JP4758221B2 - Stencil printing machine - Google Patents

Description

  The present invention relates to a stencil printing apparatus that performs printing by directly or indirectly transferring an ink image to a printing medium while supplying ink to a master on a plate cylinder around which a master as a plate is wound, More specifically, the present invention relates to a master double winding detection device for a plate cylinder in a stencil printing apparatus.

  Conventionally, a heat-sensitive digital stencil printing apparatus is known as a simple printing method. This is a mixture of Japanese paper fiber and synthetic fiber, or Japanese paper and synthetic fiber on a plate cylinder made of a porous support cylinder and the like, and a thermoplastic resin film (hereinafter sometimes simply referred to as “film”). Using a master with a laminated structure bonded with a porous support made of, etc., the thermoplastic resin film surface of the master is heated, melted and punched with a thermal head arranged in the plate making section, and then wound around the plate cylinder, An appropriate amount of ink is supplied to the inner peripheral surface of the plate cylinder by an ink supply means provided inside the plate cylinder, and a printing paper (hereinafter referred to as “paper”) as a printing medium by a pressing means such as a press roller or an impression cylinder. Is directly or indirectly pressed against the outer peripheral surface of the plate cylinder to transfer and transfer the ink oozed from the plate cylinder opening portion and the master perforation portion to the paper for printing (for example, Patent reference 1).

Hereinafter, an example of the configuration and operation of the main part of a conventional stencil printing apparatus will be described with reference to the drawings. In the present specification, the plate cylinder is described in detail as being disposed on the outer peripheral portion of the printing drum. However, for the sake of simplicity, the plate cylinder is sometimes simply referred to as a printing drum. The master is a type of plate and is sometimes called stencil paper.
As schematically shown in FIG. 15 and FIG. 16, 2 is a printing drum having a plate cylinder around which a pre-made master 16 is wound, and 9 is substantially the same diameter as the outer diameter of the printing drum 2. , 160 is a stencil discharge unit for separating and discharging the used master 16 on the printing drum 2, 200 is a conventional stencil printing apparatus integrated with plate making, and 16e is a plate making completed. The rear ends of the master 16 are shown respectively.
In the plate removal unit 160, the plate release roller 61 and the plate discharge roller pair 62 have a function as plate release means for peeling and discharging the used master 16 on the printing drum 2, and rotate their shafts 61a, 63a, 64a. A plate discharging unit 65 is configured including freely supporting members and driving means. In FIG. 19, FIG. 21, FIG. 23, FIG. 24 and the like including FIG. 15, illustration of the upper plate discharge roller 63 constituting the plate discharge roller pair 62 is omitted as appropriate for simplification of the drawing.

  In the conventional stencil printing apparatus 200, when a used master 16 that is no longer necessary is wound around the printing drum 2, when making a new plate based on a new document, first, the used master 16 on the printing drum 2 is used. The printing drum 2 is rotated to the plate discharging position where the master 16 starts to be peeled off, temporarily stopped to enter the plate discharging standby state, and then the openable and closable clamper 4 disposed on the printing drum 2 is opened and held on the printing drum 2. The used master 16 that has been used is opened at its tip, and is rotated in the direction of the arrow in the drawing, which is disposed on the plate removal unit 160 and can swing between the position shown by the solid line and the position shown by the two-dot chain line in FIG. The upper end portion of the used master 16 is peeled off from the printing drum 2 by the discharged plate peeling roller 61, and then is composed of an upper discharged plate roller 63 and a lower discharged roller 64 that are pressed against each other and rotated in the direction of the arrows in the figure. The used master 16 conveyed to the plate discharging box 67 while being nipped and wound by the pair of plate discharging rollers 62 is transferred between the position indicated by the solid line and the position indicated by the two-dot chain line in FIG. The plate is compressed and stored in the discharge box 67 by the swingable compression plate 66.

At this time, the used master 16 is removed by a plate removal sensor 68 comprising a reflection type photosensor (reflection type optical sensor) having a light emitting element and a light receiving element attached at the positions shown in FIGS. It is detected whether the discharge roller pair 62 has been entered. The plate removal sensor 68 has a function as a plate removal master presence / absence detection means for detecting whether or not the used master 16 peeled off by the plate release peeling roller 61 is in the plate discharge roller pair 62. In addition, the part where the discharged plate sensor 68 detects whether or not the used master 16 has actually passed is a leading edge margin with as little ink adhesion as possible in order to prevent erroneous detection (FIG. 6A showing an embodiment described later). (B)), it is attached to the apparatus main body side so as to detect the part. The control means (not shown) monitors the voltage level output from the discharge plate sensor 68 within a time determined almost simultaneously with the timing at which the discharge roller pair 62 starts to move, and once it exceeds the preset reference voltage even once, It is determined that the used master 16 has entered the discharge roller pair 62. In other words, if the used master 16 passes normally over the discharge sensor 68 between the discharge roller pair 62, the ON detection is performed by the discharge sensor 68. Thus, it is determined that there is a master, and control is shifted to the next plate making operation.
When the used master 16 is normally peeled off from the printing drum 2 by the plate discharging unit 65, as shown in FIG. 19, it is transported into the plate discharging box 67 while being wound around the plate discharging roller pair 62, and then compressed. A series of plate removal operations of being compressed by the plate 66 is performed.

  If the voltage output from the plate ejection sensor 68 does not exceed the reference voltage even once in time, the used master 16 enters the plate ejection roller pair 62 as shown in FIGS. If not, it is judged by a control means (not shown), and a warning command for an error in removing the removed plate is issued to stop the machine operation. 20A and 20B, reference numeral 39 denotes a drum as a master presence / absence detecting means for detecting whether or not the master 16 is wound around the printing drum 2 when the printing drum 2 occupies the home position. Indicates a master presence / absence sensor. At this time, the drum master presence / absence sensor 39 remains on because it detects the presence of the used master 16 on the printing drum 2.

The home position as the initial position of the printing drum 2 refers to the rotational position of the printing drum 2 where the clamper 4 is located almost directly below. Here, the drum master presence / absence sensor 39 will be described in more detail with reference to FIG. 1 and FIGS. 6 (a) and 6 (b) showing embodiments to be described later. The drum master presence / absence sensor 39 includes a light emitting element and a light receiving element. The master 16 is wound around the printing drum 2 by detecting the presence or absence of the leading edge 16b of the master 16 on the printing drum 2 in a stopped state where the printing drum 2 is at the home position. It is a well-known thing which detects whether it is equipped.
A sensor as a light absorbing member is usually provided on the outer peripheral surface of the leading margin 16b of the master 16 wound around the printing drum 2 so that the drum master presence / absence sensor 39 can accurately detect the presence / absence of the master 16 on the printing drum 2. A sheet-like black mylar (PET) made of a light non-reflective material, also called a pattern, is disposed.

