, and places an A3 size document to be printed on the contact glass 135, and then again. The pressure plate 142 is closed. Thereafter, after making plate making conditions with various keys on the operation panel 173, the simplex printing key 188 is pressed to set the simplex printing mode.

The user confirms the single-sided printing mode by turning on the LED 188a, and then presses the plate making start key 174. When the plate making start key 174 is pressed, a paper size detection signal is sent from the paper size detection sensor 117 and a document size detection signal is sent from the document size detection sensor 149 to the control device 100. Compare each signal. At this time, if the paper size and the document size are the same, the image reading operation is immediately performed. If the paper size and the document size are different, the control device 100 displays the fact on the display device 190 and pays attention to the user. Prompt.
In the single-sided printing mode setting state, the switching guide 46 is stopped and held at the first displacement position (initial position) shown in FIG. When a plate making start key 174 is pressed to generate a start signal and this is input to the control device 100, a series of operations from plate discharge to paper discharge are automatically performed. Prior to this, when the paper feed tray lifting / lowering motor is turned on, the paper feed tray 35 is raised, and the uppermost paper 36 comes into contact with the paper feed roller 33, so that a paper feed position detection sensor (not shown) is turned on. When the control device 100 determines that the uppermost sheet 36 is ready to be fed by the detection, the sheet feeding device 30 enters a sheet feeding standby state.

  First, in the plate removal unit 17, a plate removal operation for peeling the used master from the outer peripheral surface of the plate cylinder 1 is performed. When the start signal is input to the control device 100, the plate cylinder 1 starts to rotate. When the plate cylinder 1 reaches the home position where the clamper 7 is almost directly above, the operation of the main motor 20 is stopped and the plate cylinder 1 is stopped. 1 stops at the plate removal position. Next, the plate discharge driving means 126 is operated to rotate the drive rollers 164 and 167, and the lower plate discharge member 161 is moved to the plate cylinder 1 side, so that the endless belt 169 located on the outer peripheral surface of the driven roller 168 is moved. Abuts the used master. When the main motor 20 is started following the operation of the plate discharge driving means 126, the used master scooped up from the outer peripheral surface of the plate cylinder 1 by the rotation of the plate cylinder 1 and the movement of the endless belt 169 is the lower plate discharging member. 161 and the upper plate removal member 160 are nipped and conveyed and peeled from the outer peripheral surface of the plate cylinder 1. The peeled used master is discarded in the discharge box 162 and then compressed by the compression plate 163.

Even after all the used masters are peeled off from the outer peripheral surface, the plate cylinder 1 continues to rotate, and stops until the clamper 7 is rotated to the plate feed standby position located almost directly above. At the same time, an opening / closing device (not shown) is operated to open the clamper 7, and the double-sided stencil printing device 300 enters a plate-feed standby state.
In parallel with the plate discharging operation, a document image reading operation is performed by the image reading unit 18. The original image is read by reflecting the reflected light illuminated by the fluorescent lamp 145 by the respective reflecting mirrors 143 and 144, and the reflected light related to the read original image is focused by the lens 146 and then image sensor 147. And is photoelectrically converted. The photoelectrically converted electrical signal is input to the A / D converter (not shown) in the main body frame 130, and then passes through a plate making control device (not shown) (which may be arranged in the control device 100). It is transmitted to a thermal head drive circuit (not shown).

  In parallel with the plate discharging operation and the image reading operation, the plate making unit 15 performs the plate making operation. That is, a digital image signal for controlling the heat generation of the heat generating elements of the thermal head 11 is transmitted to the thermal head 11 via the plate making control device and the thermal head driving circuit. As a result, a large number of heating elements of the thermal head 11 are energized in pulses in the main scanning direction to selectively generate heat, and the master transport motor 10 is driven to rotate, whereby the platen roller 9 and the transport roller pair 13 are driven. Starts rotating, and the thermoplastic resin film portion of the master 8 is selectively heated and punched according to image information while the master 8 is pulled out from the master roll 8a and is transported in the master transport direction X1.

Then, the leading end of the master-made master 8Y is inserted between the clampers 7 that are guided by the master guide plate 14 and expanded with respect to the stage 6, and the number of steps of the master transport motor 10 reaches a certain set value, When it is determined that the leading end of the master-making master 8Y has reached between the stage 6 and the clamper 7, the clamper 7 is closed by the opening / closing device, and the leading-end of the master-making master 8Y is between the stage 6 and the clamper 7. Adsorbed and pinched by
After clamping the front end of the master 8Y, the plate cylinder 1 resumes rotation at the same peripheral speed as the master transport speed by the rotation of the main motor 20, so that the master 8Y is ready for the platen roller 9 and the transport roller pair 13. Is fed to be wound around the outer peripheral surface of the plate cylinder 1. When it is determined that the plate making to the master 8 and the carrying of the set amount of the plate-making master 8Y have been completed by the rotation driving of the master carrying motor 10 by a predetermined number of steps, the cutter 12 is operated to cut the plate-making master 8Y. At the same time, the rotation of the platen roller 9 and the conveyance roller pair 13 is stopped by stopping the rotation of the master conveyance motor 10. When the rear end of the cut master 8Y is drawn out of the plate making unit 15 by the rotation of the plate cylinder 1 and completely wound around the outer peripheral surface of the plate cylinder 1, the master 8Y is transferred to the plate cylinder 1. When the winding of is finished, the plate feeding operation is finished.

  When winding of the plate-making master 8Y around the plate cylinder 1 is completed, the plate cylinder 1 starts to rotate at a predetermined peripheral speed in the direction of the arrow shown in FIG. Be started. It should be noted that the solenoid 62 of the locking means 64 is turned off by the control device 100 until the leading edge of the paper 36 crosses / passes the paper detection sensor 32, that is, until the leading edge of the paper 36 is detected to be ON by the paper detection sensor 32. Therefore, the printing pressure range variable means 28 is in a non-operating state, so that the press roller 21 is held at a non-printing position, that is, an initial position separated from the outer peripheral surface of the plate cylinder 1.

When the plate cylinder 1 rotates at a low speed in the direction of the arrow, first, the sheet feeding start light shielding plate 121 shown in FIG. 10 is engaged with the sheet feeding registration sensor 120, so that the sheet feeding registration sensor 120 is turned on. A paper start signal is generated, and this signal is used as a trigger to start the paper feed motor 37 (start rotation driving). When the paper feed motor 37 is driven to rotate clockwise in FIG. 11, the paper feed roller shaft 33a and the paper feed roller 33 are rotated clockwise through the operation of the mechanism shown in FIG. The uppermost sheet 36 on the sheet feed tray 35 in contact with the sheet 33 is separated into one sheet by the cooperative action with the separating member 34 while being conveyed, and the registration roller pair 31 on the downstream side in the sheet conveying direction X is separated. It is fed toward the nip part.
Next, when the plate cylinder 1 further rotates in the direction of the arrow in FIG. 1 and the resist start light shielding plate 122 engages with the paper feed resist sensor 120, the paper feed resist sensor 120 is turned on and a resist start signal is generated. Then, this signal is used as a trigger to activate the registration motor 41. The timing at which the registration motor 41 is activated, in other words, the timing at which the lower registration roller 31b is rotated is the image area of the single-side plate-making image 8YA in the plate-cylinder rotation direction of the plate-making master 8Y wound on the plate cylinder 1. It is set at a predetermined timing when the tip portion reaches a position corresponding to the press roller 21.

