JP5059342B2 - Duplex printing device - Google Patents

Description

  The present invention relates to a duplex printing apparatus, and more particularly to a duplex printing apparatus capable of switching between single-sided printing using a plate-made master and one-step duplex printing using a divided master-made master.

  Conventionally, digital thermal stencil printing is known as a simple printing method. The stencil printing apparatus used for this stencil printing has a master in accordance with image information by bringing a thermal head in which fine heating elements are arranged in a line into contact with the master and conveying the master while energizing the heating elements in pulses. After the master is wound around the outer peripheral surface of a porous cylindrical plate cylinder, the outer surface of the plate cylinder is pressed by a pressing means such as a press roller through a sheet of paper, so that the ink is transferred from the master perforated portion. Is transmitted, and this is transferred to a sheet to obtain a printed image.

  In this stencil printing, in recent years, double-sided printing, in which printing is performed on both sides of a sheet, has been frequently performed for the purpose of reducing paper consumption and document storage space. Conventionally, in this double-sided printing, the paper stacked on the paper feeding unit is passed through the printing unit, printed on one side, then turned over, and again passed through the printing unit to print on the other side. However, there is a problem in that it is troublesome to set the paper once ejected to the paper feeding unit or to align the paper after single-sided printing. In addition, since the paper is passed through the printing unit twice, the net printing time is twice as long as that of single-sided printing, and it takes too much time.

  In order to solve the above-mentioned problems, a divided pre-printed master in which two first and second pre-made images are arranged in the rotation direction of the plate cylinder is used, and the first sheet is fed from the paper feeding unit. After one of the plate-making images is printed on the surface, the sheet is guided to the auxiliary tray, the second sheet is fed from the paper feeding unit, and one of the plate-making images is printed on the surface. The paper is guided to the auxiliary tray, and the first sheet is re-feeded from the auxiliary tray, and the other plate-making image is printed on the back surface of the paper, and the paper is discharged to the paper discharge tray. For example, “Patent Document 1” discloses a double-sided printing apparatus that obtains a double-sided printed matter in one step by continuously performing the operation.

JP 2003-200355 A

  By the way, in the double-sided printing apparatus which obtains a double-sided printed matter by the above-mentioned 1 process, printing is stopped in the middle of the printing in double-sided printing mode, and the plate cylinder (double-sided plate making or single-sided plate-making master) which was printing is wound There is a case where printing is resumed by replacing the plate cylinder) with another plate cylinder (a plate cylinder on which a double-side plate-making or a single-side plate-making master is wound).

  In this case, when the conventional double-sided printing apparatus performs printing with a plate cylinder on which a master made by double-side plate making is wound, and the printing cylinder is replaced by interrupting printing halfway, the plate cylinder after the replacement is a single-side plate making or double-side plate making. Regardless of which one of the masters was wound, printing could not be resumed unless the operations of plate making, printing, and printing were repeated again. For this reason, even if the plate cylinder for winding the master for double-sided plate making is replaced with the plate cylinder for winding the master for double-sided plate making, the trouble of performing plate making again has occurred. Note that single-sided printing was possible when the paper on the paper feed tray was larger than the master for double-sided platemaking after replacement.

  Furthermore, the master wound around the plate cylinder before and after the replacement may have been made in the single-side plate making mode, or may have been made in the double-side plate making mode. For this reason, for example, when printing is stopped while a single-sided printing master is wound on a single-sided printing cylinder, and printing is stopped and replaced with a double-sided printing master that winds up a single-sided printing master, It is conceivable that the print instruction in the single-sided printing mode is erroneously performed using the sheet as it is.

Furthermore, when double-sided printing is being performed by the plate cylinder on which the double-sided master is wound, if printing is stopped and replaced with a plate cylinder on which the single-sided master is wound, the paper remains as it was during double-sided printing. A case where a print instruction is issued in the double-sided printing mode is considered.
It is assumed that printing is stopped in the middle of printing in this way, and the printing mode is erroneously instructed after the plate cylinder is replaced.

  At this time, the paper size is changed in a smaller direction after the plate making, for example, when the single-sided printing is performed with the paper smaller than the plate making area of the divided plate making master after the plate making for double-sided printing is performed, or after the plate making When the plate cylinder is replaced and the plate making area of the pre-printed master or the divided pre-made master wound around the new plate cylinder is larger than the paper to be used, etc. It will be in direct contact with the pre-printed master on the outer peripheral surface of the cylinder. In such a case, the ink supplied from the inside of the plate cylinder is directly transferred to the surface of the pressing means, and it becomes very difficult to remove the ink that has entered the valleys of the protrusions on the pressing means surface. There is a problem of wasting paper and ink supplies due to mistakes.

  The present invention has been made paying attention to the above-mentioned problems, and after interrupting printing on a plate cylinder around which a master for double-side plate making is interrupted, unnecessary master replacement can be prevented when resuming printing. It is an object of the present invention to provide a double-sided printing apparatus capable of accurately performing a display capable of preventing printing in an incorrect printing mode when printing is resumed after replacing the printer.

The invention described in claim 1 has a plate cylinder and pressing means provided so as to be able to contact with and separate from the plate cylinder, and the first plate-making image and the second plate-making image in the length direction of the master during double-sided printing. In the double-sided printing apparatus capable of switching between double-sided printing and single-sided printing in which the backside printing process is performed after the surface printing process is performed by winding the divided master-making master having A master detecting means for detecting the rear end of either the pre-made master or the divided pre-made master that is wound around the plate, and is wound around the plate cylinder based on detection information from the master detecting means. Control means for discriminating the type of the master, and based on the information that the plate making in at least one of the double-sided printing mode and the single-sided printing mode has been performed, the plate making mode at that time is stored in the storage device, and stored in the storage device. Above If it has a surface plate making that have been stored, the type of the plate cylinder is on the same plate cylinder to be exchanged master is detected by the master detector, platemaking master on the plate cylinder in the duplex printing mode If it has been done, printing restart is allowed, otherwise printing restart is disabled .

According to a second aspect of the present invention, in the double-sided printing apparatus according to the first aspect, a display control means for displaying the master state on the operation panel, and a main body for transmitting a recognition signal of the plate cylinder to the control means when the connection state is established A side contact row, a plate cylinder side contact row, and a detecting means capable of detecting insertion / removal to a plate cylinder mounting portion for mounting the plate cylinder on the apparatus main body from an intermittent state of the main body side contact row and the plate cylinder side contact row. The plate cylinder of the double-sided plate making to wind the master made in the above-mentioned double-sided printing mode when it is in the middle of printing or is waiting in a normal state that can be printed is re-inserted into the plate cylinder mounting portion When detected by the detection means capable of detecting the insertion / extraction and the master detection means , the display control means displays on the operation panel that printing on the plate cylinder of the double-side plate making can be resumed.

According to a third aspect of the invention, the double-sided double-sided printing apparatus according to claim 2, the detection means and the master detection means can detect the insertion and removal when printing stops due to an error processing according to the error signal during printing When it is detected that the double-sided plate cylinder that winds the master made in printing mode is inserted again, it is assumed that the same plate cylinder has been inserted and removed, and the same printing as before stopping is resumed. It is characterized by.

The invention according to claim 4 is the double-sided printing apparatus according to claim 2 ,
When the printing cylinder is stopped in the middle of printing or waiting in a normal state where printing is possible, the plate cylinder is replaced and the type of master on the printing cylinder is detected by the master detection means , and the detected plate cylinder is detected . Printing is permitted only when the master plate-making mode and the plate-making mode written in the storage device are both-side plate-making. In other cases, the display control means displays that printing cannot be resumed. It is characterized by.

  According to a fifth aspect of the present invention, in the double-sided printing apparatus according to the fourth aspect, when the printing can be resumed after the plate cylinder replacement, the display control means prints in the plate making mode before stopping or waiting on the operation panel. Is displayed as being resumable.

According to a sixth aspect of the present invention, in the double-sided printing apparatus according to the fourth aspect, when the resumption of printing is not permitted after the plate cylinder replacement, the display control means cannot perform resumption of printing on the operation panel and needs to make a plate again. This is characterized in that a message is displayed and a state is waited for the input of another plate making instruction.

According to the invention of claim 1 of the present application, when the storage device stores the fact that the double-sided master is wound around the plate cylinder, the drum that winds the double-sided master is replaced with another drum. is Do, the master type master on the other drum is detected by the master discriminating means, the master is allowed to resume printing if it is those prepress double-sided printing mode, which is double-sided plate-making in the storage device Is not stored, it is considered that it is necessary to make the plate again, and printing cannot be resumed. Therefore, it is not necessary to waste supplies of ink, paper, etc. due to a printing mistake, and an unnecessary master The detection operation of the discrimination means can be eliminated, and control can be simplified and energy can be saved.

According to the second aspect of the present invention, the fact that the double-sided plate-making drum has been changed from the double-sided plate-making drum to the double-sided plate-making drum after printing is stopped or in standby is detected by the plate cylinder recognition signal and the detecting means capable of detecting the insertion and removal of the drum. Since it is possible to display on the operation panel that printing can be resumed with the double-sided plate-making drum, it is possible to prevent the plate-making from being performed again, and the master is not consumed wastefully. In addition, it is possible to reduce time loss and power consumption due to plate making again.

According to the invention of claim 3 of the present application, after an error is displayed on the operation panel in response to an error signal due to a paper jam or the like during printing, the plate cylinder is detected by the plate cylinder recognition signal and the detection means capable of detecting the insertion and removal of the plate cylinder. If it is inserted again, it can be recognized that the plate cylinder has not been replaced, and printing is resumed in the same way as before stopping, so that the master is not consumed wastefully without making the plate again. In addition, it is possible to eliminate the display of whether or not printing can be resumed, and it is possible to eliminate the troublesomeness of displaying on the operation panel that printing can be resumed each time the drum is inserted or removed.

According to the invention of claim 4 of the present application, after the user temporarily stops printing on the drum subjected to double-side plate making, when another drum is replaced, the state of the master on the other drum is detected, and this is stored in the storage device. written by If you previously had been confirmed to be the same as the double-sided plate-making mode double-sided printing restart is allowed, display the print can not function unless it is a plate-making again if it other than the master has been replaced with a wound drum Displayed by the control means, it is possible to prompt plate making again.

  According to the invention of claim 5 of the present application, only when each plate making mode before and after the drum replacement is a master of both sides plate making mode, the operation panel displays that printing can be resumed. If you want to print with, you can inform that double-sided printing can be resumed.

  According to the sixth aspect of the present invention, when the exchanged drum is other than the double-side plate making, it is displayed on the operation panel that printing cannot be resumed on the operation panel, and then printing cannot be resumed even if the print button is pressed. Thus, it is not necessary to waste a supply due to a printing mistake. After that, the user recognizes it, returns to the initial state again, and presses the plate-making button to enable proper printing. Furthermore, in the case where the replaced drum is a master that has been subjected to separate plate making other than double-side plate making, it is possible to prevent the occurrence of a problem that the surface of the pressing means is soiled with ink by directly pressing the perforated portion with the pressing means. it can.

  FIG. 1 shows a duplex printing apparatus employing a first embodiment of the present invention. In FIG. 1, a duplex printing apparatus 1 includes a printing unit 2, a plate making unit 3, a paper feeding unit 4, a plate discharging unit 5, a paper discharging unit 6, an image reading unit 7, an auxiliary tray 8, a refeed unit 9, a switching member 10, and the like. With these, the single-sided printing using a single-sided printing master (plate-making master) 66, which will be described later, and the one-step double-sided printing using the double-sided printing master (divided plate-making master) 65 are switchable. Has been.