Japanese Patent No. 3332267

However, as shown in FIGS. 20B and 21, the used master 16 once enters the arrangement portion of the plate ejection sensor 68, and the output voltage from the plate ejection sensor 68 becomes equal to or higher than the reference voltage. After that, when the used master 16 that has reached the plate removal sensor 68 part has come out of the plate discharge roller pair 62 and the plate release roller 61 part, the used master 16 is actually discharged normally. In spite of the absence, it is erroneously determined that the normal plate removal operation is being performed, and the process proceeds to the next plate supply operation as shown in FIGS. Also at this time, the drum master presence / absence sensor 39 remains on because it detects the presence of the used master 16 on the printing drum 2.
In FIG. 20B, the used master 16 is detected in the discharged roller pair 62 if the discharged plate sensor 68 detects that the margin of the leading edge of the used master 16 is ON and exceeds a preset reference voltage even once. The reason why it is judged that the normal peeling / discharge plate has entered normally is that the behavior of the used master 16 to which the ink has been attached during the peeling / discharge plate winding and conveyance is unstable and complicated. A predetermined time required for discharging the plate is simply set in advance from the rotation speed of the printing drum 2 and the master size when the discharging plate is wound and transferred by the discharging roller pair 62, and the tip of the used master 16 of the discharging sensor 68 is set. This is based on the fact that it is not determined by the time measurement from the on detection to the off detection of the rear end.

  In such a case, even though the used master 16 remains on the printing drum due to a peeling error and remains as a residual master 16B, it is newly made by the plate making unit 15 from there. Double winding in which the master 16 is wound around the printing drum 2 occurs (see FIG. 24). In FIG. 24, the clamper 4 is not shown. When printing is performed in the master double winding state, as shown in FIG. 25, application and supply to the inner peripheral surface of the printing drum 2 by the ink roller 6 constituting the ink supply device 5 disposed in the printing drum 2. Since there is a portion in which the ink that has not been oozed out from the opening portion of the plate cylinder 2A in the printing drum 2 to the new master 16 that has been made, a blank plate making or an abnormal image (a part of the ink oozes on the paper S) occurs. This causes waste of supplies such as paper S and ink and waste of user work time. Here, “white paper plate making” means that no ink is transferred to the paper S.

  In the plate feeding operation shown in FIG. 22, the master 16 made by the plate making unit 15 is temporarily stopped at the plate feeding position, that is, the plate drum is waiting for the printing drum 2 constituting the drum unit 13, ie, the plate 16 is expanded. After the leading end of the master plate 16 has been locked by the closing operation of the clamper 4, the outer periphery of the printing drum 2 is rotated by the rotation of the printing drum 2 in the direction of the arrow in FIG. An operation of being wound around the surface (the outer peripheral surface of the plate cylinder) is performed.

  As described above, in the stencil printing apparatus described in Japanese Patent No. 3332267 (Patent Document 1), the stencil conveying roller pair (65) shown in FIG. 1 and FIG. Of course, it has a transmissive stencil sensor (69) that detects the presence or absence of the stencil sheet (S), but it cannot of course detect the double winding of the master. It was not possible to eliminate waste of supplies such as paper and ink and waste of user's work time.

The present invention has been made in view of the above-described circumstances, and a master removal detection means detects a master removal from a plate removal means during the removal and removal of a used master on a plate cylinder, thereby removing a plate removal peeling. The first object is to reliably detect the above (claim 1).
When the master missing detection means detects a removal error (the master missing), the printing operation is prohibited and a warning to that effect is issued to minimize the waste of supplies such as paper and ink. In addition, a second object is to eliminate the waste of the user's work time (claim 3).

The used master on the plate cylinder due to a mistake in removing the plate is detected by detecting the presence of the used master remaining on the plate cylinder due to the peeling or defective printing of the used master by the plate removing means. The third object is to reliably detect the remainder of the master (claim 4).
When the master remaining presence detection means detects a used master remaining on the plate cylinder due to an error in peeling and exfoliating the master (the above-mentioned master missing), the printing operation is prohibited and a warning to that effect is given to the user. Accordingly, the fourth object is to minimize the waste of the supply of paper, ink and the like and to save the user's work time.

In order to solve the problems and achieve the object, the invention according to each claim employs the following characteristic means and configuration.
According to the first aspect of the present invention, a plate cylinder around which a pre-printed master is wound, a plate discharging means for peeling and discharging a used master on the plate cylinder, and a pre-made master is fed to the plate cylinder. In the stencil printing apparatus, comprising: a plate supplying unit that performs a plate supplying operation; and a printing unit that performs a printing operation by directly or indirectly pressing a printing medium on a master plate on the plate cylinder. And a master removal detecting means for detecting the removal of the used master from the plate removal means when the used master is peeled off and discharged.

  According to a second aspect of the present invention, in the stencil printing apparatus according to the first aspect, the master missing detection means is disposed on a used master discharging path between the plate cylinder and the plate discharging means. It is characterized by.

  According to a third aspect of the present invention, in the stencil printing apparatus according to the first or second aspect of the invention, the stencil feeding unit performs the stencil feeding unit based on an output signal from the first notifying unit for notifying information and the master missing detection unit. After finishing the plate feeding operation, the printing means is used to prohibit the printing operation, and the first notifying means is used to notify that the used master is removed from the plate discharging means. Control means.

  According to a fourth aspect of the present invention, in the stencil printing apparatus according to any one of the first to third aspects, the used master remaining on the plate cylinder without being peeled or discharged by the plate discharging means. It has a master remaining presence / absence detecting means for detecting presence / absence.

  According to a fifth aspect of the present invention, in the stencil printing apparatus according to the fourth aspect, the remaining master detection means remains on the plate cylinder in a state where the plate cylinder occupies a predetermined feeding position. It is characterized in that it is arranged at a position where the rear end margin of the used master can be detected.

  According to a sixth aspect of the present invention, in the stencil printing apparatus according to any one of the third to sixth aspects, the second informing means for informing information and an output signal from the master remaining presence detecting means. After the plate feeding operation is finished by using the plate feeding means, the printing means is used to prohibit the printing operation, and the second notification means is used to remain on the plate cylinder. And a second control means for notifying that there is a completed master.

According to the present invention, it is possible to provide a novel stencil printing apparatus by solving the above-described problems of the prior art. The effects of each claim are as follows.
According to the first aspect of the present invention, the master removal detecting means for detecting the removal of the used master from the plate removal means when the used master is peeled or discharged by the plate removal means is provided. Since it is possible to detect the removal from the plate discharging means, that is, the return to the plate cylinder side, it is possible to determine the contents of the plate release peeling error.