The registration motor 41 is driven to rotate counterclockwise in FIG. 11, and the registration lower shaft 32a and the registration roller lower 31b rotate counterclockwise through the operation of the mechanism shown in FIG. The leading edge of the paper 36 that is in contact with and waiting at the portion is fed while being pressed by the registration roller top 31 a and is sent out between the plate cylinder 1 and the press roller 21.
Next, the leading edge of the sheet 36 fed by the registration roller pair 31 is normally entered, that is, the leading edge of the sheet 36 is within a predetermined time counted by the timer (or a predetermined amount supplied to the registration motor 41). This signal is input to the control device 100 when the paper detection sensor 32 detects the ON state within the number of pulses. Based on the detection signal of the leading edge of the sheet 36 from the sheet detection sensor 32 and the rotational position information of the plate cylinder 1 from the plate cylinder position detection sensor 29, the control device 100 instructs the solenoid 62 of the locking means 64 to energize. When the solenoid 62 is turned on, the cam plate 243A of the printing pressure range varying means 28 is operated.
When the solenoid 62 is turned on, the plunger 62a is sucked, whereby the locking member 60 swings counterclockwise about the support shaft 61 against the urging force of the tension spring 63, and the locking claw 60a has a notch 22b. The other end portion side of the printing pressure arm 22 that is locked is released and rocked clockwise around the arm shaft 22a by the urging force of the printing pressure spring 242. By swinging the other end of the printing pressure arm 22, the outer peripheral surface of the cam follower 241 is opposed to the peripheral surface of the small-diameter portion of the cam plate 243A rotating in synchronization with the rotation of the plate cylinder 1. At the rotational position of the cam plate 243A (for example, the rotational position shown by borrowing FIG. 3), the printing pressure arm pair 22 is swung clockwise by the urging force of the printing pressure spring 242 about the arm shaft 22a. .

  As a result, as shown in FIG. 9, the press roller 21 has a single-side plate-making image 8YA of the plate-making master 8Y whose outer peripheral surface is wound on the surface region 1A or the back surface region 1B of the plate cylinder 1 shown in FIG. The nip portion 16a (see, for example, FIG. 3) is formed by displacing the paper 36 to a printing position where the printing pressure is applied by pressing the paper 36 slightly toward the left end of the margin. At the same time, the press roller drive motor 55 rotates the press roller 21 at a substantially same peripheral speed as the peripheral speed of the plate cylinder 1, so that the press roller 21 rotates in the direction opposite to the rotation direction of the plate cylinder 1. By continuously pressing the sheet 36 against the plate-making master 8Y on the plate 1, the plate-making master 8Y is brought into close contact with the outer peripheral surface of the plate cylinder 1 and so-called printing is performed to fill the ink. In this printing, stencil printing is performed by the ink oozing from the opening portion of the opening portion 1a of the plate cylinder 1 to the punching portion of the master-making master 8Y and transferred to the surface of the paper 36.

At this time, the ink roller 2 also rotates in the same direction as the rotation direction of the plate cylinder 1. The ink in the ink reservoir 4 is adhered to the surface of the ink roller 2 by the rotation of the ink roller 2, and the amount of the ink is regulated when passing through the gap between the ink roller 2 and the doctor roller 3. To be supplied. On the other hand, in conjunction with the raising and lowering operation of the press roller 21, the refeed conveyance device 104 swings about the drive shaft 107 a via the refeed housing 110. In the single-sided printing mode, the belt driving motor 105 and the suction fan 109 of the refeed conveyance device 104 remain in an inoperative state, the driving motor 94 of the moving unit 87 also remains in an inoperative state, and the moving guide 81 is The initial position P2 is still occupied.
Thus, plate printing corresponding to the single-side plate-making image 8YA on the plate-making master 8Y on the plate cylinder 1 is performed. The peripheral surface of the large-diameter portion of the cam plate 243A rotating in synchronization with the plate cylinder 1 comes into contact with the outer peripheral surface of the cam follower 241. As a result, the printing pressure arm pair 22 swings and displaces counterclockwise against the urging force of the printing spring 242 around the arm shaft 22a, and the press roller 21 moves downward to occupy the non-printing position. Thus, the printing pressure application state by the press roller 21 is released.
When the plate cylinder 1 rotates in the direction of the arrow in FIG. 1 and the clamper 7 reaches the vicinity of the press roller 21 in pressure contact with the plate cylinder 1, the plate cylinder 1 is driven to rotate in synchronization with the rotation of the plate cylinder 1. Since the cam plate 243A rotates the peripheral surface of the large diameter portion to a position where it abuts on the outer peripheral surface of the cam follower 241, the press roller 21 is separated from the clamper 7 protruding outward from the outer peripheral surface of the plate cylinder 1. Thus, interference between the press roller 21 and the clamper 7 can be avoided.

The single-sided printed paper 36 c that has been subjected to plate printing is further conveyed by the rotation of the plate cylinder 1 in the direction of the arrow in FIG. 1 while being pressed by the press roller 21, and the leading edge of the single-sided printed paper 36 c is located on the plate cylinder 1. The air blow from the peeling claw 170 and the peeling fan 171 approaching the outer peripheral surface is surely peeled off from the plate-making master 8Y on the plate cylinder 1, and the peeled single-sided printed paper 36c falls downward and is discharged. The sheet is conveyed to the sheet discharge belt 158 of 152 and is attracted to the upper surface of the sheet discharge belt 158 rotating in the direction of the arrow (counterclockwise) in FIG. The paper is conveyed to the downstream side and discharged to the paper discharge tray 172 with its both ends aligned by a pair of paper discharge side fences 172a and 172b.
On the other hand, when the press roller 21 comes into contact with the outer peripheral surface of the plate cylinder 1, the plate cylinder 1 makes approximately three quarters of a turn, and when the large-diameter portion peripheral surface of the cam plate 243 </ b> A comes into contact with the cam follower 241, At the time when the pawl 60a and the notch 22b of the printing pressure arm 22 can be locked, the energization to the solenoid 62 is interrupted (turned off) by a command from the control device 100. Then, the locking member 60 is swung clockwise around the support shaft 61 by the urging force of the tension spring 63, and the notch 22b of the printing pressure arm 22 is locked to the locking claw 60a. As a result, the press roller 21 is returned to and held in the non-printing position away from the outer peripheral surface of the plate cylinder 1, and the plate cylinder 1 is rotated to the home position again and stopped. The stencil printing apparatus 300 enters a print standby state.
Further, during paper feeding or plate-making, the platen roller 9 and the conveying roller pair 13 resume rotation, and the leading end of the cut master 8 is sent toward the nip portion of the conveying roller pair 13. If it is determined from the number of pulses of the master transport motor 10 that the tip of the cut master 8 has reached the nip portion of the transport roller pair 13 and has been sandwiched, the rotation of the platen roller 9 and the transport roller pair 13 stops, and the next It will be in the state of waiting for plate making in preparation for plate making.