  The printing unit 2 is disposed substantially at the center of the apparatus main body 11 of the double-sided printing apparatus, and includes a plate cylinder 12 serving as a printing drum and a press roller 13 serving as pressing means. The plate cylinder 12 includes a pair of flanges (not shown) that are rotatably supported by a support shaft 14 that also serves as an ink supply pipe, a porous support plate (not shown) wound around the outer peripheral surface of each flange, and a porosity (not shown). It is mainly composed of a mesh screen (not shown) wound around the outer peripheral surface of the support plate. The plate cylinder 12 is configured to be rotationally driven by a plate cylinder driving unit 121 (see FIG. 6) and to be detachable from the apparatus main body 11.

Here, a connecting mechanism including a plate cylinder unit 162 including the plate cylinder 12 in the printing unit 2 and plate cylinder receiving frames 172 and 173 before and after mounting the plate cylinder unit 162 in the apparatus main body 11 will be described. The plate cylinder unit 162 is integrated as a unit with the plate cylinder 12 and an ink pack 197 and a pump 196 described later, and can be attached to and detached from the apparatus main body 11 by a simple operation.
In this embodiment, as shown in FIG. 4B, the plate cylinder 12 has a size of an outer peripheral surface capable of obtaining a printed product of A3 size at the maximum during single-sided printing.

  An ink supply means 15 is disposed inside the plate cylinder 12. The ink supply means 15 includes a support shaft 14, an ink roller 16, and a doctor roller 17. The ink supplied from the support shaft 14 has a wedge-shaped cross section formed in a proximity portion between the ink roller 16 and the doctor roller 17. Ink is supplied to the inner peripheral surface of the plate cylinder 12 from the ink reservoir 18 formed by collecting in the space. A stage portion is formed on the outer peripheral surface of the plate cylinder 12, and a clamper 19 for holding the tip of the master is disposed on the outer peripheral surface of the plate cylinder 12. The clamper 19 is opened and closed by an opening / closing means (not shown) when the plate cylinder 12 is rotated to a predetermined position.

  The plate cylinder 12 is driven to rotate clockwise by the printing drum driving means 16d shown in FIG. The plate cylinder 12 is pivotally supported by the support shaft 14 via front and rear flange portions 201 and 202. A gear 181 is integrally coupled to the rear flange portion 202. The gear 181 meshes with a small gear 183 that is rotationally driven by a motor 182. A motor 182 for driving the plate cylinder 12 is a stepping motor, and can accurately rotate the plate cylinder 12 about the spindle 14 in accordance with the number of pulses.

As shown in FIG. 7, a plate cylinder unit 162 is formed by a plate cylinder 12 and a plate cylinder support frame 161 pivotally supported so as to cover the plate cylinder and equipped with a plurality of attachment members to be described later. The plate cylinder unit 162 is detachably attached to the front and rear plate cylinder receiving frames 172 and 173 by opening the door cover 120 of the apparatus main body 11.
A door cover open / close detection sensor 210 (see FIG. 6) is provided near the opening edge of the apparatus main body 11 that is closed by the door cover 120. When the door cover 120 is held in the closed state, an off signal is generated. An ON signal is input to the control means 160 when the door is opened.

  The plate cylinder support frame 161 has a substantially plate-like main portion 163 that covers the upper portion of the plate cylinder 12 along the plate cylinder longitudinal direction X, and bends and extends downward from the front and rear ends of the main portion 163 to extend the front and rear ends of the plate cylinder 12. Front and rear end plate portions 164 and 165 (see FIG. 8), a folding handle 166 attached to the approximate center of the main portion 163 for facilitating conveyance outside the apparatus body 11, and front and rear ends A long frame member 166 having a long frame shape is provided at both lower ends of the plate portions 164 and 165 and is located on the paper discharge side of the plate cylinder 12 and connects both end portions to each other.

Next, the front and rear plate cylinder receiving frames 172 and 173 which are plate cylinder mounting portions on which the plate cylinder support frame 161 is placed will be described.
As shown in FIG. 8A, the front plate cylinder receiving frame 172 has a horizontally long plate-like shape in which a fitting recess 721 and left and right left and right engaging portions 722 and 723 are formed on the upward surface. The fitting recess 721 has a shape in which the front end plate portion 164 of the plate cylinder support frame 161 is fitted, and the left and right locking portions 722 and 723 are locked at portions facing the side edges of the front end plate portion 164. A hole h1 is formed. The front locking means 174 is mounted by the locking hole h1 and the pins 175 on the left and right locking portions 722 and 723 side. The front locking means 174 has a symmetrical structure, a pin hole h2 formed in the inward wall of the left and right engaging portions 722 and 723, and a pin 175 engaged so as to be able to enter the pin hole h2. And a spring 177 which is coupled to the rear end of the pin 175 and protrudes and biases the pin.

Here, the facing interval between the left and right engaging portions 722 and 723 is formed slightly larger than the lateral width of the front end plate portion 164, and when the front end plate portion 64 is fitted, the left and right engaging portions 722, 722, Each pin 75 of 723 enters and the plate cylinder support frame 161 can be locked in the fitting recess 721.
As shown in FIG. 8B, the rear plate cylinder receiving frame 173 has a vertically-oriented bent plate shape and is integrally coupled to the inside of the apparatus main body 11. The rear plate cylinder receiving frame 173 that forms the plate cylinder mounting portion includes a vertical wall portion 731, a locking bent portion 732 on the lower edge side on which the lower edge 651 of the rear end plate portion 165 is placed, and a locking bending portion The lower projection 733 that is integrally coupled to the portion 732 and the vertical wall portion 731 and that engages with the lower notch 652 of the rear end plate portion 165, and the alignment at which the end portion 141 of the support shaft 14 that is formed on the vertical wall portion 731 is inserted. A hole 734 and an upper protrusion 735 that is integrally coupled to the vertical wall portion 731 and into which the upper alignment hole 653 of the rear end plate portion 165 is fitted. Here, the lower notch 652 engages with the locking bent portion 732 of the rear plate cylinder receiving frame 73, the rear end 801 of the plate cylinder shaft is fitted into the alignment hole 734, and the upper alignment hole is formed in the upper protrusion 735. By fitting 653, the rear end plate portion 165 is aligned and fitted to the rear plate cylinder receiving frame 173. Further, the front end plate portion 164 is fitted into the fitting recess 721 and locked by the left and right front locking means 174 of the left and right engaging portions 722 and 723, so that the plate cylinder 12 of the plate cylinder unit 162 is appropriately operated. It is mounted so that it can be removed without being displaced.

As shown in FIG. 8, a main body side contact row J1 on the signal line connected to the control means 160 is attached to the lower wall side of the fitting recess 721 of the front plate cylinder receiving frame 172 constituting the plate cylinder mounting portion. A plate cylinder side contact row J2 is formed on the lower surface of the lower end of the front end plate portion 164 on the plate cylinder unit 162 side in contact with the fitting recess 721, and these can detect the insertion and removal of the plate cylinder 12 into the plate cylinder mounting portion. The connection detection means 220 is comprised.
In a state where the plate cylinder unit 162 is locked in the fitting recess 721, the main body side contact row J1 of the fitting recess 721 and the plate cylinder side contact row J2 of the front end plate portion 164 can be connected. A signal line on the plate cylinder unit 162 side is connected.

  As shown in FIG. 7, a front handle 641 for attaching and detaching the plate cylinder unit 162 is attached to the front end plate portion 164 of the plate cylinder support frame 161. In addition, an ink pack 197 and a dip switch 185 for manually setting the type of the wound master are mounted on the lower side thereof, and these are connected to the plate cylinder side contact row J2 via signal lines. The dip switch 185 is configured so that a double-sided printing master and a single-sided printing master can be set manually.

As shown in FIG. 7, the front end of the support shaft 14 is fixed to the front end plate portion 164. The support shaft 14 has an ink supply path ri formed continuously over a portion facing the inside of the plate cylinder 12 and a portion facing the front end plate portion 164, and a plurality of holes (not fixed) arranged in the longitudinal direction X in the plate cylinder 12. Ink supply can be performed as shown in FIG. The ink supply path ri is connected to a discharge pipe 961 of an ink supply pump 196 attached to the front end plate portion 164 side. When driven, the pump 196 is configured to suck ink from an ink pack 197 placed on the ink base 199 side and supply the ink into the plate cylinder 12 through an ink supply path.
The pump 196 can be driven in accordance with a drive signal from the ink amount detection adjustment unit 133 (see FIG. 6) on the control unit 160 side. The ink amount detection adjusting means 133 controls the driving of the pump 196 when the ink amount falls below an appropriate amount according to an ink amount signal of an ink detection sensor (not shown) provided in the drum.

  A press roller 13 is disposed below the plate cylinder 12. The press roller 13 is configured by winding an elastic body such as rubber around a metal core 13 a and is provided so as to extend in the axial direction of the plate cylinder 12. As shown in FIG. 2, the press roller 13 is rotatably supported by a pair of arm members 20 serving as press roller support members at both ends of the core portion 13a. Each arm member 20 having a substantially L shape is integrated by a swing shaft 21 attached to a portion near the bent portion, and the swing shaft 21 is rotatably supported by the apparatus main body 11. Yes. Between each arm member 20, in addition to the press roller 13, a refeed guide member 22, a refeed resist roller 23 as a refeed resist member, a refeed positioning member 24, a refeed transport member 25, a cleaning A cleaning roller 26 and a guide plate 27 are provided as members.

  As shown in FIG. 2, the refeed guide member 22 disposed in the vicinity of the right side of the press roller 13 is integrally provided on each of the support shafts 28a, 29a, and 30a, and the respective peripheral surfaces thereof are pressed by the press roller. A plurality of roller rollers 28, 29, 30 pressed against the peripheral surface of the paper 13, and a paper guide plate 31 formed in a curved shape for causing the paper P as a printing paper to follow the peripheral surface of the press roller 13; have. Each support shaft 28a, 29a, 30a is rotatably supported at each end by each arm member 20, and is urged toward the core portion 13a by urging means (not shown). Each of the rollers 28, 29, and 30 is integrally attached to the corresponding support shaft 28 a, 29 a, 30 a with a predetermined interval over substantially the entire width of the press roller 13. The paper guide plate 31 is disposed at a position away from the peripheral surface of the press roller 13 by a predetermined distance that is smaller than the radius of each of the rollers 28, 29, 30, and both ends thereof are fixed to the arm members 20. Has been. The paper guide plate 31 is formed to have a curved surface centered on the core portion 13 a, and the paper guide plate 31 is configured to bring the peripheral surfaces of the rollers 28, 29, and 30 into contact with the peripheral surface of the press roller 13. A plurality of openings are formed.

  A re-feeding registration roller 23 is disposed below the press roller 13. The roller-shaped refeed resist roller 23 is rotatably supported by a support shaft 23a, and the support shaft 23a is attached to one end of a swing arm 32 as a refeed resist support member. The swinging arm 32 having a substantially square shape is supported by a support shaft 32a fixed between the arm members 20 so that the bent portion can swing freely. It is determined so that it is located at the approximate center in the width direction of the press roller 13 and is located in the middle of the position where each roller 30 is disposed. At the other end of the swing arm 32, a plunger 33a of a solenoid 33 attached to one arm member 20 via a bracket (not shown) and one end are fixed to the one arm member 20 and supported with respect to the swing arm 32. The other end of the tension spring 34 is attached to the shaft 32a to give a rotational biasing force in the counterclockwise direction in FIG. With this configuration, the re-feeding registration roller 23 occupies the press contact position indicated by the solid line in FIG. 2, which presses the peripheral surface against the peripheral surface of the press roller 13 with a predetermined press contact force when the solenoid 33 is operated. When the operation is released, the peripheral surface of the tension spring 34 is separated from the peripheral surface of the press roller 13 by the urging force of the tension spring 34 and occupies a separation position indicated by a two-dot chain line in FIG. The re-feeding resist contact / separation mechanism 40 is constituted by the solenoid 33 and the tension spring 34.