  According to the second aspect of the present invention, the master missing detection means is arranged on the used master discharging path between the plate cylinder and the discharging means. (Return to the trunk side) can be reliably detected.

  According to a third aspect of the present invention, the first control means uses the printing means to finish the plate feeding operation based on the output signal from the master missing detection means, and then performs printing using the printing means. The operation is prohibited and the first notification means is used to notify that the used master has come out of the plate discharging means (master double winding occurrence), so that damage to the machine is avoided, and the plate cylinder is the main body of the apparatus. When the plate cylinder unit is detachable from the apparatus, the user can remove the plate cylinder unit from the apparatus main body or open the open / close door that is appropriately disposed. By exposing the part and facilitating the user's post-processing (double winding master processing) and not performing printing operations, waste of supplies such as paper and ink can be minimized, and the user can It is possible to eliminate the waste of work time.

  According to the invention described in claim 4, in addition to being able to detect the removal of the used master from the plate discharging means (returning to the plate cylinder side) by the master removal detecting means, the master is removed and discharged by the plate discharging means. Without remaining master detection means for detecting the presence of a used master remaining on the plate cylinder, it is possible to detect the presence or absence of a used master remaining on the plate cylinder due to a plate removal error. At the same time, by performing detection at the time of peeling / discarding and at the plate feeding position, it becomes possible to discriminate a total of two plate peeling errors during one feeding / discharging operation.

  According to the fifth aspect of the present invention, the remaining master detection means detects the trailing edge margin of the used master remaining on the plate cylinder in a state where the plate cylinder occupies a predetermined plate feeding position. By being arranged in a detectable position, it is possible to reliably detect the presence or absence of a used master remaining on the plate cylinder.

  According to the sixth aspect of the invention, in addition to the effect of the third aspect of the invention, the second control means performs the plate feeding means based on the output signal from the master remaining presence / absence detecting means. After finishing the operation, the printing means is prohibited to prohibit the printing operation, and the second informing means is used to indicate that there is a used master remaining on the plate cylinder (occurrence of master double winding). In order to avoid damage to the machine, if the plate cylinder forms a detachable plate cylinder unit with respect to the apparatus main body, the user can remove the plate cylinder unit from the apparatus main body or By opening the open / close doors, etc., the processing target is exposed to facilitate post-processing of the user (processing of the double winding master), and by performing no printing operation, Waste of supplies such as ink It is possible to minimize, it is possible to eliminate the waste of work time of the user.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention including examples will be described with reference to the drawings. The constituent elements (members and constituent parts) having the same function and shape throughout the background art and the embodiments described above, etc., once described, are denoted by the same reference numerals, and the description thereof is omitted. In the figure, components that are configured in a pair and do not need to be specifically distinguished and described are described by appropriately describing one of them for the sake of simplification of description. In order to simplify the drawings and the description, even if the components are to be represented in the drawings, the components that do not need to be specifically described in the drawings may be omitted as appropriate. When quoting and explaining constituent elements such as published patent gazettes, the reference numerals are shown in parentheses to distinguish them from those of the embodiments.

An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows the overall configuration of a stencil printing apparatus 1 to which the present invention is applied. In FIG. 1, reference numeral 1 </ b> A denotes a main body frame as an apparatus main body that forms the framework of the stencil printing apparatus 1.

  The stencil printing apparatus 1 includes a document reading unit 70 that reads an image of a document 73 (not shown) placed on a contact glass 74 or a document 73 that is placed on the main body frame 1A and transferred from a document placement table 72, and the document. A plate making unit 15 that is disposed on one side of the main body frame 1A below the reading unit 70 and punches the master 16 that is fed from a master roll 16A wound around the core tube in a roll shape, and the main body frame 1A. The printing drum 2 having a plate cylinder wound around the outer peripheral surface of the master 16 that has been perforated and made in the center of the plate, and the lower side of the printing drum 2 is fed. In addition, a paper holding clamper 12 is provided as a holding means for holding and holding the leading end portion of the paper S as an example of the printing medium, and the paper S is placed on the master 16 already made on the printing drum 2. A printing unit 14 having an impression cylinder 9 to be pressed, a paper feeding unit 50 that is disposed below the plate making unit 15 and that stacks sheets S stacked on the paper feeding tray 51 to the printing unit 14, and faces the paper feeding unit 50 A paper discharge unit 90 that is disposed below the main body frame 1A and that has been printed by the printing unit 14 is discharged to a paper discharge tray 91, and is disposed between the paper discharge unit 90 and the document reading unit 70. Then, the used master 16 is peeled off from the outer peripheral surface of the printing drum 2 and the plate discharging unit 60 that discharges and discharges the master 16 into the plate discharging box 69 and the respective units and devices of the stencil printing apparatus 1 are instructed to perform desired operations. An operation panel 100 for performing operations to be performed, and a control device 130 that is disposed between the plate making unit 15 and the paper feeding unit 50 and controls the operation of the entire stencil printing apparatus 1 are provided.

Hereinafter, the document reading unit 70, the plate making unit 15, the printing unit 14, the paper feeding unit 50, the plate discharging unit 60, the paper discharge unit 90, and the control device 130 will be described. The plate making unit 15 supplies the master 16 to the printing drum 2. It has a part of the configuration of the plate supplying means for performing the plate supplying operation, and is also called a plotter unit or a plate making plate supplying device. Similarly, the printing unit 14 has a part of the configuration of the plate supplying means. Details of the plate supplying means will be described later.
The stencil printing apparatus 1 is provided at a predetermined position shown in FIG. 1 and the like in that the stencil printing apparatus 1 has a master drop detection sensor 35 disposed at a predetermined position shown in FIG. The main difference is that it has a remaining master detection sensor 30 and a control device 130 that performs specific control described later based on output signals from the master missing detection sensor 35 and the master remaining detection sensor 30. As such, other known configurations are only briefly described.

  The document reading unit 70 separates the document placing table 72 on which a plurality of documents 73 are stacked, the contact glass 74 as a reading unit on which the document 73 is placed, and the document separation for separating and transporting the documents 73 one by one. A roller 75, a document transport roller group 76 for transporting and discharging the separated document 73, and a fixed image reading means for reading an image of the transported document 73 with a contact glass 78 as a reading unit. CIS (contact image sensor) 77, a document discharge stand 79 on which the read document 73 is loaded, and the members excluding the contact glasses 74 and 78 are supported and contacted and separated from the contact glasses 74 and 78. Scanning is performed with a pressure plate 80 that can be freely opened and closed, reflection mirrors 81, 82a, and 82b, and a fluorescent lamp 83 for scanning and reading an image of the original 73 while illuminating it. A lens 84 for focusing the reflected light image read, and a like image sensor 85 having a CCD (charge coupled device) or the like for processing the reflected light of the focused image.