  After the duplex stencil printing apparatus 300 enters a print standby state, when a printing condition is input using the printing speed setting key 183 and various keys on the operation panel 173 and the trial printing key 176 is pressed, the trial printing is performed. When the trial printing key 176 is pressed, the plate cylinder 1 is driven to rotate at the set printing speed, and one sheet of paper 36 is fed from the paper feeding unit 30. The fed paper 36 is temporarily stopped by the registration roller pair 31 and then fed at the same timing as that at the time of printing. The press roller 21 is pressed against the plate-making master 8Y on the outer peripheral surface of the plate cylinder 1. The single-sided printed paper 36c on which the printed image is formed is surely peeled off from the plate-making master 8Y on the plate cylinder 1 by the peeling claw 170 and the peeling fan 171, and the peeled single-sided printed paper 36c is discharged. The paper is transported by the paper transport device 152 in the same manner as described above and discharged onto the paper discharge tray 172.

  Along with the set printing speed, control target drive means such as various motors such as printing pressure range variable means 28, paper feed unit 30, paper discharge conveyance device 152, and various solenoids are driven at speeds and timings suitable for the print speed. Be controlled. When the position or density of the image is confirmed by trial printing, and the print start key 175 is pressed after the number of prints is input by the numeric keypad 179, the paper 36 is continuously fed from the paper supply unit 30, and the trial printing is performed. The printing operation is performed under the same conditions. When the set number of prints is exhausted, the plate cylinder 1 stops at the home position, and the double-sided stencil printing apparatus 300 enters the print standby state again. Compared with the printing operation at the time of printing, the normal printing operation does not count the number of sheets 36 used for printing as described above as a normal normal printing number, and the setting desired by the user The only difference is that the operations of paper feeding, printing, and paper discharge are performed at a speed corresponding to the printing speed.

  A sheet detection means corresponding to the sheet detection sensor 32 as described above is arranged on the conveyance path so as to detect the leading edge and the trailing edge of the surface printed sheet 36a that is held on the outer peripheral surface of the press roller 21 and conveyed to the nip portion 16a. You may arrange in. The reading operation in the image reading unit 18 may use ADF 148 in addition to the above. The difference from the operation example 1 in this case is as follows. That is, when an A3-size document 133 is set on the document tray 134 of the ADF 148 by the user, the ADF 148 of the image reading unit 18 is operated in parallel with the plate removal operation, so that one document 133 is read by the reading unit. The only difference is that it is delivered onto a certain contact glass 135. After that, as described above, the image of the original 133 is read as optical information by the operation of the scanner device 132.

(Operation example 2)
Next, an operation example 2 in which the duplex printing mode is set and duplex printing is performed will be described. In the operation example 2, all the printing pressure range patterns I, II, and III shown in FIG. 9 are used. For this reason, all of the three cam plates 243A, 243B, 243C of the multistage cam 243 constituting the constituent elements of the printing pressure range varying means 28 are used. In operation example 2, in order to facilitate understanding of each operation, a master size of A3 is used, and a document size and a paper size of A4 are used. Hereinafter, the points different from the operation example 1 will be mainly described.

The user stacks A4 size paper 36 as a paper size used for printing on the paper feed tray 35, opens the pressure plate 142, and places the first A4 size original for surface printing on the contact glass 135. After placing, the pressure plate 142 is closed again. After that, the user presses the paper type setting key 186 on the operation panel 173 to display all the paper types used in the double-sided stencil printing apparatus 300 on the display device 190 and then use the four-way key 184 for double-sided printing. As the paper type, for example, “replacement” classified as thin paper is displayed in black and white reversed and finally determined by the enter key 180 to select and set. Furthermore, after setting the plate making and printing conditions with various keys on the operation panel 173, the duplex printing key 187 is pressed to set the duplex printing mode, and then the duplex printing mode is confirmed by turning on the LED 187a. Next, when the plate making start key 174 is pressed, a start signal is generated as in the single-sided printing mode, and this is input to the control device 100.
Similarly to the first operation example, a paper size detection signal is sent from the paper size detection sensor 117 and a document size detection signal is sent from the document size detection sensor 149 to the control device 100, and the control device 100 receiving these signals receives each signal. Compare signals. In this embodiment, since the maximum paper size that can be printed by the plate cylinder 1 during single-sided printing is A3 size, the paper size that can be used during double-sided printing is up to A4 portrait.
As a result of comparing the document size and the paper size, if the two sizes are the same, the image reading operation is immediately performed. If the two sizes are different, the control device 100 displays a warning on the display device 190 as a warning. Call attention to the user. When the paper size exceeds A4 portrait orientation, the control device 100 prohibits the double-sided printing operation and causes the display device 190 to display a message that prompts single-sided printing.

When the plate making start key 174 is pressed, a series of operations from discharging to discharging are automatically performed as in the first operation example. Similarly to the first operation example, when the control device 100 determines that the uppermost sheet 36 of the sheet feeding tray 35 is ready to be fed, the sheet feeding unit 30 enters a sheet feeding standby state. After the plate removal operation similar to that in Operation Example 1 is performed, the plate cylinder 1 from which all used masters have been peeled off from the outer peripheral surface is stopped at the plate feed standby position as in Operation Example 1, and is opened and closed (not shown). The clamper 7 is opened by the device.
In part in parallel with this plate discharging operation, the image reading unit 18 performs the reading operation of the first original image for front surface printing in the same manner as in Operation Example 1, and the image data signal passes through the plate making control device or the like. Transmitted to the thermal head driving circuit. In parallel with the image reading operation, the plate making unit 15 performs plate making by the thermal head 11 as in the first operation example, and the master 8 is pulled out from the master roll 8a by the rotation of the platen roller 9 and the conveying roller pair 13. While being transported in the master transport direction X1, the thermoplastic resin film portion of the master 8 is selectively heated and punched according to image information, and a surface plate-making image 8A for surface printing is formed in the first half of the master 8. (See the divided master-making master 8X shown in FIG. 9).
Then, the leading end of the divided plate-making master 8X is inserted between the clampers 7 which are guided by the master guide plate 14 and expanded with respect to the stage 6, and the number of steps of the master transport motor 10 reaches a certain set value. When it is determined that the leading end of the divided plate-making master 8X has reached between the stage 6 and the clamper 7, the clamper 7 is closed by the opening / closing device, and the leading end of the divided plate-making master 8X is moved to the stage 6 and the clamper 7. Adsorbed and pinched between.

After clamping the front end of the divided plate-making master 8X, the plate cylinder 1 resumes rotating at the same peripheral speed as the master conveyance speed by the activation of the main motor 20, and the divided plate-making master 8X moves the platen roller 9 and the conveyance roller pair. 13 is fed to be wound around the outer peripheral surface of the plate cylinder 1. When the controller 100 determines that the plate making of the surface plate making image 8A of the divided plate making master 8X shown in FIG. 9 is completed by the number of steps of the master carrying motor 10, the platen roller 9, the carrying roller pair 13, and the plate The rotation of the cylinder 1 is stopped, and a plate-making standby state for plate-making of the back-side plate-making image 8B for back-side printing in the next divided plate-making master 8X is entered.
Next, the user opens the pressure plate 142 again, places a second A4 size original for printing on the contact glass 135, and then closes the pressure plate 142 again. Thereafter, when the plate making start key 174 is pressed again, a start signal is generated and input to the control device 100. At this time, as in the case of the first document, the control device 100 compares the document size with the paper size and performs the same processing operation as described above. In the image reading unit 18, the reading operation of the second original image for back side printing is performed in the same manner as the case of the first original, and the image data signal passes through the plate making control device (not shown) or the like. It is transmitted to the thermal head drive circuit. In the plate making unit 15, the plate making by the thermal head 11 is performed as in the case of the first document, and the platen roller 9 and the pair of carry rollers 13 are rotated by the master carrying motor 10 being rotated again. The thermoplastic resin film portion of the master 8 is selectively heated and punched in accordance with image information while the master 8 is being pulled out from the master roll 8a and being transported in the master transport direction X1, and the back surface is formed on the back surface of the master 8 A back side plate-making image 8B for printing is formed (see FIG. 9).