A refeed positioning member 24 is disposed near the upper portion of the refeed resist roller 23. The refeed positioning member 24 is made of a plate material having an L-shaped cross section, and is formed so that the width thereof is substantially the same as the width of the press roller 13, and the bent end portion 24 a faces upward. The portion is fixed to each arm member 20. The refeed positioning member 24 has a notch (not shown) for preventing the refeed registration roller 23 from colliding with the swing.
A refeed conveyance member 25 is disposed below the press roller 13 and to the left of the refeed positioning member 24. The refeed conveyance member 25 includes a conveyance member main body 35, a driving roller 36, a driven roller 37, an endless belt 38, a suction fan 39, and the like, and an auxiliary tray 8 is integrally formed on the upper surface thereof.

The transport member body 35, which is a casing formed so that its upper surface is opened and its width is slightly smaller than the interval between the arm members 20, is provided with bearings (not shown) on both the upstream and downstream sides of the sheet transport direction. Each bearing (not shown) rotatably supports the drive shaft 36a and the driven shaft 37a. Both ends of the drive shaft 36a penetrate both side surfaces of the conveying member main body 35, and both the penetrated both end portions are rotatably supported by a bearing member (not shown) provided in the apparatus main body 11. A drive gear (not shown) is attached to one end of the drive shaft 36 a, and the drive shaft 36 a is rotationally driven by a conveying member drive motor 122 provided in the apparatus main body 11. The driven shaft 37a is configured such that both ends thereof do not penetrate both side surfaces of the conveying member main body 35. Bosses 35a are integrally provided on both outer sides of the upstream end of the conveying member body 35 in the sheet conveying direction, and each boss 35a is fitted in a long hole (not shown) formed in each arm member 20, respectively. Has been. With this configuration, the transport member main body 35 is centered on the drive shaft 36a as the arm members 20 swing when the press roller 13 is brought into and out of contact with the plate cylinder 12 by a press roller contact / separation mechanism 55 described later. Rocking is possible.
The plurality of roller-shaped drive rollers 36 are integrally attached to the drive shaft 36a, and a predetermined interval is provided between the drive rollers 36. A plurality of driven rollers 37 having the same shape as the driving roller 36 are integrally attached to the driven shaft 37 a at the same interval as each driving roller 36. An endless belt 38 having a plurality of holes (not shown) is stretched between the drive rollers 36 and the corresponding driven rollers 37 corresponding thereto with a predetermined tension. The endless belt 38 made of a friction resistance member is moved in the direction indicated by the arrow in FIG. 2 when the drive shaft 36a is rotationally driven by the conveying member drive motor 122.

  A suction fan 39 is integrally attached to the lower surface of the conveying member main body 35, and the auxiliary tray 8 is integrally attached to the upper surface of the conveying member main body 35. The auxiliary tray 8 has a plurality of openings (not shown) for allowing the endless belts 38 to face the sheet conveying surface, and a fence for receiving the conveyed sheet P at the downstream end in the sheet conveying direction. 8a is integrally formed. A hole (not shown) is provided on the lower surface of the conveying member main body 35, which is a mounting surface of the suction fan 39, and the suction fan 39 is activated thereby to apply a negative pressure to the inside of the conveying member main body 35, which is a casing. The sheet P is sucked onto the upper surface of each endless belt 38 that is generated and moved. The suction force of the suction fan 39 and the frictional resistance of the endless belt 38 are determined between the sheet P and each endless belt 38 when the leading end of the sheet P comes into contact with the bent end 24a of the refeed positioning member 24. The strength is set so that slipping occurs. The refeeding guide member 22, the refeeding registration roller 23, the refeeding positioning member 24, and the refeeding conveyance member 25 constitute a refeeding unit 9.

  A cleaning roller 26 that cleans the peripheral surface of the press roller 13 is disposed near the press roller 13 and above the refeed conveyance member 25. The cleaning roller 26 having substantially the same width as that of the press roller 13 has at least a surface made of a highly hygroscopic material such as Japanese paper or sponge, and has a core portion 26a integrally at the center thereof. . The cleaning roller 26 is rotatably supported by fitting the core portion 26a into a long hole (not shown) formed in each arm member 20, and a press roller by a biasing means (not shown) provided in the long hole. The peripheral surface is constantly pressed against the peripheral surface of the press roller 13 with a predetermined pressing force. The cleaning roller 26 is about one-tenth of the peripheral speed of the press roller 13 in the same direction as the press roller 13 when the press roller 13 rotates by a cleaning roller driving means (not shown) provided on one arm member 20. It is rotationally driven at a peripheral speed.

A guide plate 27 is disposed on the upper left side of the cleaning roller 26. Both ends of the guide plate 27, which is a plate material, are fixed to each arm member 20. The sheet P pressed against the plate cylinder 12 by the press roller 13 does not touch the cleaning roller 26 and is attached to the auxiliary tray 8. Guide you to head. The guide plate 27 is disposed at a position close to the peripheral surfaces of the press roller 13 and the cleaning roller 26.
On the other end side of each arm member 20 opposite to the one end side where the press roller 13 is supported, rotatable cam followers 41 are arranged in such a manner as to face each other. Further, the other end of the printing spring 42 having one end fixed to the apparatus main body 11 is attached in the vicinity of the position where the cam follower 41 of each arm member 20 is disposed. As a result, each arm member 20 is given a rotational biasing force in the clockwise direction in the drawing around the swing shaft 21.

  In the vicinity of the left side of each cam follower 41, a multistage cam 43 having three cam plates 43A, 43B, 43C is disposed. Each cam plate 43A, 43B, 43C is fixed to a cam shaft 44 supported at both ends by the apparatus main body 11 and movably in the direction perpendicular to the paper surface of FIG. The cam plate 43B, the cam plate 43A, and the cam plate 43C are arranged in this order. Each of the cam plates 43A, 43B, and 43C has a base portion that is a disc concentric with the cam shaft 44 and a convex portion having the same protruding amount. As shown in FIG. 3, the multistage cam 43 is provided with plate cylinder driving means via a drive gear 45 attached to the cam shaft 44 and a transmission gear 47 attached to a support shaft 46 rotatably supported by the apparatus main body 11. The rotational force from 121 is transmitted, and it is rotated in the clockwise direction in FIG.

  The press roller 13 occupies a separation position shown in FIG. 2 in which the circumferential surface is separated from the circumferential surface of the plate cylinder 12 when any convex portion of each of the cam plates 43A, 43B, and 43C comes into contact with the cam follower 41. When the contact between any of the convex portions and the cam follower 41 is released, the peripheral surface occupies the press contact position shown in FIG. 3 where the peripheral surface presses the peripheral surface of the plate cylinder 12 by the urging force of the printing pressure spring 42. Each of the cam plates 43A, 43B, and 43C is configured so that the base and the cam follower 41 do not come into contact when the press roller 13 occupies the press contact position. The shape of the convex portions of the cam plates 43A, 43B, and 43C is such that the contact range between the press roller 13 and the plate cylinder 12 is a range in which all of the front surface region, the intermediate region, and the back surface region shown in FIG. Thus, the cam plate 43B is formed so as to be in the same range as the surface region, and the cam plate 43C is formed so as to be in the combined range of the downstream portion of the surface region, the intermediate region, and the back surface region. The intervals between the cam plates 43A, 43B, 43C are set to be sufficiently larger than the plate thickness of the arm member 20.

  In FIG. 2, press roller locking means (not shown) that prohibits the swinging of each arm member 20 in a state where the press roller 13 occupies the separated position is disposed near the right side of each arm member 20. A press roller locking means (not shown) has a solenoid (not shown), and a state of holding each arm member 20 and a state of releasing the holding are selectively switched by switching on / off of the solenoid (not shown). A solenoid (not shown) is operated in a state where the cam follower 41 is in contact with any one of the convex portions of the cam plates 43A, 43B, and 43C.

A moving arm 48 and a step cam 49 are disposed near the lower portion of the cam shaft 44 as shown in FIG. The moving arm 48 having a substantially L-shape has a bent portion attached to a support shaft 48a rotatably supported by the apparatus main body 11. A roller 48b is provided at one end of the moving arm 48, and the other end is provided at the other end. Each cam follower 48c is rotatably attached. Furthermore, the other end of the tension spring 50 having one end attached to the apparatus main body 11 is attached to a portion between the other end of the moving arm 48 and the bent portion, and the moving arm 48 is centered on the support shaft 48a. In the figure, a rotational biasing force in the clockwise direction is applied.
The roller 48b is disposed between the discs 44a and 44b fixed in the middle of the camshaft 44, and the cam follower 48c has its peripheral surface brought into contact with the peripheral surface of the step cam 49 by the urging force of the tension spring 50. It is in contact. The interval between the discs 44a and 44b is set to be slightly larger than the diameter of the roller 48b.

  The step cam 49 has three cam portions 49 a, 49 b, 49 c on its peripheral surface, and is fixed to a support shaft 51 that is rotatably supported by the apparatus main body 11. A gear 54 that meshes with a gear 53 attached to an output shaft of a stepping motor 52 attached to the apparatus main body 11 is attached to the support shaft 51, and the step cam 49 is moved by the arrow shown in FIG. It is rotationally driven in the direction. With this configuration, when the stepping motor 52 is actuated to rotate the step cam 49, the moving arm 48 swings about the support shaft 48a, and the roller 48b pushes the disk 44a or the disk 44b so that the camshaft 44 is illustrated. 3 in the left-right direction.

Each cam portion 49a, 49b, 49c is in contact with the cam follower 48c and the cam portion 49b so that the cam plate 43B is in a position where the cam follower 41 can come into contact with the cam follower 41 when the cam follower 48c and the cam portion 49a contact each other. When the cam follower 48c and the cam portion 49c come into contact with each other so that the cam plate 43A comes into contact with the cam follower 41, the cam shaft 44C comes into contact with the cam follower 41. Each is formed in a shape to be moved.
The above-described cam follower 41, the printing pressure spring 42, the multistage cam 43, the press roller locking means (not shown), the moving arm 48, and the step cam 49 constitute a press roller contact / separation mechanism 55. By the operation, the press roller 13 selectively occupies the separated position shown in FIG. 2 and the press contact position shown in FIG.

  As shown in FIG. 1, a switching member 10 that switches the transport path of the paper P is disposed on the transport path of the paper P on the left side of the contact position between the plate cylinder 12 and the press roller 13. The switching member 10 made of a plate material having substantially the same width as that of the plate cylinder 12 and the press roller 13 is rotatably supported on the downstream end thereof in the sheet conveying direction coaxially with the driven roller 88, and is shown in FIG. As a result of the operation of 123, the upstream end in the sheet conveying direction formed with an acute cross section is selectively positioned at a first position indicated by reference numeral 10a and a second position indicated by reference numeral 10b in FIG. When the switching member 10 occupies the first position 10a, the tip of the switching member 10 is located close to the peripheral surface of the press roller 13 and does not interfere with the clamper 19 on the plate cylinder 12, and occupies the second position 10b. The tip of the plate cylinder 12 is placed close to the peripheral surface of the plate cylinder 12. The paper P passing between the plate cylinder 12 and the press roller 13 is guided to the paper discharge unit 6 when the switching member 10 occupies the first position 10a, and the switching member 10 moves to the second position 10b. When occupied, it is guided to the auxiliary tray 8 through the space between the guide plate 27 and the guide plate 56 fixed to the apparatus main body 11.