In the configuration described above, automatic document feeding is performed in which the document 73 is fed one by one onto the contact glass 78 (reading unit) by the document placing table 72, the document separation roller 75, the document conveying roller group 76, the CIS 77, and the document discharge table 79. An automatic document feeder (hereinafter referred to as “ADF”) 71 as a feeding means is configured. The document separation roller 75 and the document transport roller group 76 are driven by a driving motor connected via a known driving force transmission means. A scanner 87 serving as a document reading unit that reads an image of the document 73 on the contact glass 74 (reading unit) by the contact glass 74, the reflecting mirrors 81, 82a, and 82b, the fluorescent lamp 83, the lens 84, and the image sensor 85 is provided. It is configured. The drive components of the scanner 87 are driven by a scanner drive motor connected via known drive force transmission means.
The CIS 77 and the image sensor 85 perform photoelectric conversion in response to the received reflected light, and an analog image signal obtained thereby is analog / digital (not shown) in the main body frame 1A (hereinafter abbreviated as “A / D”). The data is input to the conversion unit, and is input from the A / D conversion unit to the plate making control unit (not shown) via an image processing unit having an image area memory (not shown).
The digital image signal transmitted to the image processing unit may be input to the control device 130 via a PC (personal computer) controller from a network (not shown) configured to be communicably connected to the stencil printing apparatus 1. is there.

As shown in FIG. 1, the plate making unit 15 has substantially the same configuration as that of the plate making apparatus (15) described in, for example, Japanese Patent Application Laid-Open No. 2004-9642. .
The plate making unit 15 includes a master support member 17 that stores the master 16 from the master roll 16A so that the master 16 can be fed out, a master set guide plate (not shown) for placing the tip of the master 16 that is fed out from the master roll 16A, and A master set roller 19 that contacts the master set guide plate via the tip of the master 16 and conveys the master 16, and a thermal head as a plate making means for making a heat sensitive plate according to an image signal from the master 16 fed from the master roll 16A. 22, a platen roller 23 that rotates and conveys the master 16 against the thermal head 22, a platen pressure release mechanism (not shown) that contacts and separates the thermal head 22 from the platen roller 23, a tension roller pair 25, As a cutting means to cut the master 16 that has not yet been made And a reversing roller pair 28, and a master storage means 27 that temporarily stores the master 16 that has been subjected to plate making, including a bending box (not shown), a guide conveying plate (not shown), and the like. ing.

The thermal head 22 has a plurality of heating elements arranged along the main scanning direction corresponding to the axial direction of the platen roller 23, and passes through the A / D conversion unit and the image processing unit of the document reading unit 70. Based on the digital image signal processed and sent out by the plate making control unit or the like, the film portion of the master 16 corresponding to the heat generation position by selectively heating the heat generation element by selective energization control to the heat generation element Are melted by heating and drilled.
The platen roller 23 is rotated by a plotter motor 24 composed of a stepping motor connected through a known rotation transmission means, and presses the master 16 against the thermal head 22 while the tension roller pair 25 on the downstream side in the master transport direction, the master It is conveyed to the storage means 27.

The cutter unit 26 is a known unit that cuts the master 16 by moving in the master width direction orthogonal to the master transport direction. For example, the cutting shown in FIGS. 2 to 5 of Japanese Patent Laid-Open No. 2000-6510 It is the same as the means (4).
The master storage means 27 is, for example, the same as the master storage means (30) described in Japanese Patent Application Laid-Open No. 2003-118221, a three-stage switching deflection box (32), a guide transport plate (31), and a transport plate drive (not shown). Main solenoids, suction fans (34a, 34b), and remaining master detection sensors (36a-36d).

  The reverse roller pair 28 is configured such that the upper roller is a drive roller and the lower roller is a driven roller. The reversing roller pair 28 has a function as a plate feeding unit that feeds the master 16 having been subjected to plate making stored in the master storage unit 27 to the clamper 4 of the printing drum 2. The reversing roller 28 as an upper driving roller is connected to a reversing roller stepping motor 29 (hereinafter referred to as “stepping motor 29”) driven by a pulse input different from the plotter motor 24 through a known rotation transmission means. Has been. The master conveyance speed by the reverse roller pair 28 is set in advance so as to be slightly higher than the master conveyance speed by the platen roller 23.

  Any known master 16 can be used. That is, for example, as described in Japanese Patent Application Laid-Open No. 10-147075, it is possible to reduce the image quality deterioration due to the fiber pattern while the ink adhesion amount is relatively small, the printing unevenness is small, the back stain of the printed matter is small. Have a laminate structure in which a master, for example, a polyethylene terephthalate (PET) film, and a support made of Japanese paper fiber or synthetic fiber, or a mixture of Japanese paper and synthetic fiber are bonded together with an adhesive However, the thickness of a conventional master (specifically, for example, polyethylene terephthalate (PET) film or the like is about 1 to 5 μm, the thickness of the support is about 45 to 55 μm, and the total thickness is 50 Compared to those having a thickness of about 60 μm), the thickness is relatively thin and the strength is low ( Speaking physically, for example, the film structure is the same, and the thickness of the support is about 25 to 30 μm, and the total thickness is about 30 to 35 μm), or a conventional master with a thick total thickness is used. It can be used.

As shown in FIGS. 1 and 2, the printing unit 14 has a function and configuration as a printing unit that performs a printing operation by directly pressing the paper S against the master 16 on the printing drum 2. That is, as shown in FIG. 1, the printing unit 14 is the same as the printing pressure device (14) described in JP-A-2003-118221, and has the same printing drum 2 and the peripheral speed of the printing drum 2. Ink is applied to a pressure drum 9 as a pressing means that rotates at a peripheral speed and in a predetermined synchronization with the plate cylinder 1, and to a master 16 that is disposed inside the printing drum 2 and is made on the printing drum 2. It has well-known components such as an ink supply pipe 3 for supplying ink to the ink reservoir 8, an ink supply device 5 composed of an ink roller 6 and a doctor roller 7, and the like. As the ink, a W / O type emulsion ink is preferably used, but it is needless to say that the ink is not limited thereto. As the pressing means, a known press roller smaller than the diameter of the printing drum 2 may be used in addition to the pressure drum 9 having substantially the same diameter as the printing drum 2.
1 and 2, reference numeral 38 denotes a nurse roller as an ink replenishing roller similar to that disclosed in, for example, Japanese Patent Laid-Open No. 11-180026.