At this time, the plate cylinder 1 resumes rotating at the same peripheral speed as the master conveyance speed, so that the latter half of the divided plate-making master 8X is wound around the outer peripheral surface of the plate cylinder 1 while being drawn out from the plate-making part 15. To go. Then, when the controller 100 determines that the last plate making image 8B of the divided plate making master 8X is completed by the number of steps of the master transport motor 10, the cutter 12 is activated and the divided plate making master is completed. The rear end portion of 8X is cut, the rotation of the platen roller 9 and the conveying roller pair 13 is stopped, and the rear end of the divided plate-making master 8X for one plate cut by the rotation of the plate cylinder 1 is the plate making section 15. The drawing / feeding operation of the divided master-making master 8X to the plate cylinder 1 is completed.
The document image reading operation and the image data inputting operation are not limited to the above-described example. For example, the document 133 is automatically conveyed onto the contact glass 135 using the ADF 148, or the image is input from an external device (not shown). You may make it take in data.
In this embodiment, when the plate making of the front plate making image 8A in the divided plate making master 8X is completed, the plate making standby state for making the back plate making image 8B for back printing in the next divided plate making master 8X is set. Accordingly, the rotation of the platen roller 9 and the conveying roller pair 13 and the plate cylinder 1 in the plate making unit 15 is temporarily stopped, but it is desirable to do as follows. In other words, in addition to the automatic conveyance operation of the original 133 by the ADF 148, an image memory (not shown) including, for example, a bitmap memory or the like that scans a second original in advance and stores and stores image data related to the read original image. If the first and second image data are stored and stored in the image memory, and the plate making is performed continuously while sequentially calling the image data, the plate making time can be shortened. And from the viewpoint of shortening the first print time (FPT).

The printing operation is performed following the plate feeding operation. When the plate cylinder 1 stops at the home position, the control device 100 activates the printing pressure range variable means 28. In the following, when the printing corresponding to the surface plate-making image 8A in the divided plate-making master 8X on the plate cylinder 1 or the surface printing in the regular double-sided printing operation is first performed, the mark shown in FIG. The printing pressure range variable means 28 is controlled so that the printing pressure ON timing by the press roller 21 in the pressure range pattern I is selected. That is, the stepping motor 252 shown only in FIG. 14 is rotationally driven and undergoes a well-known detailed operation through the rotation of the step cam (49), the cam plate 243B is selected, and the contour peripheral surface of the cam plate 243B is the cam follower 241. Abut.
When the winding of the divided plate-making master 8X to the plate cylinder 1 is completed, the plate cylinder 1 starts to rotate in the direction of the arrow shown in FIG. 3 at a predetermined peripheral speed (usually a low speed for printing). Then, a paper feeding / printing process for printing is started. As in the first operation example, until the leading edge of the paper 36 is detected to be turned on by the paper detection sensor 32, the solenoid 62 of the locking means 64 is controlled to be turned off, so that the printing pressure range variable means 28 is not turned on. The press roller 21 is held in the non-printing position.

As the plate cylinder 1 rotates in the direction of the arrow, as in the first operation example, first, the paper feeding start light shielding plate 121 shown in FIG. The uppermost first sheet 36 on the sheet feeding tray 35 that is in contact with the sheet feeding roller 33 is conveyed to be separated into one sheet by the cooperative action with the separation member 34 while being conveyed. It is sent out toward the nip part.
After the leading edge of the sheet 36 thus fed comes into contact with the nip portion of the registration roller pair 31, the sheet 36 is held in a state where a predetermined curved deflection is formed at the leading end portion of the sheet 36. Next, when the plate cylinder 1 further rotates in the direction of the arrow in FIG. 1 and the registration start light shielding plate 122 engages with the paper feeding registration sensor 120, the registration motor 41 is started in the same manner as in the first operation example. The leading edge of the sheet 36 that has been in contact with the nip portion of the registration roller pair 31 and is waiting is sent out between the plate cylinder 1 and the press roller 21 by the rotation of the registration roller pair 31 at a predetermined timing. It is. At this time, as in the operation example 1, the approach of the leading edge of the paper 36 fed by the registration roller pair 31 is normally detected by the paper detection sensor 32.

Next, based on the detection signal of the leading edge of the paper 36 from the paper detection sensor 32 and the rotational position information of the plate cylinder 1 from the plate cylinder position detection sensor 29, the control device 100 turns on the solenoid 62 as in the first operation example. Thus, the cam plate 243B of the printing pressure range varying means 28 is operated. When the solenoid 62 is turned on, the detailed operation of the locking means 64 similar to that of the operation example 1 is performed, the contour peripheral surface of the cam plate 243B abuts the outer peripheral surface of the cam follower 241, and the outer peripheral surface of the cam follower 241 is the cam. At the rotational position of the cam plate 243B facing the small-diameter peripheral surface of the plate 243B and in a non-contact state, the printing pressure arm pair 22 swings clockwise around the arm shaft 22a by the biasing force of the printing pressure spring 242. Will rise.
As a result, as shown in FIG. 9, the press roller 21 has a slightly smaller outer surface than the surface plate-making image 8A of the divided plate-making master 8X wound on the surface region 1A of the plate cylinder 1 shown in FIG. The paper 36 is pressed against the left end margin and is displaced to a printing position where printing pressure is applied to form a nip portion 16a (printing pressure by the press roller 21 in the printing pressure range pattern I shown in FIG. 9). See on-timing). At the same time, the press roller drive motor 55 rotates the press roller 21 at a substantially same peripheral speed as the peripheral speed of the plate cylinder 1, so that the press roller 21 rotates in the direction opposite to the rotation direction of the plate cylinder 1. By continuously pressing the sheet 36 against the surface plate-making image 8A portion of the divided plate-making master 8X, the surface plate-making image 8A of the divided plate-making master 8X is brought into close contact with the outer peripheral surface of the plate cylinder 1 and filled with ink. So-called printing is performed. In this plate printing, ink oozes out from the opening portion of the opening portion 1a of the plate cylinder 1 to the perforated portion of the surface plate-making image 8A in the divided plate-making master 8X and is transferred to the surface of the sheet 36, thereby making the stencil plate. Printing is performed.