  A plate making unit 3 is disposed in the upper right part of the apparatus main body 11. The plate making unit 3 includes a master holding member 57, a platen roller 58, a thermal head 59 as a punching unit, a cutting unit 60, a master stock unit 61, a tension roller pair 62, a reverse roller pair 63, and the like. The plate making section 3 generates a plurality of heat generating elements which are the heat generating sections of the thermal head 59 according to the image signal, and selectively melts and punches a thermoplastic resin film of the master 64 described later to form a punching pattern according to the image signal. A double-sided printing master 65 (see FIG. 4A) having a first plate-making image 65A and a second plate-making image 65B as shown in FIG. 4, or a first plate-making image 65A and a second plate-making image 65B. A single-sided printing master 66 (see FIG. 4B) having a third plate-making image 66A having an image amount area for two sides is made. The first plate-making image 65A is formed at a position corresponding to the front surface region shown in FIG. 1 when the double-sided printing master 65 is wound on the outer peripheral surface of the plate cylinder 12, and the second plate-making image 65B is a back surface region. And corresponding positions. FIG. 4 is a view of the state wound around the plate cylinder 12 as seen from the film surface.

In this embodiment, as shown in FIG. 4A, plate making is performed such that a predetermined blank portion SK is provided between the first plate making image 65A and the second plate making image 65B. For this reason, the double-sided printing master 65 is longer than the single-sided printing master 66 by a predetermined amount e.
The master holding member 57 is provided on each side plate pair (not shown) of the apparatus main body 11 and supports both ends of the core portion 64b of the master roll 64a formed by winding the master 64 in a roll shape so as to be rotatable and detachable. ing. As the master 64, a thickness of 40 μm obtained by bonding a thermoplastic resin film having a thickness of 1.6 μm on a Japanese paper as a porous support is used.
The platen roller 58 provided on the left side of the master holding member 57 is rotatably supported on a side plate (not shown) of the apparatus main body 11 and is driven to rotate by the plate-making driving means 124. A stepping motor is used for the plate-making driving means 124.

  A thermal head 59 having a large number of minute heating elements arranged below the platen roller 58 and arranged in the main scanning direction is attached to a side plate (not shown) of the apparatus main body 11 and is attached with a biasing means (not shown). The surface of the heating element is pressed against the platen roller 58 by force. The thermal head 59 is connected to a thermal head drive circuit (not shown). This thermal head drive circuit selectively generates heat from the heating elements of the thermal head 59 that contacts the thermoplastic resin film surface of the master 64 in accordance with an image data signal that is an image signal, and heat-melts and punches the master 64. Perform plate making.

  As shown in FIG. 1, a known cutting means 60 for cutting the master 64 is disposed on the left side of the platen roller 58 and the thermal head 59. A master stock section 61 is disposed below the cutting means 60 on the downstream side in the master conveyance direction. The master stock portion 61, which is a space for temporarily storing the double-sided printing master 65 or the single-sided printing master 66, is partitioned by a plurality of plate members, and a suction fan (not shown) is provided at the innermost portion. It is arranged. When the suction fan is operated, a negative pressure is generated in the master stock unit 61 that is a sealed space, and the master stock unit 61 is a master for double-sided printing 65 or a master for single-sided printing 66 that has been transported after plate making. It is stored towards the innermost part of. A tension roller pair 62 is disposed at a portion between the cutting means 60 and the master stock portion 61. A reverse roller pair 63 is disposed downstream of the master stock unit 61 in the master conveyance direction. The rollers on one side of the tension roller pair 62 and the reverse roller pair 63 are rotated by a drive motor (not shown) to feed the master in the master stock unit 61 toward the plate cylinder 12.

The digital image signal that is the source of the image on the master is formed by reading an original with the image reading unit 7 disposed in the upper part of the apparatus main body 11, and the double-sided printing apparatus is connected to an external processing apparatus such as a personal computer. In some cases, it is formed by the output of a digital document created on a computer.
As shown in FIG. 1, the image reading unit 7 reads the originals 91A and 91B. That is, each document placed on the document placing table 92 is subjected to exposure reading while being conveyed in the direction of the arrow Y1 by the rotation of the separation roller 93, the front document conveyance roller pair 94, and the rear document conveyance roller pair 95. . At this time, when there are a large number of documents, only the lowermost document is conveyed by the action of the separating blade 96. One roller of the rear document transport roller pair 95 is rotationally driven by a document transport roller motor 128 serving as a document drive unit. The front document transport roller pair 94 is rotationally driven in conjunction with the drive of the rear document transport roller pair 95. When reading the images of the originals 91A and 91B, the reflected light from the surface of the original illuminated by the fluorescent lamp 99 serving as the light source is reflected by the mirror 98 while being conveyed on the contact glass 97 forming a part of the image reading means. This is performed by entering the image sensor 101 including a CCD (charge coupled device) through the lens 100. The document whose image has been read is discharged onto a document tray (not shown). The electrical signal photoelectrically converted by the image sensor 101 is input to an analog / digital (A / D) conversion board (not shown) in the apparatus body cabinet 50, converted into a digital image signal, and stored in the image memory 135.

  In this embodiment, a configuration is adopted in which a double-sided printing master 65 or a single-sided printing master 66 made by the plate-making unit 3 provided in the double-sided printing device is wound around a plate cylinder 12 that is detachable from the apparatus main body 11. However, it is also possible to make the masters 65 and 66 by a plate making apparatus provided separately from the stencil forming apparatus, and to attach the plate cylinder 12 on which the masters 65 and 66 are selectively wound to the apparatus main body 11. is there.

  A sheet feeding unit 4 is disposed below the plate making unit 3. The paper feed unit 4 includes a paper feed tray 67, a paper feed roller 68, a separation roller 69, a separation pad 70, a registration roller pair 71, and the like. A paper feed tray 67 capable of stacking a large number of sheets P on the upper surface is supported by the apparatus main body 11 so as to be movable up and down, and is moved up and down by a paper feed driving means 125 (see FIG. 6) including a lifting means. A pair of side fences 72 are provided on the upper surface of the paper feed tray 67 on which A3 size paper P can be placed vertically and supported by a rail member (not shown) so as to be movable in the paper width direction perpendicular to the paper transport direction. . On the free end side of the paper feed tray 67, a plurality of paper size detection sensors 73 for detecting the size of the paper P stacked and fed are provided. The paper P is basically set with a paper size adapted to the sizes of the first image area 4 and the second image area 5. In other words, when the maximum print size during single-sided printing is A3 size, the maximum print size for double-sided printing is roughly A4 size, and the maximum sheet passing paper is also A4. Although the paper passing direction is the short side direction, the paper may be set in different sizes and orientations during single-sided printing and double-sided printing.

  Above the paper feed tray 67, a paper feed roller 68 having a high frictional resistance member on the surface is disposed. The paper feed roller 68 is rotatably supported by a bracket (not shown) supported by the apparatus main body 11 so as to be swingable. When the paper feed tray 67 is lifted by lifting means (not shown), paper is fed with a predetermined pressure contact force. The uppermost sheet P on the tray 67 is pressed against. The paper feed roller 68 is rotationally driven by the paper feed driving means 125.

  On the left side of the paper feed roller 68, a separation roller 69 and a separation pad 70 each having a high friction resistance member on the surface are disposed. The separation roller 69 is drivingly connected to the paper feed roller 68 via a timing belt 69a, and is driven to rotate in the same direction in synchronization with the rotation of the paper feed roller 68. The separation pad 70 is pressed against the separation roller 69 by a biasing force of a biasing means (not shown).

  A registration roller pair 71 is disposed on the left side of the separation roller 69 and the separation pad 70. The registration roller pair 71 including the driving roller 71a and the driven roller 71b transmits the rotational driving force from the plate cylinder driving unit 121 by a driving force transmitting unit (not shown) such as a gear or a cam, so that the driving roller 71a is connected to the plate cylinder. 12, the paper P is fed toward the printing unit 2 at a predetermined timing by a driven roller 71 b that rotates at a predetermined timing in synchronization with the driven roller 71 and is in pressure contact with the driving roller 71 a.

  A plate discharging unit 5 is disposed on the upper left side of the printing unit 2. The plate discharging unit 5 includes an upper plate discharging member 74, a lower plate discharging member 75, a plate discharging box 76, a compression plate 77, and the like. The upper plate removal member 74 has a drive roller 78, a driven roller 79, an endless belt 80, etc., and the endless belt is driven by the drive roller 78 being rotated in the clockwise direction in the drawing by the plate discharge drive means 126 (see FIG. 6). 80 moves in the direction of the arrow in FIG. The lower plate removing member 75 includes a driving roller 81, a driven roller 82, an endless belt 83, and the like, and transmits the driving force of the plate discharging driving means 126 that rotationally drives the driving roller 78 by a driving force transmitting means (not shown) such as a gear or a belt. As a result, the drive roller 81 is rotationally driven in the counterclockwise direction in the figure, whereby the endless belt 83 moves in the arrow direction in FIG. Further, the lower plate removing member 75 is movably provided by a moving means (not shown) included in the plate discharging driving means 126, and an endless belt 83 located on the outer peripheral surface of the driven roller 82 is located at the position shown in the figure. It selectively occupies a position in contact with the outer peripheral surface.

  A plate removal box 76 for storing a used master therein is provided detachably with respect to the apparatus main body 11. A compression plate 77 that pushes the used master carried by the upper plate removal member 74 and the lower plate removal member 75 into the plate release box 76 is supported by the apparatus main body 11 so as to be movable up and down, and is included in the plate discharge drive means 126. It is moved up and down by the lifting means.

  A paper discharge unit 6 is disposed below the plate discharge unit 5. The paper discharge unit 6 includes an air knife device 150, a peeling claw 84, a paper discharge conveying member 85, a paper discharge tray 86, and the like. A plurality of peeling claws 84 are arranged in the width direction of the plate cylinder 12, and are respectively integrally attached to a support shaft that is swingably supported by the apparatus main body 11. The plurality of peeling claws 84 are swung by a claw rocking means (not shown), and the tips of the peeling claws 84 are located close to the peripheral surface of the plate cylinder 12 and the tips of the plates are in order to avoid obstacles such as the clamper 19. It selectively occupies a position away from the outer peripheral surface of the body 12. The claw swinging means (not shown) transmits the driving force from the plate cylinder driving means 121 shown in FIG. 6 by the driving force transmitting means (not shown), and swings the peeling claw 84 in synchronization with the rotation of the plate cylinder 12. The air knife device 150 is for assisting the peeling of the paper P by the peeling claw 84, and is used to guide the blower fan 151 and the air from the fan 151 to the plate cylinder 12 near the paper discharge claw 84 in a thin layer. And a duct 152.

  A paper discharge conveying member 85 disposed below the peeling claw 84 and to the left of the switching member 10 includes a driving roller 87, a driven roller 88, an endless belt 89, a suction fan 90, and the like. A plurality of roller-shaped drive rollers 87 are attached to a support shaft (not shown) rotatably supported on a unit side plate (not shown) at a predetermined interval, and each is integrally driven to rotate by a paper discharge driving means 127 (see FIG. 6). Is done. A plurality of driven rollers 88 are also provided on a support shaft (not shown) rotatably supported on the same side plate at equal intervals with each drive roller 87, and each drive roller 87 and each corresponding driven roller 88 corresponding to this have a plurality of holes. The endless belts 89 having the above are stretched over each other. A suction fan 90 is disposed below the driving roller 87, the driven roller 88, and the endless belt 89. The paper discharge conveying member 85 sucks the paper P onto each endless belt 89 by the suction force of the suction fan 90, and transports the paper P in the direction of the arrow in FIG. A paper discharge tray 86 on which the paper P conveyed by the paper discharge conveyance member 85 is stacked is provided with one end fence 91 movable in the paper conveyance direction and a pair of side fences 92 movable in the paper width direction. And have.