  The printing drum 2 has a support cylinder having a large number of ink-permeable apertures 2a and a multi-layer mesh screen (not shown) wound around the outer peripheral surface thereof. It is rotatably supported. As shown in FIG. 2, the printing drum 2 is formed with a printable area in which an opening 2a is formed over a predetermined range on the circumference excluding the periphery of the clamper 4 and the stage portion arrangement portion, and the opening 2a. A non-ink-impermeable non-printing area is formed. The printing drum 2 includes a main motor 40 connected via a driving force transmission means such as a gear train and a belt (not shown) so that the rotation speed can be changed corresponding to a plurality of printing speeds. Is rotated through. The main motor 40 is a DC motor that can be rotated forward and backward.

  In the printing drum 2, a clamper 4 as a holding means for holding and fixing the front end portion of the master 16 that has been subjected to plate making is disposed along a generatrix of the outer peripheral portion of the printing drum 2. The clamper 4 is pivotally attached to the outer peripheral portion of the printing drum 2 with a clamper shaft that is rotatable by a predetermined angle, and can swing and open / close. The clamper 4 has a rubber magnet, and when the printing drum 2 occupies a plate discharging position or a plate feeding position, which will be described later, and temporarily stops, for example, in FIGS. 1 to 7 of JP-A-6-247031. It is opened and closed with respect to the stage part which consists of a ferromagnetic material provided in the outer peripheral part of the printing drum 2 with the opening / closing apparatus which comprises the structure similar to the base paper latching apparatus (60) shown.

  As shown in FIG. 2, a pulse encoder 44 that detects the rotation amount (rotation angle) of the printing drum 2 is disposed on the main motor 40 side. The pulse encoder 44 is fixed to an incremental type photo-rotary encoder 45 fixed to the output shaft 40a of the main motor 40 and the main body frame 1A in the vicinity of the photo-rotary encoder 45, and the photo-rotary encoder 45 is clamped at a predetermined interval. And an encoder sensor 46 composed of a transmissive photosensor (transmissive optical sensor). The encoder sensor 46 detects a predetermined number of pulses generated in cooperation with the rotary operation of the photo rotary encoder 45 by the rotation drive of the main motor 40, thereby detecting the rotation amount and rotation speed of the printing drum 2. It is like that. Thereby, the rotation amount and rotation speed of the printing drum 2 are controlled via the main motor 40.

  As shown in FIG. 2, the end plate on the back side in the drawing of the printing drum 2 is substantially “「 ”in a front view protruding to the back side of the paper surface of the printing drum 2 for detecting and indexing the rotational position of the printing drum 2. A light-shielding piece 41 having a letter shape is fixed. On the other hand, at a predetermined position on the main body frame 1 </ b> A side facing the end plate on the back side in FIG. 2 of the printing drum 2, a home position as an initial position where the printing drum 2 positions the clamper 4 almost directly below the printing drum 2. , The home position sensor 42 as an initial position detecting means for detecting the home position by engaging with the light-shielding piece 41, and the print drum 2 moves the clamper 4 to the right side of the print drum 2. A plate feeding position sensor 43 serving as a plate feeding position detecting means for detecting the plate feeding position by engaging with the light shielding piece 41 when the plate feeding position located obliquely upward to the right is occupied. ing. The home position sensor 42 and the plate feeding position sensor 43 are transmissive photosensors.

The detection of the plate discharging position where the printing drum 2 positions its clamper 4 substantially diagonally to the left of the printing drum 2 is based on the signal related to the home position from the home position sensor 42 and the rotation amount of the printing drum 2 from the encoder sensor 46. Based on such a signal, the control device 130 calculates and obtains it.
Hereinafter, the state where the printing drum 2 is stopped at the plate feeding position may be referred to as “plate feeding standby position”, and the state where the printing drum 2 is stopped at the plate discharging position may be referred to as “plate discharging standby position”.

As shown in FIGS. 18 and 22, for example, the printing drum 2 is similar to the plate cylinder device (55) shown in FIGS. 2 and 3 of JP-A-5-229243. In addition, a drum unit 13 is formed as a unit. That is, as shown in FIGS. 18 and 22, the drum unit 13 includes a printing drum 2 in which the ink supply device 5 is disposed, a support shaft 3 also serving as an ink supply tube, and a long plate-shaped gripping frame 13A. A rear frame and a front frame (not shown), which are respectively suspended from both ends of the printer, and rotatably support the printing drum 2 via the support shaft 3, an ink pump device and an ink device piping part (both not shown), etc. It comprises.
The drum unit 13 is attached to the main body frame 1A through attachment / detachment means provided on the main body frame 1A side having the same configuration as the holding means (36) shown in FIG. On the other hand, it is detachable.

  A plate feeding unit (plate feeding device) as a plate feeding unit for feeding the master 16 after plate making to the printing drum 2 includes a pair of reversing rollers 28 in the plate making unit, a stepping motor 29, a printing drum 2 provided with a clamper 4, and a clamper. 4 is mainly composed of the opening / closing device for opening and closing 4 and the main motor 40.

  As shown in FIG. 1, the paper feed unit 50 includes a paper feed tray 51 as a paper feed tray on which the paper S is stacked, a paper feed roller 52 that feeds and feeds the uppermost paper S on the paper feed tray 51, A separation roller 53 and a separation member 54 for separating the paper S fed out by the paper feeding roller 52 one by one, a guide plate for guiding the paper S in the paper transport direction, and a single separated paper S are expanded. A pair of registration rollers 55 that are transported in a timely manner to the paper holding clamper 12, and a pair of side fences 56 that are movable in the paper width direction orthogonal to the paper transport direction and align both side edges of the paper S; It is mainly composed of a tray lifting / lowering motor (not shown) that lifts and lowers the paper feed tray 51 in conjunction with the increase / decrease of the paper S stacked on the paper feed tray 51.

The separation roller 53 and the paper feed roller 52 are in a rotational driving force transmission relationship via a known rotational driving force transmission means, and the separation roller 53 is a feeding motor comprising a stepping motor via a known rotational driving force transmission means. The paper motor 57 is connected. Therefore, the separation roller 53, the paper feed roller 52, and the paper feed motor 57 are in a rotational driving force transmission relationship through the rotational driving force transmission means.
The lower registration roller 55 is connected to a registration motor 58 formed of a stepping motor via a known rotational driving force transmission unit.

  As shown in FIG. 1, the paper discharge unit 90 is a printed paper that has been released from the paper holding clamper 12 by the operation of opening the paper discharge tray 91 and the paper holding clamper 12 as a paper discharge tray on which printed paper S is stacked. A paper discharge claw (not shown) for peeling and guiding the paper S, and a suction discharge outlet roller 93 and a suction discharge outlet roller 94 are spanned, and have an endless belt shape having a plurality of openings on the surface. A conveyor belt 95 and a fan motor are incorporated, and a rotation thereof generates a downward air flow in the figure, and a suction fan 96 that sucks the printed paper S on the surface of the conveyor belt 95, and a discharge fan that rotationally drives the conveyor belt 95. It is mainly composed of a paper drive motor (not shown). In FIG. 1, reference numeral 97 denotes an end fence that can move in the paper conveyance direction and aligns the leading edge of the printed paper S, and 98 denotes a paper that can move in the paper width direction and that is positioned at both ends of the printed paper S. A pair of side fences for aligning, 99 indicates a peeling fan with a built-in fan motor for separating and assisting the printed paper S from the master 16 on the printing drum 2 by blowing. .