At this time, the ink roller 2 is also rotated in the same direction as the rotation direction of the plate cylinder 1 as in the first operation example, whereby the ink in the ink reservoir 4 is supplied to the inner peripheral surface of the plate cylinder 1. Thus, plate printing corresponding to the surface plate-making image 8A in the divided plate-making master 8X on the plate cylinder 1 is performed, the plate cylinder 1 further rotates, and the portion near the rear end of the surface plate-making image 8A corresponds to the nip portion 16a. When the rotation position is reached, the circumferential surface of the large diameter portion of the cam plate 243B and the cam follower 241 come into contact with each other, whereby the printing pressure arm 22 rotates counterclockwise about the arm shaft 22a, and the press roller 21 does not print. Holds the position occupied. At this time, since the solenoid 62 of the locking means 64 has already been turned off by a command from the control device 100, the press roller 21 is returned to and held in the initial position state in which the non-printing position is occupied.
In parallel with the printing operation, the solenoid 47 is turned on when the clamper 7 of the plate cylinder 1 passes over the press roller 21 occupying the non-printing position, whereby the switching guide 46 is shown in FIG. Thus, it is swung counterclockwise around the shaft 47a and occupies the second displacement position and stops. At the same time, when the drive motor 94 of the moving means 87 is activated (for example, forward rotation driving is started), the movement guide 81 is also printed by printing from the initial position (standby position) P2 as shown in FIG. In order to sandwich the leading end of the printed paper 36a, the four protrusions 81c are guided and moved along the guide groove 88 and move upward and diagonally to the right so as to occupy the movement position P1. When the movement guide 81 occupies the movement position P1 by the number of steps of the drive motor 94 reaching a certain set value, the lower release lever 83 is placed on the contour peripheral surface of the release cam 98 as shown by the solid line in FIG. By sliding on and sliding, the clamp claw 81b swings clockwise and stops in a state where it is released from the contact state with the upper surface of the clamping table 81f.

When the movement guide 81 occupies the movement position P1 and stops, as shown in FIG. 3, the leading edge of the front surface printed paper 36a occupies the second displacement position and stops at the switching guide 46 and the peeling fan 171. By the operation of (see FIG. 1), it is reliably peeled off from the divided master-making master 8X (see FIG. 9) on the plate cylinder 1. The front end portion of the peeled surface-printed paper 36a is guided by the inclined surface of the clamp claw 81b provided on the movement guide 81, and the gap portion between the upper surface of the clamping table 81f and the free end of the clamp claw 81b that is opened. And then abuts against the sheet abutting surface 81e of the end fence 81d so that the leading ends are abutted and aligned. When the front end of the front surface printed paper 36a is inserted into the gap between the upper surface of the clamping table 81f and the free end of the clamp claw 81b, the drive motor 94 moves the transport speed of the front surface printed paper 36a (the plate cylinder 1 and the press). The movement guide 81 starts to move diagonally downward to the left in the drawing toward the initial position P2 by being activated (for example, reverse rotation driving is started) so as to be substantially the same speed as the circumferential speed by the rotation with the roller 21). To do.
At this time, in FIG. 8, when the lower release lever 83 is disengaged from the contour peripheral surface of the release cam 98, the clamping pawl 81b swings counterclockwise by the biasing force of the torsion coil spring, and the free end of the clamping pawl 81b. And the top end of the surface-printed paper 36a are clamped and clamped between the upper surface of the clamping table 81f. As described above, the movement guide 81 is in a state in which the front end portion of the front surface printed paper 36a is fixed and the front end of the front surface printed paper 36a is abutted against the paper contact surface 81e. It moves to the left diagonally downward in the figure toward the initial position P2 at the same movement speed as the transport speed of.
As described above, after the plate printing corresponding to the surface plate-making image 8A in the divided plate-making master 8X on the plate cylinder 1 is finished, the press roller 21 is returned to and held in the initial position occupied by the non-printing position. In a paper feed standby state for the next paper feed.

On the other hand, referring to FIG. 4, the surface-printed paper 36a is initially in a state of being clamped and fixed between the free end of the clamp claw 81b of the movement guide 81 and the upper surface of the clamping table 81f by the operation of the moving means 87. When the transfer guide 81 occupies the initial position P2 and is stopped toward the position P2, the release lever upper 82 comes into contact with the release pin 99 as shown by a two-dot chain line in FIG. As the clamp claw 81b is swung clockwise, the front end portion of the surface-printed paper 36a is released from the sandwiched / fixed state.
At this time, after the rear portion of the surface-printed paper 36a is sucked and held by the operation of the paper refeeding / conveying device 104, the front-end portion of the surface-printed paper 36a is formed between the free end of the clamp claw 81b and the upper surface of the clamping table 81f. It is desirable to open the sheet 36a in order to reduce the fluctuation of the sheet 36a and improve the positional accuracy of the sheet 36a, and to keep the subsequent printing position deviation to a minimum.
The solenoid 47 is turned off when the rear end of the front surface printed paper 36a passes the switching guide 46, so that the switching guide 46 is centered on the shaft 47a as shown by the solid line in FIG. 1 by the urging force of the tension spring. It is controlled to swing clockwise and return to the first displacement position (initial position) and stop.

  The front-side printed paper 36a whose leading end is opened is driven by the suction fan 109 of the re-feed conveyance device 104 in response to a command from the control device 100 (CPU 101), so that the non-printed image surface on the back surface is conveyed on the conveyance belt. As shown in FIG. 4, immediately after the belt drive motor 105 is driven to rotate at a specific rotational speed corresponding to the paper type, Is temporarily stopped at this timing, that is, the conveyance belt 108 has been printed on the surface at a conveyance speed corresponding to the paper type (for example, a sheet change in this operation example) through the clockwise rotation of the rear 107 of the conveyance roller. The sheet 36a is conveyed so that the tip of the sheet 36a contacts the stopper surface 53a. By stopping the conveyance at the appropriate timing, the belt drive motor is configured so that the occurrence of bending of the front end of the front surface printed paper 36a is minimized by the energy when the front surface printed paper 36a contacts the stopper surface 53a. 105 is controlled.

Next, based on the rotational position information of the plate cylinder 1 from the plate cylinder position detection sensor 29, the surface of the plate cylinder 1 corresponds to a predetermined position, that is, the reverse side plate-making image 8B in the divided plate-making master 8X on the plate cylinder 1. When the control device 100 determines that the rotational position of the plate cylinder 1 that enables printing on the back surface of the used paper 36a has been reached, the solenoid 73 is turned on, whereby the re-feeding registration roller 51 is turned on by the press roller 21. Is lifted toward the outer peripheral surface of the sheet, so that the front end portion of the surface-printed paper 36a is released from the contact state with the stopper surface 53a and pressed against the outer peripheral surface of the press roller 21. At the same time, the press roller drive motor 55 shown in FIG. 2 is rotationally driven, whereby the press roller 21 is rotated counterclockwise, whereby the surface-printed paper 36a is counterclockwise. While being pressed and clamped between a press roller 21 that rotates clockwise and a refeed resist roller 51 that rotates in the clockwise direction, the rotational speed of the press roller 21 is substantially the same as the peripheral speed of the plate cylinder 1. At a peripheral speed, the roller guide plate 50 is guided by the roller guide plate 50 so as to be conveyed along the outer peripheral surface of the press roller 21, and is brought into contact with the nip portion 16a formed by press contact between the plate cylinder 1 and the press roller 21. It is conveyed while being turned upside down.
At this time, when performing printing corresponding to the back side plate-making image 8B in the divided plate-making master 8X on the plate cylinder 1 or back side printing in a regular double-sided printing operation described later, it is shown in FIG. The printing pressure range variable means 28 is controlled so that the printing pressure ON timing by the press roller 21 in the printing pressure range pattern II is selected. That is, the stepping motor 252 shown only in FIG. 14 is rotationally driven, and through a known detailed operation through the rotation of the step cam (49), the cam plate 243C is selected, and the contour peripheral surface of the cam plate 243C is the cam follower 241. Abut.