  As shown in FIG. 1, a dog 133 serving as a phase timing detection plate is attached to the outer surface of a flange (not shown) constituting the plate cylinder 12, and a photo attached to the apparatus main body 11 near the periphery of the plate cylinder 12. A home position sensor 134 composed of an interrupter is provided. The home position sensor 134 detects the dog 133 and outputs a phase timing signal to the control means 160 when the plate cylinder 12 occupies a position where the clamper 19 faces the press roller 13.

  In the vicinity of the peeling claw 84, a rear end detection sensor 170 is provided as a master detection means for detecting the rear end of either the double-sided printing master 65 or the single-sided printing master 66 wound around the plate cylinder 12. Has been. In this embodiment, the rear end detection sensor 170 is disposed at a position for detecting the rear end 65C of the double-sided printing master 65 when the plate cylinder 12 occupies the home position at the predetermined position shown in FIG. . The rear end detection sensor 170 is a well-known optical reflection type sensor including an irradiation unit that irradiates light toward the outer peripheral surface of the plate cylinder and a light receiving unit, and is a rear end 65C of the double-sided printing master 65 (FIG. 4). When (a) is detected, a Low signal is output, and when there is no master, a Hi signal is output. In this embodiment, when plate making is started, detection light is irradiated from the rear end detection sensor 170 toward the plate cylinder 12.

  FIG. 5 shows the operation panel 103 of the duplex printing apparatus. In the figure, an operation panel 103 provided on the upper front surface of the apparatus main body 11 has a print start key 104, a stop key 105, a ten key 106, a paper size key 107, a paper thickness key 108, a duplex printing key 110, It has a single-sided printing key 111, display means 113, 114, 115 made of LEDs, a display device 116 made of LCD (liquid crystal panel), and the like. In the numeric keypad 106, an enter key 106e for returning the control of the duplex printing machine to the initial state is provided. Here, the LED and the LCD constitute display means of the operation panel 103.

  The start key 104 is pressed when starting the operation of the double-sided printing apparatus. When the start key 104 is pressed, the plate making operation is performed after the plate discharging operation and the document reading operation are performed, and then the plate making operation and the printing operation are performed. Thus, the duplex printing apparatus is in a print standby state. A stop key 104 is pressed to stop the operation of the apparatus and inputs a stop signal to the control means 160. The numeric keypad 106 is pressed when inputting a numerical value such as the number of printed sheets. The paper thickness key 108 is pressed when inputting the paper thickness arbitrarily. The paper size key 107 is pressed when an arbitrary paper size is input, and the paper size input with the paper size key 107 has priority over the paper size detected by the paper size detection sensor 73. The duplex printing key 110 is pressed before the printing start key 104 is pressed when the duplex printing apparatus 1 performs the duplex printing operation. The single-sided printing key 111 is pressed before the start key 104 is pressed when the double-sided printing apparatus 1 performs a single-sided printing operation. The display device 116 displays various results determined by the control means 160, such as operation instruction information for the operator, the type of the master 64, and the like.

FIG. 6 shows a block diagram of a control system used in the duplex printing apparatus 1. In the figure, the control means 160 is constituted by a known microcomputer, and has a CPU 161, ROM 162, and RAM 163 therein, and is provided inside the apparatus main body 11.
The CPU 161 is based on various signals from the operation panel 103, detection signals from various sensors provided in the apparatus main body 11, and an operation program called from the ROM 131, the printing unit 2, the plate making unit 3, the paper feeding unit 4, and the discharge plate. Operation of the drive unit provided in the unit 5, the paper discharge unit 6, the image reading unit 7, the re-feeding resist contact / separation mechanism 40 provided in the re-feed unit 9, and the operation of the solenoid 123 that operates the switching member 10. Further, the pump 196 is driven by the ink amount detection adjusting means 133 in accordance with the ink amount signal in the plate cylinder unit 162, and the plate cylinder unit 162 is connected to the apparatus body 11 side of the plate cylinder unit 162. It detects and controls the operation of the entire duplex printing apparatus 1. The ROM 162 stores an operation program for the entire duplex printing apparatus, and this operation program is appropriately called by the CPU 161.

  The RAM 163 stores master type information, paper size and orientation information, and a printable state based on a combination of master information and paper size information as data. In particular, when an input signal indicating that plate making has been performed (information that plate making has been performed in either the double-side plate making mode or the single-side plate making mode) is received, it is determined whether or not the double-side plate making mode has been made based on the input signal. When it is determined that the master for which the plate making has been made is the master for double-sided printing 65 as the master for divided plate making, the double-side plate making flag DFIG is stored (DFIG = 1) and the master is made. When the single-side printing master 66 is made, the double-side plate making flag DFIG is stored off (DFIG = 0), and the type of master on which the latest plate making is made is stored in the RAM 163.

Further, the RAM 163 has a function of temporarily storing calculation results of the CPU 161, a function of storing data signals and ON / OFF signals set and input from various keys and various sensors on the operation panel 103 as needed. Yes. The ROM 131 and the RAM 163 form a storage device.
The control unit 160 uses the phase timing signal from the home position sensor 134 and the rotation pulse signal generated every time the plate cylinder driving unit 121 rotates by a certain angle to determine the rotation phase position (timing) of the plate cylinder 12 in real time. Detect and recognize.

  Further, upon receiving an input signal indicating that the plate making has been performed in the duplex printing mode, the control means 160 determines that the plate making has been performed in the duplex printing mode, and stores it in the storage device (DFIG = 1). Only when the two-side plate making is stored in the storage device in this way, when the plate cylinder 12 is replaced, the type of the master 64 on the plate cylinder is detected by the rear end detection sensor 170 which is a master detection means. And a function as display control means for displaying the determined master type on the display device 116 on the operation panel.

Further, the control means 160 is capable of detecting insertion / removal to the fitting recess 721 that is the plate cylinder mounting portion of the plate cylinder 12 of the double-sided plate making when it is stopped in the middle of printing or waiting in a normal state where printing is possible. An input signal from the dip switch 185 for setting the type of the wound master is that the plate cylinder of the double-side plate making is re-inserted by the plate cylinder removal difference detecting means having the column J1 and the plate cylinder side contact column J2. Is detected, the display control means has a function as display control means for displaying on the display device 116 that printing on the plate cylinder of the double-side plate making can be resumed by the operation panel.
Further, the control means 160 performs double-side plate making by means of a plate cylinder displacement detection means provided with a main body side contact row J1 and a plate cylinder side contact row J2 when printing is stopped for error processing in accordance with an error signal during printing. When it is detected that the plate cylinder is inserted again, it is determined that the same plate cylinder has been inserted and removed, and the same printing function as that before stopping is provided.

Further, the control unit 160 detects that the plate cylinder 12 has been replaced and plate-making has been performed in the duplex printing mode (DFIG = 1) while being stopped in the middle of printing or waiting in a normal state where printing is possible. If this is the case, resumption of printing is allowed only when both the plate making mode detected by the trailing edge detection sensor 170 and the plate making mode (DFIG = 1) written in the storage device are duplex printing, and otherwise Has a function of processing so that reprinting cannot be performed again.
Furthermore, the control means 160 is used when printing can be resumed after replacing the plate cylinder, that is, when the detected plate-making mode and the plate-making mode (DFIG = 1) written in the storage device are both double-sided. The display control means has a function as display control means for displaying on the operation panel a plate making mode before stoppage or standby, that is, that printing can be resumed with double-sided printing.

Further, the control means 160, when the printing input is held again after replacing the plate cylinder, that is, the detected plate making mode is mounted on the single-sided printing master 66, and this is the plate making mode written in the storage device. If it does not match (DFIG = 1), it is displayed on the operation panel that printing cannot be resumed and it is necessary to make the plate again, and it is held in a state waiting for the input of a plate making instruction again. It has a function.
The operation of the double-sided printing apparatus 1 equipped with the control means 160 having all such control functions will be described in order according to the plate making and plate-making process routine of FIG. 9 and the print control routines of FIGS.

  In this embodiment, prior to printing, two documents 91A and 91B are set on the mounting table 92, and duplex printing starts. Here, the document 91A is a front document serving as a first document, and the document 91B is a back document serving as a second document. When the duplex key 110 on the operation panel 103 shown in FIG. 5 is pressed by the operator and the start key 108 is pressed, step A1 in the printing control shown in FIG. 10 is reached. move on. The control process in step A3 is performed as a plate making and plate making process routine shown in FIG.

  In step S1 of the plate making and plate making process routine, plate making is started. First, the document conveying roller motor 128 is driven in the image reading unit 7 to read the document image of the first sheet (first document 91A). The read original image is stored in the image memory 135 as a digital image signal of the front surface image, and the rear end detection sensor 170 is operated to irradiate the detection light toward the outer peripheral surface of the plate cylinder 12. When the reading operation of the first original 91A is completed and the digital image signal is stored in the image memory 135, the reading operation of the second original (second original 91B) is continuously performed on the first original. Done at a similar speed. The read document image is stored in the image memory 135 as a digital image signal of the back image. In parallel with the image reading operation for the first document 91A, the plate discharging unit 5 performs the plate discharging operation. The plate cylinder 12 from which the used master has been peeled off from the outer peripheral surface stops at the plate feeding standby position, and the clamper 19 is opened by an opening / closing means (not shown).

In the plate making unit 3, the heating element of the thermal head 59 is used based on the digital image signal stored in the memory 135 in order to form the first plate making image 65 </ b> A and the second plate making image 65 </ b> B on the thermoplastic resin film surface of the master 64. While heating, the master feed motor 124B is driven to transport the heat-sensitive stencil master 64, and the first plate-making image 65A and the second plate-making image 65B are each made to form a double-sided printing master 65.
The double-sided printing master 65 on which the plate-making images 65A and 65B are formed is stored in the master stock unit 61, and when the plate-removing operation is completed and the double-sided printing apparatus 1 is in a plate feeding standby state, the reversing roller pair 63 is operated. It is conveyed toward the open clamper 19. Thereafter, the plate cylinder 12 is intermittently rotated, and the double-sided printing master 65 is wound around the plate cylinder 12. When all the image data for two sheets is sent from the image memory 135, the cutting means 60 is activated to cut the double-sided printing master 65. The cut master for duplex printing 65 is pulled out from the plate making unit 3 by the rotation of the plate cylinder 12, and the plate cylinder 12 is stopped at the home position to complete the plate making operation and the plate feeding operation.

  The completion of the plate making in step S2 is determined, for example, based on whether or not the cutting means 60 is driven, and storage processing that the double-sided printing master 65 has been made is performed with the double-side plate making flag DFIG being on (DFIG = 1). Information is stored in the RAM 163. When the plate making is completed, the process proceeds to step S3, where it is determined whether or not the current plate making is double-side plate making. If the double-side plate making flag DFIG is on (DFIG = 1), the other-side single-side plate making master 66 is made in step S4. If (DFIG = 0), the process proceeds to step S5.

  In step S4, it is determined whether the paper P on the paper feed tray 67 is a paper that can be printed on both sides. Here, the paper size information from the paper size detection sensor 73 is fetched in preference to the paper size information from the paper size key 107, and the size and orientation of the paper P are determined. In this embodiment, as the type of paper that can be printed on both sides, JIS standard A4 is standardly set as the paper size, and the paper orientation is set to a loading direction that can be conveyed vertically in the paper conveyance direction. If a paper capable of duplex printing is set in step S4, the process proceeds to step S6 to enable the operation of the duplex printing key 110 and the printing star key 104, and further, the display units 113A and 113A of the display means 113 and 115 are displayed. 115A is turned on, and the process proceeds to step S8.

If it is determined in step S4 that paper that cannot be printed on both sides is set and the process proceeds to step S7, only the operations of the single-sided printing key 111 and the printing start key 104 necessary for single-sided printing are valid. The display portions 114A and 115A of 114 and 115 are turned on, and the process proceeds to step S8.
On the other hand, it is assumed that the signal from the rear end detection sensor 170 is Hi in Step S3 described above and reaches Step S5. Here, it is determined whether or not the paper P on the paper feed tray 67 is a paper that can be printed on one side. Here, the paper size information from the paper size detection sensor 73 is fetched in preference to the paper size information from the paper size key 107, and the size and orientation of the paper P are determined. In this embodiment, JIS standard A4 landscape or A3 size is used as a standard paper type that can be printed on one side.