  As shown in FIGS. 1 to 5, the plate discharging unit 60 includes a plate discharging unit 65 as a plate discharging means for peeling and discharging the used master 16 on the printing drum 2, and a used plate that has been peeled and discharged by the plate discharging unit 65. As shown in FIG. 15 and FIG. 16, etc., a plate discharge box 67 as a plate discharge storage means for storing the master 16, a compression plate 66 as a compression means for compressing the used master 16 discharged into the plate discharge box 67. A master removal sensor 68 serving as a master removal detection means for detecting that the used master 16 is removed from the plate removal unit 65 when the used master 16 is peeled off and removed by the plate removal unit 65 and the conventional plate removal sensor 68. It is equipped with.

The plate discharge unit 65 is a plate discharge roller 61 that peels the used master 16 on the printing drum 2 and a plate discharge that discharges and conveys the used master 16 peeled off by the plate release roller 61 to the plate release box 67 while winding it up. A conveyance roller pair 62 is included.
As shown in FIGS. 1 and 2, the discharge plate peeling roller 61 is configured to be swingable between a peeling position indicated by a two-dot chain line and a separation position indicated by a solid line. A plate discharge side plate (not shown) that swings the plate discharge peeling roller 61 between a peeling position and a separation position is disposed on a plate discharging side plate (not shown) fixed to the main body frame 1A side. When the printing drum 2 enters the standby state where the printing drum 2 is temporarily stopped at the discharging position, the discharging plate peeling roller 61 is oscillated and displaced so as to occupy the peeling position by the discharging plate swinging means.
The discharged plate peeling roller 61 is a member having a wheel shape that has high frictional resistance against the used master 16 to which ink such as nitrile rubber or chloroprene rubber has adhered and that has ink corrosion resistance (oil resistance). The center portion of the shaft 61a is fixed to the shaft 61a, and a plurality of shafts 61a are arranged in the master width direction. The shaft 61a is rotationally driven by a peeling roller driving motor 47, whereby the discharged plate peeling roller 61 is integrally rotated clockwise in both drawings.

  The pair of discharge plate conveying rollers 62 has a plate discharge roller upper 63 as a driven roller disposed on the upper side in both drawings and a plate discharge roller lower 64 as a drive roller disposed on the lower side, and each pair forms a pair. A plurality of them are arranged in the master width direction. The center of the upper plate discharging roller 63 and the lower discharging roller 64 is fixed to the shafts 63a and 64a, respectively. A shaft 64 a on the drive roller side of the lower plate discharge roller 64 is connected to a plate discharge conveyance motor 48 including a stepping motor via a known rotational drive transmission means, and is driven to rotate by the plate discharge conveyance motor 48. By this discharge plate conveying motor 48, the lower discharge roller 64 is driven to rotate counterclockwise in both drawings, and the upper discharge roller 63 is driven to rotate clockwise in both drawings. The rotational speed of the discharge plate conveying motor 48 is controlled so that the rotational peripheral speed of the lower plate roller 64 is higher than the peripheral speed of the printing drum 2 at the time of discharging.

  The master omission detection sensor 35 is unique to the present embodiment. As shown in FIGS. 1 to 3, as shown in FIGS. 1 to 3, the entrance of the plate discharge unit 65 closer to the print drum 2 than the installation position of the plate release sensor 68, that is, the print drum. 2 and the discharging unit 65 are disposed on the discharging path (indicated by a thick solid line) of the used master 16.

  As shown in detail in FIGS. 4 and 5, the master removal detection sensor 35 includes a filler 34 as a light shielding piece that is movable only in the plate discharge return direction Xb, which is the removal direction of the used master 16 from the plate discharge unit 65. It consists of a transmissive photosensor. Such a transmission type photosensor with the filler 34 is general-purpose. As shown in FIGS. 5A to 5D, the master missing detection sensor 35 includes a light emitting element 36 made of a light emitting diode and a light receiving element 37 made of a phototransistor as sensor internal circuits.

As shown in FIGS. 4B, 5A, and 5B, the filler 34 comes into contact with the used master 16 that is about to return from the discharging unit 65 and return to the discharging plate return direction Xb. The light 36 a generated by the light emitting element 36 passes through without being blocked by the filler 34 and is received by the light receiving element 37 in accordance with the tilting operation in which the 34 is tilted. Is output to the control device 130. In other words, when the master 16 that has come out of the plate discharge unit 65 and returned to the printing drum 2 side that has stopped or started to rotate in the clockwise direction is returned to the printing drum 2 side, the plate discharge path in the plate return direction Xb in which the filler 34 falls down. By disposing the master missing detection sensor 35 on the upper side, it is possible to detect that a plate removal error has occurred and that the used master 16 has been returned to the printing drum 2.
On the contrary, as shown in FIGS. 4A, 5C, and 5D, the filler 34 is normally peeled and conveyed in the plate discharge direction Xa by the plate discharge unit 65, including during the non-plate release operation. When it does not fall down due to contact with the used master 16, the light 36 a emitted from the light emitting element 36 is shielded by the filler 34, so that an off signal is electrically output from the master missing detection sensor 35. To the control device 130.

Next, with reference to FIGS. 1, 2 and 6 to 10, the master remaining detection sensor 30 having a configuration unique to the present embodiment will be described.
The remaining master detection sensor 30 has a function as remaining master detection means for detecting the presence or absence of the used master 16B remaining on the printing drum 2 without being peeled or discharged by the discharging unit 65. Here, the used master 16B (hereinafter referred to as “residual master 16B”) remaining on the printing drum 2 without being peeled or discharged by the plate discharge unit 65 is referred to as FIG. 4B and FIG. ), As shown in (b), it means that the used master 16 comes out of the plate discharge unit 65, returns to the plate return direction Xb, and is wound on the printing drum 2 again. .
As shown in FIG. 9, the master remaining detection sensor 30 is a general-purpose reflective photosensor including a light emitting element 31 made of a light emitting diode and a light receiving element 32 made of a phototransistor as sensor internal circuits.

  As shown in FIGS. 6 (a), 6 (b) to 8, the details of the master 16 that has been made on the printing drum 2 or the master 16 that has been used are as follows. It is divided into a leading edge margin portion 16b, a plate-making image region 16c shown by hatching, a trailing edge margin portion 16d which is an unmade region, and a trailing edge 16e. The leading edge 16a, leading edge blank portion 16b, trailing edge margin portion 16d and trailing edge 16e except for the image area 16c in the master 16 are located in the non-printing area of the printing drum 2, and are areas / areas where ink hardly adheres. .