In parallel with this conveyance, when the predetermined rotation position of the plate cylinder 1, that is, the vicinity of the front end of the back plate-making image 8B on the divided plate-making master 8X on the plate cylinder 1 reaches the rotation position corresponding to the nip portion 16a. When the small diameter portion of the cam plate 243C rotating in synchronism with the rotation of the plate cylinder 1 is in a non-contact state facing the cam follower 241, the press roller 21 has an outer peripheral surface as shown in FIG. 4, the back surface of the surface-printed paper 36a (upper surface in FIG. 4) is formed at the front end portion slightly to the left of the back plate-making image 8B of the divided plate-making master 8X wound on the back surface area 1B of the plate cylinder 1 shown in FIG. Is pressed and displaced to a printing position where printing pressure is applied, and the nip portion 16a is formed by the urging force of the printing pressure spring 242 to perform double-sided printing for printing (see the mark shown in FIG. 9). Pressure range Referring printing pressure ON timing by the press roller 21 in over emissions II).
In this way, a plate on which double-sided printing has been performed in which ink is filled corresponding to the backside plate-making image 8B in the divided plate-making master 8X on the plate cylinder 1 and a backside printed image is formed on the backside of the front surface printed paper 36a. The double-sided printed paper 36b for attachment is similar to the paper discharge operation of the single-sided printed paper 36c, and the plate cylinder 1 is blown by the air from the peeling claw 170 and the peeling fan 171 whose leading end approaches the outer peripheral surface of the plate cylinder 1. The double-side printed paper 36b that has been reliably peeled off from the upper divided master 8X is dropped downward and sent to the paper discharge conveying device 152, and rotated counterclockwise as shown in FIG. The sheet is discharged to the sheet discharge tray 172 while being attracted to the upper surface of the sheet discharge belt 158 by the suction force of the suction fan 159 and conveyed to the downstream side in the sheet conveyance direction X while being sucked and held. .
On the other hand, when the press cylinder 21 makes approximately three-quarters of a turn from the time when the press roller 21 contacts the outer peripheral surface of the plate cylinder 1 and the cam follower 241 contacts the large diameter peripheral surface of the cam plate 243C, an example of operation is performed. 1, the press roller 21 is returned to and held in the non-printing position away from the outer peripheral surface of the plate cylinder 1, and the plate cylinder 1 rotates to the home position again and stops. After the attaching operation, the double-sided stencil printing apparatus 300 enters a print standby state for the next regular double-sided printing.

  After the double-sided stencil printing apparatus 300 is in a print standby state, the printing conditions are input using the printing speed setting key 183 and various keys on the operation panel 173, and the position or density of the image is confirmed by trial printing as appropriate. When the print start key 175 is pressed after the number of prints is input through 179, the paper 36 is continuously fed from the paper supply unit 30, and the duplex printing operation for the set number of sheets set by the ten key 179 is performed.

The basic double-sided printing operation for the set number of sheets is basically different from the above-described printing operation, as described below. The other detailed operations are the above-described printing operation and the above-mentioned Patent Documents 7 to 7. Since those skilled in the art can easily understand and implement the double-sided printing operation disclosed in FIG.
First, the double-sided stencil printing apparatus 300 is configured to directly drive the respective units / apparatuses related to operations such as paper feeding, refeeding, front surface printing, back surface printing, and paper discharge. In other words, it is driven in accordance with the printing speed set in 183 or the automatically set standard printing speed.
Second, immediately after the belt drive motor 105 is set for each printing speed and driven to rotate at a specific rotation speed corresponding to the paper type according to a command from the control device 100 (CPU 101), the paper set for each printing speed is set. By temporarily stopping at a specific timing according to the type, that is, the conveyance belt 108 is set for each printing speed through the clockwise rotation of the rear 107 of the conveyance roller, and the surface is changed according to the conveyance speed according to the paper type The front end of the printed paper 36a is conveyed so as to come into contact with the stopper surface 53a. Immediately after the front end of the paper 36a comes into contact with the stopper surface 53a, the conveyance is stopped at a timing corresponding to the paper type set for each printing speed. As a result, the leading edge of the front surface printed paper 36a is bent by the energy when the front surface printed paper 36a contacts the stopper surface 53a. So they become minimum, the belt drive motor 105 and the like is that it is controlled.

Thirdly, in FIG. 4 and FIG. 9, when paper is printed on the second sheet corresponding to the surface plate-making image 8A in the divided plate-making master 8X on the plate cylinder 1, and subsequently, re-feeding is performed. When printing corresponding to the back side plate-making image 8B in the divided plate-making master 8X on the plate cylinder 1 on the back side of the first front-side printed paper 36a reversely conveyed by the means 45, a normal single-sided printing mode (operation example) As in (1), the printing pressure range variable means 28 is controlled so that the printing pressure ON timing by the press roller 21 in the printing pressure range pattern III shown in FIG. 9 is selected.
The detailed operation of the printing pressure range varying means 28 at this time is performed in the same manner as in the operation example 1 as described above. As shown in FIG. 4, the surface plate-making image in the divided plate-making master 8X on the plate cylinder 1 is obtained. The second sheet of paper is pressed against the 8A by the press roller 21, and continuously the press roller 21 occupies the printing position. The back surface of the first front surface printed paper 36 a that has been reversely conveyed by the paper refeeding unit 45 to 8B is pressed by the press roller 21.
Thereafter, for the set number N of sheets set with the numeric keypad 179, the same printing operation as described above is repeated until the (N-1) th sheet. When double-sided printing is performed on the back surface of the N-th (last first) front-side printed paper 36a that is temporarily held in the refeed conveyance device 104 immediately before the end of the printing operation, the mark shown in FIG. The printing pressure range variable means 28 is controlled so that the printing pressure ON timing by the press roller 21 in the pressure range pattern II is selected. That is, the back surface of the N-th surface printed paper 36a is pressed only by the press roller 21 only on the back plate making image 8B in the divided plate making master 8X on the plate cylinder 1, and the same paper discharge operation as described above is performed. After that, the double-sided printing operation for the set number N is completed, and the double-sided stencil printing apparatus 300 enters a print standby state.
As described above, in the normal regular duplex printing operation, the set number of duplex printings is performed every rotation of the plate cylinder 1, and the surface plate-making image of the divided plate-making master 8 </ b> X in almost half rotation of the plate cylinder 1. The front side printing corresponding to 8A is performed in this order in the order of the remaining half rotation of the plate cylinder 1 in the order of the back side plate making image 8B of the divided master making master 8X.
Fourthly, in the normal regular duplex printing operation, as compared with the duplex printing operation at the time of printing, as described above, the number of sheets 36 used for printing printing is not counted as the regular regular printing number. A point is mentioned.