In step S5, if a sheet that can be printed on one side is set, the process proceeds to step S10, where the operation of the one-sided printing key 111 and the printing star key 104 is validated, and the display units 114A and 115A of the display means 114 and 115 are turned on. Turn on the light and proceed to step S8.
If the paper on the paper feed tray 67 is not A4 landscape or A3 size, it is determined in step S5 that paper that cannot be printed on one side is set, and the process proceeds to step S9. In step S9, the operations of the duplex printing key 110 and the printing start key 104 necessary for duplex printing are validated, the display portions 113A and 115A of the display means 113 and 115 are turned on, and the process proceeds to step S8.

Since the master type made after the plate making is displayed on the operation panel 103 in this way, even if the plate making by wrong selection is executed, the contents of the plate making can be visually confirmed. Printing by the master can be prevented.
After the appropriate print mode is displayed on the operation panel 103 from the above-described steps S6, S7, S9, and S10, when step S8 is reached, the operator selectively presses the key, and the current print mode, The paper to be used is set, and then the printing process in step S11 is performed.
In the plate mounting operation in step S11, when the plate cylinder 12 stops at the home position, the stepping motor 52 in FIG. 3 operates to rotate the step cam 49 and the press roller locking means (not shown) to operate the cam portion 49a. It is brought into contact with the cam follower 48c. As a result, the movable arm 48 is swung around the support shaft 48a and the cam shaft 44 is moved to a position where the cam plate 43B can be brought into contact with the cam follower 41. Is released.

  Thereafter, the paper feed roller 68, the separation roller 69, the drive rollers 36 and 87, and the suction fans 39 and 90 are respectively driven, and the plate cylinder 12 is driven at a low speed by the drive of the plate cylinder drive means 121. The first sheet P1 is pulled out from the sheet feed tray 67 and the leading end thereof is sandwiched between the registration roller pair 71. When the clamper 19 passes the position corresponding to the switching member 10, the solenoid 123 is actuated to position the switching member 10 at the second position, and then the double-sided printing master 65 wound on the plate cylinder 12. The drive roller 71a is rotationally driven at a predetermined timing when the leading end of the image area of the first plate-making image 65A in the plate cylinder rotation direction reaches a position corresponding to the press roller 13, so that the drawn paper P1 is extracted from the plate cylinder 12. And the press roller 13.

  The cam plate 43B moved to a position where it can come into contact with the cam follower 41 at the predetermined timing disengages its convex portion from the cam follower 41, and the press roller 13 presses the peripheral surface by the biasing force of the printing spring 42. Press contact with the outer peripheral surface of the body 12. As a result, the press roller 13, the paper P1, the first plate-making image 65A forming portion of the double-sided printing master 65, and the plate cylinder 12 are pressed against each other, and the ink supplied to the inner peripheral surface of the plate cylinder 12 by the ink roller 16 is the plate cylinder. The first plate-making image 65A is exuded after being filled in the porous support plate (not shown) and mesh screen (not shown) wound around the plate cylinder 12 and the porous support of the master 65 for double-sided printing. The portion of the double-sided printing master 65 where the first plate-making image 65A is formed is printed by being transferred to the paper P1 through the punching portion.

  The sheet P1, on which the image corresponding to the first plate-making image 65A is printed on the surface by printing, is peeled off from the double-sided printing master 65 on the outer peripheral surface of the plate cylinder by the leading end of the switching member 10, while The re-feeding means 9 is guided by the switching member 10 occupying the position 2. The sheet P 1 guided downward by the switching member 10 passes between the guide plates 27 and 56, has its tip abutted against the fence 8 a, and is placed on the auxiliary tray 8. The sheet P1 transported on the auxiliary tray 8 is transported in the direction of the arrow in FIG. 1 while being held on the endless belt 38 that is rotated by the transport of the transport member drive motor 122 by the suction force generated by the drive of the suction fan 39. The front end (the rear end when the first plate-making image 65A is printed) is brought into contact with the bent end 24a. At this time, since slip occurs between the paper P1 and the endless belt 38, the paper P1 is stopped in a state where the leading end thereof is in contact with the bent end portion 24a. A sensor (not shown) is provided for detecting when the leading edge of the paper P1 comes into contact with the bent end 24a. When the sensor (not shown) detects the leading edge of the paper P1, the drive roller 36 and the suction fan 39 are operated. It is good also as a structure which stops.

  The plate cylinder 12 continues to rotate while the paper P1 is being guided on the auxiliary tray 8, and when the press roller 13 finishes contact with the surface area of the plate cylinder 12, the convex portion of the cam plate 43B becomes the cam follower 41. It occupies the separated position by contacting the Due to the function of the cam plate 43B, the back surface region of the plate cylinder 12 and the press roller 13 are not in pressure contact with each other in the absence of the paper P, and ink transfer to the peripheral surface of the press roller 13 can be prevented. At this time, a press roller locking means (not shown) is operated to hold the press roller 13 in the separated position, and then the stepping motor 52 is operated to rotate the step cam 49 to bring the cam portion 49b into contact with the cam follower 48c. As a result, the moving arm 48 is swung around the support shaft 48a, and the cam shaft 44 is moved to a position where the cam plate 43A can be brought into contact with the cam follower 41.

Almost simultaneously with the above-described operation, the paper feed roller 68 and the separation roller 69 are driven, the second sheet P2 is drawn from the paper feed tray 67, and the leading end thereof is sandwiched between the registration roller pair 71. Then, the drive roller 71a is rotationally driven at a predetermined timing similar to that described above, and the drawn paper P2 is fed toward the space between the plate cylinder 12 and the press roller 13.
In the press roller contact / separation mechanism 55, when the cam shaft 44 rotates to a position where the convex portion of the moved cam plate 43A can come into contact with the cam follower 41, the operation of the press roller locking means (not shown) is released. At this time, the plate cylinder 12 rotating in synchronization with the camshaft 44 occupies a position where the non-opening portion which is a portion other than the front surface region, the back surface region, and the intermediate region faces the press roller 13. Further, the solenoid 123 is operated until the surface area of the plate cylinder 12 passes through the portion facing the press roller 13 and the clamper 19 occupies the position corresponding to the switching member 10 again. It is displaced from the position to the first position.

  At a predetermined timing when the sheet P2 is fed by the registration roller pair 71, the cam plate 43A disengages the convex portion from the cam follower 41, so that the press roller 13 causes the printing cylinder to move its peripheral surface by the urging force of the printing spring 42. 12 is pressed against the outer peripheral surface. As a result, the press roller 13, the paper P2, the first plate-making image 65A forming portion of the double-sided printing master 65, and the plate cylinder 12 are pressed against each other, and the ink supplied to the inner peripheral surface of the plate cylinder 12 by the ink roller 16 is the plate cylinder. The image is transferred to the paper P2 through the 12 openings, a porous support plate (not shown), a mesh screen (not shown), and a perforated portion of the first platemaking image 65A.

The paper P2 on which an image corresponding to the first plate-making image 65A is printed is guided to the paper discharge conveyance member 85 by the switching member 10 occupying the first position, and from the front end portion thereof by the peeling claw 84. It peels from the double-sided printing master 65 on the outer peripheral surface. The peeled paper P2 falls downward and is sent to the paper discharge conveying member 85 and then discharged onto the paper discharge tray 86.
After the sheet P2 is fed by the registration roller pair 71, it is slightly earlier than the leading end of the image area of the second plate-making image 65B in the plate cylinder rotation direction of the double-sided printing master 65 reaches the position corresponding to the press roller 13. The solenoid 33 is actuated at a predetermined timing, which is the timing, and the swing arm 32 is swung in the clockwise direction in FIG. 2 about the support shaft 32a. As a result, the re-feeding registration roller 23 is swung from the separation position to the press-contact position, and the sheet P1 stopped with the leading end abutting against the bent end 24a abuts on the plate cylinder 12 and is driven to rotate. The press roller 13 is in contact with the peripheral surface.

  The paper P1 brought into contact with the peripheral surface of the press roller 13 by the re-feeding registration roller 23 is conveyed to the downstream side in the rotational direction by the rotational force of the press roller 13, and the paper guide plate 31 and the rollers 28, 29, The sheet 30 is conveyed toward the contact portion with the plate cylinder 12 while being in close contact with the peripheral surface of the press roller 13. At this time, an image corresponding to the first plate-making image 65A is printed on the surface of the paper P1, but since the paper P1 is in close contact with the peripheral surface of the press roller 13 by the action of the refeed guide member 22, once. The sheet P1 in contact with the peripheral surface of the press roller 13 is not displaced, and occurrence of problems such as rubbing dirt or thickening of the image line is prevented. Then, after the rear end and the intermediate region of the paper P2 pass through the position corresponding to the press roller 13, the paper P1 is moved to the plate cylinder 12 and the press roller at the timing when the leading end of the back surface region reaches the position corresponding to the press roller 13. 13 is sent to the abutting part.

As a result, the press roller 13, the paper P1, the second plate-making image 65B forming portion of the double-sided printing master 65, and the plate cylinder 12 are pressed against each other, and the ink supplied to the inner peripheral surface of the plate cylinder 12 by the ink roller 16 is the plate cylinder. The second plate-making image 65B of the master for double-sided printing 65 is formed by being transferred to the paper P1 through the 12 openings, a porous support plate (not shown) and a mesh screen (not shown), and a perforation portion of the second plate-making image 65B. The part is printed.
The paper P1 on which the image corresponding to the first plate-making image 65A is printed on the front surface and the image corresponding to the second plate-making image 65B is printed on the back surface is transferred to the paper discharge conveyance member 85 by the switching member 10 occupying the first position. And is peeled from the double-sided printing master 65 on the outer peripheral surface of the plate cylinder by the action of the air sprayed from the air knife 152 and the peeling claw 84. The peeled sheet P1 falls downward and is sent to the paper discharge conveying member 85 and then discharged onto the paper discharge tray 86. Thus, the plate-making operation of the double-sided printing master 65 is completed, and the printing operation is completed. Move on.

  At the time of printing in step S11, a predetermined blank portion S is provided between the first plate-making image 65A and the second plate-making image 65B of the double-sided printing master 65, and the double-sided printing master 65 is placed on the outer periphery of the plate cylinder 12. Since the intermediate region is formed when wound on the surface, the trailing edge of the paper P2 sent from the paper feeding unit 4 and the leading edge of the paper P1 sent from the refeeding means 9 may overlap. It is prevented and good printing can be performed. Further, when the paper P1 is fed again from the refeeding means 9, the ink from the paper P1 is retransferred to the surface of the press roller 13 by coming into contact with the printing surface of the paper P1. Since the surface has ink repellency and the cleaning roller 26 cleans the peripheral surface of the press roller 13, the amount of re-transferred ink from the paper P 1 to the peripheral surface of the press roller 13 is reduced and from the peripheral surface of the press roller 13. The removal of the retransfer ink is promoted, and the retransfer of the ink from the press roller 13 to the back surface of the paper P can be prevented during the following printing.