As shown in FIGS. 6A and 7, the remaining master detection sensor 30 is in a plate supply standby state in a state where the printing drum 2 occupies the plate supply standby position, that is, occupies the plate supply position. It is arranged, attached and fixed at the position of the plate feeding section where the trailing edge blank portion 16d can be detected when stopped. In other words, the master remaining detection sensor 30 is disposed at a position closer to the downstream side in the master winding rotation direction of the printing drum 2 than the plate supply standby position of the printing drum 2.
In FIG. 7, reference numeral 49 denotes a sensor bracket that is fixed to the main body frame 1 </ b> A for attaching the remaining master detection sensor 30 and is disposed in the plate feeding portion. 1 and 2, reference numeral 33 indicated by hatching represents an arrangement range of the master remaining detection sensor 30 as a position where the trailing edge blank portion 16 d can be detected at the plate feeding standby position of the printing drum 2. .

As shown in FIGS. 9A and 10A, when the used master 61 on the printing drum 2 is normally peeled and discharged by the discharging unit 65 during the discharging operation, that is, remains on the printing drum 2. In the case where there is no master 16B, the printing area of the printing drum 2 is formed in a black area by blacking out normally used black ink, so that the light emitted from the light emitting element 31 of the master remaining detection sensor 30 is emitted. 31a is considerably absorbed and diffusely reflected by the black surface portion of the printing drum 2 so that the amount of the reflected light 31b is relatively small, and the light receiving element 32 receives the reflected light 31b with a small amount of light. The voltage level output from is relatively low.
For example, when the reference voltage output from the light receiving element 32 of the master remaining detection sensor 30 is set to 2.0 V, the normal state where there is no residual master 16B is less than 2.0 V, and there is an abnormality with the residual master 16B. From the experimental results, it has been found that the output voltage is about 0.5 to 1.0 V in the above state when the miss time is set to 2.0 V or more.

On the contrary, as shown in FIG. 9B and FIG. 10B, the used master 61 on the printing drum 2 is not normally peeled and discharged by the plate discharging unit 65 during the plate discharging operation. As shown in FIG. 2, the light 31a emitted from the light emitting element 31 is almost on the white film surface of the trailing edge blank portion 16d of the residual master 16B. The reflected light 31b is regularly reflected and the amount of reflected light 31b is relatively large, and the light receiving element 32 receives the reflected light 31b having a large amount of light, so that the voltage level output from the master remaining detection sensor 30 is relatively high. In the same criterion setting for the reference voltage of 2.0 V as described above, it has been found from the experimental results that the output voltage is about 3.0 to 3.5 V in the above state.
As described above, since the remaining master detection sensor 30 is a reflective photosensor, the voltage output to the control device 130 increases in proportion to the amount of light reflected and returned from the surface of the object. Based on the comparison, the output voltage from the master remaining detection sensor 30 is compared when the printing drum 2 moves to the plate feeding position after completion of the plate discharging operation and enters the plate feeding standby / stopped state. It becomes possible to detect the residual master 18B due to a peeling error at the time of waiting for the plate feeding.

  On the outer peripheral surface corresponding to the rear end blank portion 16d of the master 16 wound around the print drum 2, the master remaining detection sensor 30 accurately detects the presence of the master 16 on the print drum 2 in the same manner as the front end blank portion 16b. It is desirable to arrange a sheet-like black mylar (PET) or the like made of a light non-reflective material as the light absorbing member. In addition, the remaining master detection sensor 30 is desirably arranged as follows. That is, for example, as proposed by the present inventor in Japanese Patent Application Laid-Open No. 2002-137525, when the stencil printing apparatus 1 is left for a long period of time, an oil component that is a separation product of emulsion ink adheres to the rear end margin 16d of the master 16 In consideration of the formation of a mirror-finished ink film, the surface formed by connecting the light emitting element 31 and the light receiving element 32 is inclined with an acute angle with respect to the outer peripheral surface of the printing drum 2. It is desirable to arrange the remaining detection sensor 30.

In the conventional stencil printing apparatus, a reflection type for detecting a clamping error is provided at the same portion as the master remaining detection sensor 30 attached to the position of FIG. 7 where the rear end margin 16d of the master 16 on the printing drum 2 can be detected. Some already have a photosensor (for example, “Preport N500” manufactured by Ricoh Co., Ltd.).
In such a stencil printing apparatus, a master drum detection sensor 30 composed of a reflective photosensor is not newly added to the location, and the printing drum is changed in the same way as the master master detection sensor 30 by changing the control software. 2 can be configured to detect residual master 16B. In this way, a program on the control software can be used without increasing costs by using a general-purpose existing reflective photosensor having the same mounting position and a reflective photosensor but having different functions for other purposes. The residual master 16B on the printing drum 2 can be easily detected at the plate feed standby position of the printing drum 2 only by changing the above.

The operation panel 100 will be described with reference to FIG.
The operation panel 100 is provided on the upper front surface of the main body frame 1A adjacent to the document reading unit 70. As shown in FIG. 11, a plate making start key 104, a printing start key 105, a trial printing key 106, a continuous key 107, A clear / stop key 108, a numeric key 109, an enter key 110, a program key 111, a mode clear key 112, a printing speed setting key 113, a four-direction key 114, a display device 119, a display device 120, and the like are provided.

  The plate making start key 104 is pressed when the stencil printing apparatus 1 performs the plate making operation. When the plate making start key 104 is pressed, the plate making operation and the document reading operation are performed or partially in parallel with the plate making operation. After that, the stencil printing apparatus 1 is put into a printing standby state after the plate making operation is performed. The plate making start key 104 is a series of steps from reading an image of a document (or receiving a digital image data signal transmitted from the personal computer or the like) to discharging, plate making, plate feeding, plate printing, and paper discharge processes. It has a function as plate making start setting means for starting a process (operation).