According to the present embodiment, a sheet having a small thickness with respect to the sheet type is bent when it comes into contact with the stopper surface 53a of the refeed unit 45, and the resist deteriorates due to the deformation of the leading end of the sheet due to the bending. In order to prevent this, when the paper 36 is thin and light, the transport speed (linear speed) of the transport belt 108 is made slower than when the paper 36 is thick and heavy, and the stopper surface 53a of the surface-printed paper 36a is contacted. By making the stop timing of the conveying belt 108 after contact early, the deflection of the surface printed paper 36a after contacting the stopper surface 53a is minimized, and the surface printed paper after contacting the stopper surface 53a. By controlling the belt drive motor 105 so as to minimize the bending caused by the paper 36a being fed by the excessive feed of 36a, the tip of the paper 36a is controlled. The deformation parts is suppressed image misalignment without resist deterioration can be obtained a double-sided printed material is suppressed.
Moreover, according to this embodiment, it is possible to perform single-sided printing without using a useless master as well as the double-sided printing device (1) in Patent Documents 7 to 9 as well as exhibiting the advantages and effects described above. A new one-plate cylinder 1 pressing means both sides capable of producing a print with good image quality free of unevenness in print image density and difference in print image density at low cost and easily suppressing an increase in installation space. The present invention provides a one-step duplex printing apparatus using a printing method.

(Modification 1 of the first embodiment)
FIG. 15 shows a first modification of the first embodiment shown in FIGS.
The modified example 1 has an operation panel 173A from which the paper type setting key 186 constituting the paper type setting means arranged on the operation panel 173 is removed, and the paper type setting means (paper type setting key 186, enter key 180 and Instead of the four-way key 184), a difference is mainly that a paper thickness sensor 79 as a paper type detecting means is disposed at a predetermined portion shown in FIG. 1, as shown in FIG.
That is, the control device 100 (CPU 101) of the first modification changes the transport speed of the transport belt 108 of the refeed transport device 104 in accordance with the paper type related to the thickness of the paper 36 detected by the paper thickness sensor 79. It functions as a control means for controlling the belt drive motor 105 and controlling the belt drive motor 105 so that the conveyance stop timing of the conveyance belt 108 changes after the front end of the front surface printed paper 36a contacts the stopper surface 53a. Have.
The paper thickness sensor 79 is, for example, a type that measures the thickness of the paper 36 based on the transmittance of light transmitted through the paper 36, or a type that measures the reflected wave from the paper 36 using ultrasonic waves and measures the thickness of the paper 36. And a type of measuring the thickness of the paper 36 by measuring the distance to the surface of the paper 36 with laser light. Among these, the method using the light transmittance has been put into practical use and actually used. Yes.
The operation of the modification 1 can be easily implemented by those skilled in the art from the above-described configuration of the modification 1, the operation of the first embodiment, and the like.
According to the first modification, in addition to the advantage and effect that it is possible to save the trouble of manually setting the type of the paper 36 one by one, there are the same basic advantages and effects as in the first embodiment.

(Modification 2 of the first embodiment)
FIG. 15 shows a second modification of the first embodiment shown in FIGS.
In the modified example 2, in addition to the paper type setting means (paper type setting key 186, enter key 180, and 4-direction key 184) provided on the operation panel 173, the paper type detection means shown in FIG. The main difference is that the paper thickness sensor 79 is provided.
That is, the control device 100 (CPU 101) of the first modification changes the transport speed of the transport belt 108 of the refeed transport device 104 in accordance with the paper type related to the thickness of the paper 36 detected by the paper thickness sensor 79. It functions as a control means for controlling the belt drive motor 105 and controlling the belt drive motor 105 so that the conveyance stop timing of the conveyance belt 108 changes after the front end of the front surface printed paper 36a contacts the stopper surface 53a. Have.

In the second modification, for example, paper type setting means (paper type setting key 186, enter key 180, and four-direction key are used rather than a data signal relating to the thickness of the paper 36 transmitted / input from the paper thickness sensor 79 to the control device 100 (CPU 101) The control device 100 (CPU 101) can be configured in advance by giving a control function of giving priority to the data signal related to the thickness of the paper 36 selected and set in step 184).
The operation of Modification 2 can be easily implemented by those skilled in the art from the above-described configuration of Modification 2 and the operation of the first embodiment described above, and the description thereof will be omitted. The modification 2 also has the same basic advantages and effects as the first embodiment.

(Second Embodiment)
If the second embodiment does not require the remarkable advantages and effects as those of the first embodiment compared to the first embodiment shown in FIGS. From the function of the control device 100 (CPU 101) of the embodiment, the function of changing the conveyance stop timing of the conveyance belt 108 after the front-side printed sheet 36a abuts against the stopper member 53 according to the type of sheet is deleted. Thus, the configuration of a control device (not shown) may be used as a control unit having only a function of changing the conveyance speed of the conveyance belt 108 according to the type of paper.

In this case, a data table set for each printing speed of the paper type and the rotation speed of the belt drive motor 105 is stored in advance in the ROM of the control device (not shown).
Since the operation of the second embodiment can be easily implemented by those skilled in the art from the operation of the first embodiment described above, the description thereof is omitted. Moreover, since it can be easily implemented by those skilled in the art to apply Modification 1 or 2 to the second embodiment, the description thereof will be omitted.
(Third embodiment)
If the third embodiment does not require the remarkable advantages and effects as those of the first embodiment as compared with the first embodiment shown in FIGS. The function of changing the conveyance speed of the conveyance belt 108 of the refeed conveyance apparatus 104 according to the paper type is deleted from the function of the control device 100 (CPU 101) of the embodiment, and the surface printing is completed according to the paper type A control device (not shown) may be configured as a control unit having only a function of changing the conveyance stop timing of the conveyance belt 108 after the leading end of the sheet 36a contacts the stopper member 53.

In this case, the ROM of the control device (not shown) has a data table set for each printing speed including the paper type and the stop timing of the belt driving motor 105 after the front end of the front-side printed paper 36a contacts the stopper member 53. Is stored in advance.
Since the operation of the third embodiment can be easily implemented by those skilled in the art from the operation of the first embodiment described above, the description thereof is omitted. Moreover, since it can be easily implemented by those skilled in the art to apply the modification 1 or 2 to the third embodiment, the description thereof will be omitted.