When the plate making and plate making routines in step S11 are completed and the process returns to step A1 of the printing control routine of FIG. 10, the process proceeds to step A2 based on the determination after the plate making. In step A2, it is determined whether or not the latest double-sided plate making flag DFIG stored is on (DFIG = 1). If on, the process proceeds to step A4, and if off, the process proceeds to step A5 in FIG.
Assuming that the plate cylinder 12 winds the double-side plate making master, when step A4 is reached, the number of prints is set in the double-sided printing apparatus 1 by the numeric keypad 106 and waits for the print start key 104 to be pressed. When pressing of the print start key 104 is detected, the printing operation starts. In this printing operation, the plate cylinder 12 is rotationally driven at the printing speed after the cam shaft 44 is moved to a position where the cam plate 43B can come into contact with the cam follower 41 as in the case of printing, and the switching member 10 is moved. It is switched and held at the second position 10b. After rotation of the plate cylinder 12 is started, the first sheet P1 is fed from the sheet feeding unit 4, and the fed sheet P1 is temporarily stopped by the registration roller pair 71 and then fed at the same timing as the trial printing. The The sheet P1 is pressed against the first plate-making image 65A of the double-sided printing master 65 by the press roller 13, whereby an image corresponding to the first plate-making image 65A is printed on the surface. The sheet P1 on which the image is printed is peeled and guided by the switching member 10 occupying the second position, conveyed onto the auxiliary tray 8, and stopped in a state where the leading end is in contact with the bent end 24a. .

  After that, the press roller locking means (not shown) is actuated to hold the press roller 13 in the separated position, and the cam shaft 44 is moved to a position where the cam plate 43A can come into contact with the cam follower 41. The operation of the press roller locking means is released. Almost simultaneously with this operation, the second sheet P2 is fed from the sheet feeding unit 4, and the sheet P2 is temporarily stopped by the registration roller pair 71 and then fed toward the printing unit 2 at the same timing as the sheet P1. Is done. The switching member 10 is positioned at the first position 10 a to avoid a collision with the clamper 19, and is then positioned again at the second position 10 b after passing the clamper 19.

  The fed paper P2 is pressed against the first plate-making image 65A of the double-sided printing master 65 by the press roller 13, and after the image corresponding to the first plate-making image 65A is printed on the surface, it occupies the second position 10b. The separation member 10 is guided to be peeled off and conveyed onto the auxiliary tray 8. At this time, the solenoid 33 is actuated at the same timing as the trial printing, and the paper P1 retained on the auxiliary tray 8 is conveyed to the printing unit 2 by the rotational force of the press roller 13. After the rear end of the sheet P2 passes through the contact portion between the plate cylinder 12 and the press roller 13, the sheet P1 passes through a position where the intermediate area of the plate cylinder 12 faces the press roller 13, and the back area is the press roller. 13 is sent to the contact portion between the plate cylinder 12 and the press roller 13 at a timing facing the plate 13, and is pressed against the second plate-making image 65B of the double-sided printing master 65 by the press roller 13, whereby the second plate-making image is formed on the back surface thereof. An image corresponding to 65B is printed.

  During the above-described operation, the solenoid 123 is actuated immediately before the intermediate region of the plate cylinder 12 occupies the position facing the press roller 13, and the switching member 10 is displaced from the second position 10b to the first position 10a. Thus, the rear end of the paper P2 guided by the switching member 10 is guided onto the auxiliary tray 8 through a slight gap between the lower surface of the switching member 10 and the peripheral surface of the press roller 13 facing the same surface. Then, the leading edge of the sheet P1 conveyed subsequently is guided to the sheet discharge conveying member 85 along the upper surface 10b of the switching member 10. The paper P <b> 1 is peeled off from the double-sided printing master 65 by the peeling claw 84, transported by the paper discharge transport member 85, and discharged onto the paper discharge tray 86.

The third sheet P3 is fed from the sheet feeding unit 4, and the sheet P3 is temporarily stopped by the registration roller pair 71 and then fed toward the printing unit 2 at the same timing as the sheet P1. The switching member 10 is positioned at the first position 10 a to avoid a collision with the clamper 19, and is positioned again at the second position 10 b after passing the clamper 19. The fed paper P3 is guided on the auxiliary tray 8 by the switching member 10 after an image corresponding to the first plate-making image 65A is printed on the surface. Then, the solenoid 33 is actuated at a predetermined timing, and the paper P2 stopped on the auxiliary tray 8 is conveyed to the printing unit 2. The sheet P2 is sent to the contact portion between the plate cylinder 12 and the press roller 13 at the same timing as the above-described sheet P1, and an image corresponding to the second plate-making image 65B is printed on the back surface thereof. The switching member 10 is displaced from the second position to the first position at the same timing as described above, and the rear end of the sheet P3 is between the lower surface of the switching member 10 (the downward surface in FIG. 1) and the peripheral surface of the press roller 13. It is guided on the auxiliary tray 8 through a slight gap therebetween. Following this, the leading edge of the paper P2 conveyed from the auxiliary tray 8 is guided to the paper discharge conveying member 85 along the upper surface 10b of the switching member 10, and the paper P2 is peeled off by the peeling claw 84 by the double-sided printing master 65. After being further peeled off, the sheet is conveyed by the sheet discharge conveying member 85 and discharged onto the sheet discharge tray 86.
The printing start and continuation process in step A4 proceeds to steps A4, A6, and A8 while the stop switch 105 is not pressed, and the printing control is repeated. When the stop switch 105 is pressed during such a printing process, the process proceeds from step A6 to step A7.

In step A7, the door cover 120 is opened, and it is determined whether or not the door cover 120 is normally opened, for example, replenishment of paper P, plate cylinder replacement or the like. If it is open in response to an error such as out of paper or paper feed failure as determined by the control means 160, the process proceeds to step A10.
When the door cover 120 is opened in response to the error and step A10 is reached, a countermeasure for returning to the normal state is taken in response to the error, and then the door cover 120 is closed, returning to step A4 and resuming printing in step A4. Is made. In this case, it is appropriate to resume printing in the original print mode by canceling the error, and printing is resumed without display on the display device 116 of the operation panel 103.

  When it is determined in step A7 that the door cover 120 is normally open and the process reaches step S9, the detection of drum replacement and the subsequent closing of the door cover 120 are awaited. That is, the plate cylinder unit 162 before replacement is fitted into the plate cylinder receiving frames 172 and 173 before and after the plate cylinder mounting portion provided in the apparatus main body 11. By removing the plate cylinder unit 162 in this state from the front and rear plate cylinder receiving frames 172 and 173, the main body side contact line J1 and the plate cylinder side contact line J2 on the signal line connected to the control means 160 are pulled out. This interruption is memorized. Then, instead of the plate cylinder unit 162 before replacement, a new plate cylinder unit 162 is assumed to be fitted to the front and rear plate cylinder receiving frames 172 and 173. In this case, the control means 160 stores a plate cylinder recognition signal before the main body side contact row J1 and the plate cylinder side contact row J2 are shut off. Here, when the signal line is turned on by reconnection after the main body side contact row J1 and the plate cylinder side contact row J2 are inserted and removed, a new plate cylinder recognition signal is taken in. As a result, the control unit 160 detects, as the plate cylinder connection detection unit 220, that the plate cylinder 12 has been replaced after detecting the insertion / removal of the plate cylinder 12 into the plate cylinder mounting portion. Note that a pre-printed master is wound in advance in the new plate cylinder recognition signal, and data indicating whether it is a double-sided master or a single-sided master is also input by the dip switch 185. Whether or not the cylinder recognition signal is appropriate is unknown.

  Thereafter, when closing of the door cover 120 is detected, the process proceeds from step A9 to step A11. Here, the memory (DFIG = 1) in which the plate making is performed in the duplex printing mode in step S2 is detected in advance, and it is confirmed that the plate making is performed in the duplex printing mode in step A2. This is after the printing cylinder 12 has been replaced after stopping in the middle of printing or waiting in a normal state where printing is possible. Thus, here, the detection processing of the type of master wound around the new plate cylinder is performed. The processing in this step is performed while the plate cylinder 12 is stopped at the home position. Here, it is determined whether the output from the rear end detection sensor 170 is Low or Hi.

  When the output from the trailing edge detection sensor 170 is Low, it is considered that the master trailing edge 65C of the double-sided printing master 65 is detected, and when the output is Hi, it is determined that the relatively short single-sided printing master 66 is detected. Next, when proceeding to Step A12, it is determined whether or not the type of the master wound around the detected new plate cylinder is the same as the master for duplex printing wound around the plate cylinder before the replacement, and double-sided plate-making ( If DFIG = 1), the process proceeds to step A13. Otherwise, the process proceeds to step A14.

  If it is determined that the master is for single-sided printing and the process proceeds to step A14, here, when the master after replacement performs plate making in single-sided printing mode, the paper for double-sided printing is used as it is for single-sided printing. In the drum around which the single-sided printing master is wound, a part of the perforated portion is directly pressed by the press roller 13 so that the surface of the press roller 13 is soiled with ink. It is considered that a problem occurs that the paper surface is soiled during the pressing operation of the paper, and it is necessary to eliminate this.

Therefore, in step A14, when the replaced plate cylinder does not wind the double-side plate-making master, a point indicating that printing cannot be resumed is displayed on the display device 116 of the operation panel 103, for example, “continue printing as it is. "Please review the original and the paper on the paper tray, and make the plate again." Is displayed, and the control means 160 performs an invalid setting process in which printing cannot be resumed even if the print start key 104 is pressed. The processing of the cycle is returned, and the operator is prompted to press the enter key 106a for returning the control to the initial state. By such processing, it is not necessary to waste supplies of ink, paper, etc. due to printing mistakes.
After this, the user recognizes the display on the operation panel 103 and then returns to the initial state again by pressing the enter key 106a, and newly proceeds to steps A1 and A3 to perform the plate making process.

If the master plate detected this time is the same as the plate making in the double-sided printing mode (DFIG = 1) that is stored, the process reaches step A13 from step A12. Here, the master for double-sided printing is placed on the replaced plate cylinder. 65 is determined to be wound, double-sided printing is considered possible, the double-sided printing display 113A, the printing start display 115A are turned on, and a point at which printing can be resumed is displayed. "A drum that can resume printing has been detected. If you want to continue printing , press the print start key 104" is displayed on the display device 116, and the process proceeds to step A15.
In step A15, the process waits for pressing of the print start key 104, and reaches step A8 by pressing.
In this step A8, when normal printing is continued, the process reaches that of step A6 and step A16. Here, it is determined whether or not the preset number of printed sheets (N-1) has been counted, and before the count up. causes the return processing of the control cycle, the count-up reached the step a 21, it enters the termination process.

In step A 21, the printing operation is performed until (N-1) th, and paper PN of N th is printed an image corresponding to the first plate-making image 65A in the fed its surface from the sheet feeding section 4 After being guided onto the auxiliary tray 8, the (N−1) th sheet P (N−1) is printed on the back side thereof with an image corresponding to the second plate-making image and discharged onto the discharge tray 86. . At this time, the press roller locking means (not shown) is operated to hold the press roller 13 in the separated position, and the cam shaft 44 is moved to a position where the cam plate 43C can be brought into contact with the cam follower 41. The operation of the press roller locking means that is not performed is released. At this time, the switching member 10 is maintaining the state which occupied the 1st position 10a.

  Then, the cam follower 41 can be brought into contact with the cam follower 41 at a first timing earlier than the leading end of the image area of the second plate-making image 65B in the plate cylinder rotation direction of the double-sided printing master 65 reaching the position corresponding to the press roller 13. The cam plate 43 </ b> C moved to the position disengages the convex portion from the cam follower 41, and the press roller 13 presses the peripheral surface thereof against the outer peripheral surface of the plate cylinder 12 by the biasing force of the printing pressure spring 42. Thereafter, the solenoid 33 is actuated at a second timing slightly earlier than the leading end of the image area of the second plate-making image 65B in the direction of rotation of the plate cylinder of the double-sided printing master 65 reaches the position corresponding to the press roller 13, and the oscillation is performed. The moving arm 32 is swung clockwise around the support shaft 32a in FIG. As a result, the re-feeding registration roller 23 is swung from the separation position to the press-contact position, and the sheet PN stopped with the leading end abutting against the bent end 24a abuts on the plate cylinder 12 and is driven to rotate. The press roller 13 is in contact with the peripheral surface.