The press roller rotation driving unit 54 shown in FIG. 2 is not an essential configuration as long as the above-described advantages are not desired. As shown, the press roller 21 may be in pressure contact with the plate cylinder 1 and driven to rotate.
As described above, the present invention has been described with respect to specific embodiments and modifications. However, the technical scope disclosed by the present invention is limited to those exemplified in the above-described embodiments and modifications. 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 partial cross section front view of the principal part of the double-sided stencil printing apparatus which shows the 1st Embodiment of this invention. FIG. 2 is a partial cross-sectional front view showing an enlarged configuration and operation around a printing unit, a refeed unit, and a printing pressure range variable unit of the double-sided stencil printing apparatus in FIG. 1. FIG. 2 is a partial cross-sectional front view showing an enlarged configuration and a surface printing operation around a printing unit, a refeed unit, and a printing pressure range variable unit of the double-sided stencil printing apparatus in FIG. 1. FIG. 2 is a partial cross-sectional front view showing an enlarged view of a configuration around a printing unit and a refeed unit of the double-sided stencil printing apparatus in FIG. 1 and an operation state in which a front end of a surface printed paper is in contact with a stopper member. FIG. 2 is a partial cross-sectional front view illustrating an enlarged double-sided printing operation in parallel with the configuration of the printing unit and the refeeding unit of the double-sided stencil printing apparatus in FIG. FIG. 5 is a top view of the refeeding unit (refeeding transport device, stopper member, refeeding registration roller) in FIG. 4 when viewed from the V4 direction. FIG. 2 is a partial sectional front view around a moving guide and moving means of the double-sided stencil printing apparatus in FIG. 1. FIG. 2 is a partial cross-sectional front view around a movement guide, a release cam, and a release pin of the double-sided stencil printing apparatus in FIG. 1. FIG. 3 is a diagram for developing and explaining three printing pressure range patterns applied corresponding to a divided master-making master on a plate cylinder used in the double-sided stencil printing apparatus in FIG. 1. FIG. 2 is a perspective view showing an arrangement example of a sheet feeding start light shielding plate and a resist start light shielding plate used in the double-sided stencil printing apparatus in FIG. 1 on an end plate of a plate cylinder. FIG. 2 is a front view of a main part showing a drive mechanism of a paper feed roller and a registration roller of a paper feed unit of the double-sided stencil printing apparatus in FIG. 1. It is a front view of the principal part of the image reading part of the double-sided stencil printing apparatus in FIG. It is a top view of the principal part of the operation panel of the double-sided stencil printing apparatus in FIG. It is a block diagram which shows the control structure of the principal part of the double-sided stencil printing apparatus in FIG. It is a block diagram which shows the control structure of the principal part of the double-sided stencil printing apparatus of the modifications 1 and 2.

Explanation of symbols

1 plate cylinder 8 master 8A front plate-making image 8B as first plate-making image back-side plate-making image 8C as second plate-making image 8 intermediate intermediate plate-making area 8X divided plate-making master 8Y plate-making master 8YA single-side plate-making image 11 as plate-making means Thermal head 15 Plate making part 16 Printing part 16a Nip part 17 Discharge part 18 Image reading part 19 Paper discharge part 21 Press roller (pressing means)
28 Printing Pressure Range Variable Means 30 Paper Feed Unit 36 Paper (Example of Sheet-like Recording Medium)
36a Front-side printed paper 36b Double-sided printed paper 36c Single-sided printed paper 45 Re-feeding means 46 Switching guide (switching means)
48 Refeed section 50 Roller guide plate (Refeed guide means / Refeed guide member)
51 Re-feeding registration roller (Refeeding registration means / Refeeding registration member)
52 Re-feed sensor (surface printed paper detection means)
53 Stopper member (refeed stop means / refeed stop member)
53a Stopper surface 79 Paper thickness sensor (paper type detection means)
81 Movement guide (paper clamping means)
81b Clamp claw (clamping member)
87 Moving means 100 Control device 101 CPU as control means
102 ROM
104 Re-feed transport device (re-feed transport means)
173, 173A Operation panel 180 Enter key (paper type setting means)
184 Four-way key (paper type setting means)
186 Paper type setting key (paper type setting means)
300 Double-sided stencil printing apparatus X as an example of double-sided printing apparatus X Paper transport direction X1 Master transport direction Y Paper width direction

Claims (7)

Relative to a plate cylinder on which a plate-making master for double-sided printing in which two first plate-making images and second plate-making images are formed side by side along the rotation direction of the plate cylinder, and the plate cylinder A printing unit having pressing means that can be freely contacted and separated, a paper discharge unit that discharges paper printed in the printing unit, and a surface of the printing unit corresponding to the first plate-making image or the second plate-making image. A paper re-feeding means for temporarily holding the surface-printed paper on which the printed image is formed, transporting the paper toward the pressing means, inverting the paper by the pressing means, and re-feeding the printing unit; In a double-sided printing apparatus comprising a switching unit that guides the paper that has passed through the printing unit to the refeed unit or the paper discharge unit,
The refeed unit includes a refeed conveyance unit that temporarily holds a surface printed sheet and conveys the sheet toward the pressing unit, and a front end of the surface printed sheet conveyed by the refeed conveyance unit. Refeed stop means for temporarily stopping before delivering to the pressing means,
A double-sided printing apparatus comprising: a control unit that changes a conveyance speed of the re-feed conveyance unit according to the type of paper. Relative to a plate cylinder on which a plate-making master for double-sided printing in which two first plate-making images and second plate-making images are formed side by side along the rotation direction of the plate cylinder, and the plate cylinder A printing unit having pressing means that can be freely contacted and separated, a paper discharge unit that discharges paper printed in the printing unit, and a surface of the printing unit corresponding to the first plate-making image or the second plate-making image. A paper re-feeding means for temporarily holding the surface-printed paper on which the printed image is formed, transporting the paper toward the pressing means, inverting the paper by the pressing means, and re-feeding the printing unit; In a double-sided printing apparatus comprising a switching unit that guides the paper that has passed through the printing unit to the refeed unit or the paper discharge unit,
The refeed unit includes a refeed conveyance unit that temporarily holds a surface printed sheet and conveys the sheet toward the pressing unit, and a front end of the surface printed sheet conveyed by the refeed conveyance unit. Refeed stop means for temporarily stopping before delivering to the pressing means,
A double-sided printing apparatus comprising: a control unit that changes a conveyance stop timing of the re-feed conveyance unit after the front end of the front-side printed sheet contacts the re-feed stop unit according to a type of the sheet . Relative to a plate cylinder on which a plate-making master for double-sided printing in which two first plate-making images and second plate-making images are formed side by side along the rotation direction of the plate cylinder, and the plate cylinder A printing unit having pressing means that can be freely contacted and separated, a paper discharge unit that discharges paper printed in the printing unit, and a surface of the printing unit corresponding to the first plate-making image or the second plate-making image. A paper re-feeding means for temporarily holding the surface-printed paper on which the printed image is formed, transporting the paper toward the pressing means, inverting the paper by the pressing means, and re-feeding the printing unit; In a double-sided printing apparatus comprising a switching unit that guides the paper that has passed through the printing unit to the refeed unit or the paper discharge unit,
The refeed unit includes a refeed conveyance unit that temporarily holds a surface printed sheet and conveys the sheet toward the pressing unit, and a front end of the surface printed sheet conveyed by the refeed conveyance unit. Refeed stop means for temporarily stopping before delivering to the pressing means,
Depending on the type of paper, the conveyance speed of the re-feed conveyance means is changed, and the conveyance stop timing of the re-feed conveyance means after the front end of the surface printed paper comes into contact with the re-feed stop means is set. A double-sided printing apparatus having a control means for changing. The double-sided printing apparatus according to claim 1, 2, or 3,
The double-sided printing apparatus, wherein the paper type is set according to at least one of the thickness and strength of the paper. The double-sided printing apparatus according to any one of claims 1 to 4,
A double-sided printing apparatus comprising a paper type setting means for setting the paper type. The double-sided printing apparatus according to any one of claims 1 to 5,
A double-sided printing apparatus comprising: a paper type detecting unit that detects the paper type. The double-sided printing apparatus according to any one of claims 1 to 6,
The surface-printed paper, which is disposed near the re-feed stop means and is temporarily stopped by the re-feed stop means, is released at a predetermined timing to cause the press means to press the front-printed paper. A double-sided printing apparatus comprising a re-feeding resist means for contacting with the sheet.

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