  The sheet PN is sent to the contact portion between the plate cylinder 12 and the press roller 13 at the same timing as the sheet P1, and an image corresponding to the second plate-making image 65B is printed on the back surface thereof. The paper PN on which the image is printed is guided to the paper discharge conveyance member 85 along the upper surface (plate cylinder facing surface) of the switching member 10, and is peeled off from the double-sided printing master 65 by the peeling claw 84. 85, and is discharged onto a discharge tray 86.

  Thereafter, when the press roller 13 finishes contact with the back surface region of the plate cylinder 12, the convex portion of the cam plate 43C comes into contact with the cam follower 41 to occupy the separated position. Due to the function of the cam plate 43C, the surface region of the plate cylinder 12 and the press roller 13 are not pressed against each other in the absence of the paper P, and ink transfer to the peripheral surface of the press roller 13 can be prevented. At this time, the press roller locking means (not shown) is actuated to hold the press roller 13 in the separated position, and then the plate cylinder 12 stops at the home position, and the duplex printing apparatus 1 finishes the printing operation and enters the print standby state again. Become.

Assume that the single-side plate-making flag DFIG is off (DFIG = 0) in step A2 described above, and it is determined that the master wound around the plate cylinder is the single-sided printing master 66, and the process proceeds to step A5.
In this case, as shown in FIG. 11, in step A5, the single-sided printing operation starts. In the single-sided printing operation, the plate cylinder 12 is driven to rotate at the printing speed after the cam shaft 44 is moved to a position where the cam plate 43A can come into contact with the cam follower 41, as in the case of printing. Positioned at the first position 10a. After rotation of the plate cylinder 12 is started, the first sheet P1 is fed from the sheet feeding unit 4, and the fed sheet P1 is temporarily stopped by the registration roller pair 71 and then fed at the same timing as the trial printing. The The sheet P1 is pressed against the third plate-making image 66A of the single-sided printing master 66 by the press roller 13, whereby an image corresponding to the third plate-making image 66A is printed on the surface.

  The sheet P1 on which the image is printed on the front surface passes through the upper surface of the switching member 10 occupying the first position 10a by actuating the solenoid 123, and is peeled from the single-sided printing master 66 by the peeling claw 84, and then discharged. It is conveyed by the member 85 and discharged onto the paper discharge tray 86.

  If the stop switch 105 is pressed and the door cover 120 is detected to be opened during the printing start and continuation process in step A5, the process proceeds from step A16 to step A17. Otherwise, normal printing is continued. Proceed to A8.

In step A17, it is determined whether or not the door cover 120 has been opened normally, for example, for opening the plate cylinder, etc., and in step A18, the error determination, for example, the control means 160 is not performed. If it is open in response to an error signal due to detection of out of paper, poor paper feed operation, etc., the process proceeds to step A19.
When step A19 is reached in response to an error, measures are taken to restore the normal state in response to the error, and then the door cover 120 is closed, and when the process returns to step A5, printing is resumed.

  In step A17, it is determined that the door cover 120 has been normally opened, and when step S18 is reached, detection of drum replacement and subsequent closing of the door cover 120 are awaited. That is, the plate cylinder unit 162 before replacement is fitted to the front and rear plate cylinder receiving frames 172 and 173 in the apparatus main body 11, and the plate cylinder unit 162 is taken out from the front and rear plate cylinder receiving frames 172 and 173. Thus, the main body side contact line J1 and the plate cylinder side contact line J2 are pulled out. After that, when a new plate cylinder unit 162 is fitted to the front and rear plate cylinder receiving frames 172 and 173, the control means 160 controls the plate cylinder before the main body side contact row J1 and the plate cylinder side contact row J2 are disconnected. The recognition signal of the new plate cylinder and the recognition signal of the new plate cylinder by reconnection are sequentially fetched. As a result, the control means 160 detects, as the plate cylinder connection detection means 220, that the plate cylinder 12 has been replaced by detecting the insertion / removal of the plate cylinder 12 into the plate cylinder mounting portion. Thereafter, when the closing of the door cover 120 is detected, the process proceeds to Step A20.

  In step A20, since the platemaking mode stored in the storage device in advance is the single-side platemaking mode (DFIG = 0) as determined in step A2, the master 64 wound around the plate cylinder replaced this time is used here. The point that the printing cannot be resumed is displayed on the display device 116 of the operation panel 103 without intentionally performing the processing in the above-described step A11 of detecting the type of the image by the rear end detection sensor 170 serving as the master detection means. For example, the message "Cannot continue printing as it is. Please review the original and the paper on the paper tray and make the plate again." And the control of this time is returned to enter a plate making standby state (a state of waiting for pressing of the enter key 106a).

  In this step A20, when a master made in the single-side plate making mode (DFIG = 0) is wound, if the plate cylinder is replaced, the master for double-sided printing 65 is wound. For example, the paper P supplied in the current single-side plate-making mode cannot be used, and it is necessary to reset the control again (press the enter key 106a). Further, if the single-sided printing master 66 is wound around the plate cylinder, the selection range of the appropriate paper P is large, and it is desirable to manually input the correspondence with the paper P in order to prevent the occurrence of defective printing. Again, since it is preferable to prompt the operator to return to the plate making and set the appropriate paper P appropriately, it is necessary to reset the control again (press the enter key 106a). From such a point, if the master made in the single-side plate making mode (DFIG = 0) is wound and there is a plate cylinder exchange, the processing like the above-described step A11 for detecting the type of the master is dared. Without being performed, the point that printing cannot be resumed is displayed on the display device 116 of the operation panel 103, and control can be performed by a program so that printing cannot be resumed. Appropriate printing is enabled by returning to the initial state again after the user recognizes and pressing the plate making button. Furthermore, in the case where the replaced drum is a master that has been subjected to separate plate making other than double-side plate making, it is possible to prevent the occurrence of a problem that the surface of the pressing means is soiled with ink by directly pressing the perforated portion with the pressing means. it can.

  As described above, the plate cylinder connection detecting means 220 is configured to intermittently connect the signal line connected to the control means 160 between the main body side contact line J1 and the plate cylinder side contact line J2, as shown in FIGS. However, the present invention is not limited to this. For example, as shown in FIG. 12, a photo sensor 230 is attached to a plate cylinder receiving frame 173 in the apparatus main body. The detection area of the photosensor 230 is formed so that the rear end 141 of the support shaft 14 of the plate cylinder unit 162 can be inserted. Accordingly, the plate cylinder connection detecting means 220 ′ for detecting the attachment / detachment of the plate cylinder unit 162 by inputting the detection signal of the photo sensor 230 to the control means 160 may be configured. The same effect as the means 220 can be obtained.

1 is a schematic front view of a double-sided printing apparatus to which the present invention is applied. It is an enlarged view which shows the structure of the refeed means used for the double-sided printing apparatus to which this invention was applied. It is an enlarged view which shows the structure of the contact / separation mechanism of the press means used for the double-sided printing apparatus to which this invention was applied. It is explanatory drawing of the master used for the double-sided printing apparatus to which this invention was applied, (a) shows the master for double-sided printing, (b) shows the master for single-sided printing. It is the schematic of the operation panel used for the double-sided printing apparatus to which this invention was applied. It is a block diagram of the control system used for the double-sided printing apparatus to which this invention was applied. FIG. 2 is an enlarged plan view of a plate cylinder unit used in a duplex printing apparatus to which the present invention is applied. The plate cylinder unit of FIG. 7 is shown, (a) shows a front view, and (b) shows a rear view. It is a flowchart of the plate making and plate-making process routine which the control system of the duplex printing apparatus to which this invention is applied performs. It is a flowchart of the plate making and plate-making process routine which the control system of the duplex printing apparatus to which this invention is applied performs. It is a flowchart of the printing process routine which the control system of the double-sided printing apparatus to which this invention was applied performs. It is a partial notch top view of the plate cylinder unit which shows the modification of the plate cylinder connection detection means used with the control system of the double-sided printing apparatus to which this invention was applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Double-sided printing apparatus 11 Apparatus main body 12 Plate cylinder 13 Pressing means (press roller)
14 Support axis 65 Master for duplex printing (split master)
65A First plate-making image 65B Second plate-making image 66 Master for single-sided printing (master-made master)
66A Third platemaking image 103 Operation panel 116 Display device 120 Front cover 160 Control means 162 Plate cylinder unit 163 RAM (storage device)
170 Master detection means (rear end detection sensor)
172 and 173 Plate cylinder receiving frames before and after 210 Door cover open / close detection sensor 220 Plate cylinder connection detection means P Paper

Claims (6)

A divided plate-making master having a plate cylinder and pressing means provided so as to be able to contact with and separate from the plate cylinder and having a first plate-making image and a second plate-making image in the length direction of the master at the time of double-side printing Double-sided printing in which a plate-making master on which a third plate-making image for single-sided printing has been formed is wound around the plate cylinder and subjected to a front surface printing process and then a back surface printing process. In a double-sided printing device capable of switching between single-sided printing and single-sided printing,
Master detection means for detecting the rear end of either the master-making master or the divided master-making master wound around the plate cylinder, and winding around the plate cylinder based on detection information from the master detection means Control means for determining the type of master being
When the plate making mode at that time is stored in the storage device based on the information that the plate making in at least one of the double-sided printing mode or the single-sided printing mode has been performed, and when the double-sided plate making is stored in the storage device When the plate cylinder is replaced, the type of master on the plate cylinder is detected by the master detection means, and printing restart is permitted when the master on the plate cylinder is made in the duplex printing mode. Otherwise, the double-sided printing apparatus is characterized in that printing cannot be resumed. The double-sided printing apparatus according to claim 1,
Display control means for displaying the state of the master on the operation panel, main body side contact row and plate cylinder side contact row for transmitting a recognition signal of the plate cylinder to the control means, and the printing drum to the apparatus main body Detecting means capable of detecting insertion / removal to the plate cylinder mounting portion to be mounted from an intermittent state of the main body side contact row and the plate cylinder side contact row ;
When the plate cylinder of the double-sided plate making for winding the master made in the double-sided printing mode is stopped in the middle of printing or waiting in a normal state where printing is possible, the above-mentioned insertion / removal is not performed. When detected by a detecting means capable of detecting and the master detecting means , the display control means displays on the operation panel that printing on the plate cylinder of the double-side plate making can be resumed. The double-sided printing apparatus according to claim 2,
When the printing is stopped due to error processing in accordance with an error signal during printing, a detection cylinder capable of detecting the insertion / removal and a plate cylinder of double-sided plate making to wind the master made in the double-sided printing mode by the master detection means A double-sided printing apparatus characterized in that when it is detected that it has been inserted again, it is considered that the same plate cylinder has been removed and inserted, and the same printing as before stopping is resumed. The double-sided printing apparatus according to claim 2,
When the printing cylinder is stopped in the middle of printing or waiting in a normal state where printing is possible, the plate cylinder is replaced and the type of master on the printing cylinder is detected by the master detection means, and the detected plate cylinder is detected. Printing is permitted only when the master plate-making mode and the plate-making mode written in the storage device are both-side plate-making. In other cases, the display control means displays that printing cannot be resumed. A double-sided printing device. The double-sided printing apparatus according to claim 4.
When printing can be resumed after replacing the plate cylinder, the display control means displays on the operation panel that printing can be resumed in the plate making mode before stoppage or standby. . The double-sided printing apparatus according to claim 4.
When resumption of printing is not permitted after the plate cylinder replacement, the display control means displays on the operation panel that printing cannot be resumed and it is necessary to make the plate again, and waits for the input of a plate making instruction again A double-sided printing apparatus, wherein

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