The print start key 105 is pressed when the stencil printing apparatus 1 performs a printing operation. When the stencil printing apparatus 1 enters a print standby state and various printing conditions are set, the printing start key 105 is pressed to perform a printing operation. Is done. The trial printing key 106 is pressed when the stencil printing apparatus 1 performs the trial printing, and only one sheet is printed by pressing the trial printing key 106 after various conditions are set. The continuous key 107 is pressed before pressing the plate making start key 104 when performing the plate making operation and the printing operation continuously. After pressing the continuous key 107, the printing plate start key 104 is pressed after the printing conditions are input. Then, the printing operation is performed following the plate discharging operation, the document reading operation, and the plate making operation.
The clear / stop key 108 is pressed when the operation of the stencil printing apparatus 1 is stopped or when the numerical value is cleared. The numeric keypad 109 is used for numerical input for inputting / setting the number of printed sheets. The enter key 110 is pressed when setting a numerical value or the like during various settings, and the program key 111 is pressed when registering or calling a frequently performed operation, and the mode clear key 112 clears various modes. Pressed when returning to the initial state. The print speed setting key 113 is pressed when setting the print speed prior to the printing operation, and when it is desired to obtain a darker image or when the ambient temperature is low, the print speed is slowed down. If the ambient temperature is high, set the printing speed fast. The four-way key 114 has an up key 114a, a down key 114b, a left key 114c, and a right key 114d, and is pressed when adjusting the image position when editing an image or when selecting a value or item when making various settings. Is done.

The display device 119 is composed of a 7-segment LED (light emitting diode) and is driven via a light emitting diode driving circuit (not shown). The display device 119 mainly has a function of displaying numbers such as the number of printed sheets.
The display device 120 is composed of an LCD (liquid crystal display device) and is driven via a liquid crystal drive circuit (not shown). The display device 120 displays a message such as a status of an operation to be performed by a user, a message such as a warning, a selected function, or the like, and appropriately displays a jam location of the master 16 or the paper S, or detection of double winding of the master. Thus, it has functions as first and second notification means for reporting information.

The display device 120 has a hierarchical display structure. By pressing the selection setting keys 120a, 120b, 120c, and 120d provided below the display device 120, changes to various modes such as scaling and position adjustment, and various modes are possible. The mode can be set. Further, the display device 120 displays the state of the stencil printing apparatus 1 such as “can be made / printed” as shown in the drawing, and the liquid crystal display unit (95) described in JP-A-2003-118221. Similarly, a guidance portion 120A for appropriately displaying a warning such as a jam location on the master 16, a jam location on the paper S, a discharge jam, or a double winding detection of the master, and an operation displayed by the guidance portion 120A. In order to display the contents sequentially and to detect the jam location of the master 16, the jam location of the paper S, the discharge jam, or the double winding of the master in the stencil printing apparatus 1, and to display the failure location and the failure content specifically with pictures. Auxiliary display section 120B.
Note that the notification means is not limited to the display device 120, and may be, for example, a buzzer, a voice, or the like, or may be a proper combination of blinking / lighting display with a light emitting diode or the like.

  A control configuration of the stencil printing apparatus 1 will be described with reference to FIG. In the figure, a control device 130 includes a CPU (central processing unit) 131, an I / O (input / output) port, an I / F (interface) 134, a ROM (read-only storage device) 132, and a RAM (read-write storage). Device) 133 and the like, and a microcomputer having a configuration connected by a signal bus (not shown).

  The CPU 131 is provided in various signals from the various keys of the operation panel 100 and the main body frame 1A via a sensor input circuit (not shown) and the like, an I (input) port, and an I / F (interface) 134. Various sensors, that is, the remaining master detection sensor 30, the master missing sensor 35, the drum master presence / absence sensor 39, the plate release sensor 68, the encoder sensor 46, the home position sensor 42, various detection / detection signals from the plate feed position sensor 43, and the ROM 132. Based on the called operation program, a document reading unit driving circuit 121 for driving the document reading unit 70 and a plate making unit driving circuit for driving the plate making unit 15 through an O (output) port and an I / F (interface) 134. 122, the plate removal unit drive circuit 123 for driving the plate removal unit 60, and the printing unit 14 Printing unit drive circuit 124 that, the sheet feeding section drive circuit 125 for driving the paper feed unit 50, and outputs a drive command signal to each of the paper discharge unit drive circuit 126 for driving the sheet discharge unit 90. These drive circuits include the above-described liquid crystal drive circuit, light emitting diode drive circuit, various motor drive circuits, solenoid drive circuits, and the like of the control target components (control target drive means and the like).

  The ROM 132 stores in advance an operation program and related data of the entire stencil printing apparatus 1 shown in FIG. 13, and this operation program is appropriately called by the CPU 131. The RAM 132 has a function of temporarily storing the calculation result of the CPU 131, a function of storing data signals and ON / OFF signals set and input from various keys on the operation panel 100 and the various sensors as needed. .

The CPU 131 (hereinafter sometimes referred to as “control device 130”) has the following characteristic control functions in the present embodiment.
Based on the ON output signal from the master omission detection sensor 35, the control device 130 (CPU 131) controls the plate feeding drive circuit (the plate making unit driving circuit 122 and the printing unit) (not shown) of the plate feeding unit to end the plate feeding operation. The printing circuit driving circuit 124, the paper feeding unit driving circuit 125, and the paper discharging unit driving circuit 126 are controlled so as to prohibit the printing operation, and the plate is discharged. As a first control means for controlling the liquid crystal drive circuit of the guidance unit 120A and the auxiliary display unit 120B of the display device 120 so as to display / notify that the used master has been removed from the unit 65 (occurrence of misprinting peeling). It has the function of.
Based on the ON output signal from the master remaining detection sensor 30, the control device 130 (CPU 131) prohibits the printing operation after controlling the plate feeding drive circuit of the plate feeding means to end the plate feeding operation. In this way, the printing unit driving circuit 124, the paper feeding unit driving circuit 125, and the paper discharge unit driving circuit 126 are controlled, and the residual master 16B is present on the printing drum 2 (master double winding state due to occurrence of a discharge plate peeling error). Has a function as a second control means for controlling the liquid crystal driving circuit of the guidance unit 120A and the auxiliary display unit 120B of the display device 120 so as to display and notify the display device 120.
Further, the control device 130 (CPU 131), based on the OFF output signal from the plate removal sensor 68, displays the guidance plate 120A of the display device 120 and the auxiliary display unit so as to display / notify that there is a plate removal peeling error including a plate removal jam. It has a function as a control means for controlling the 120B liquid crystal driving circuit.

Next, the operation of the stencil printing apparatus 1 will be described with reference to the flowchart of FIG. The operation of each control target component such as the document reading unit driving circuit 121, the plate making unit driving circuit 122, the plate discharging unit driving circuit 123, the printing unit driving circuit 124, the paper feeding unit driving circuit 125, and the paper discharging unit driving circuit 126 will be described. At this time, the time when the components to be controlled are activated (driven) may be referred to as “on”, and the time when the operation (driving) is stopped is sometimes referred to as “off”. In addition, after the ON / OFF operation by each control target component is described once, the description of the operation related to ON / OFF by the same control target component is omitted. The following operations are mainly performed under the control of the control device 130 (CPU 131, hereinafter omitted).
The following operation example is based on the timing chart shown in FIG. 5 of Japanese Patent Application Laid-Open No. 2001-150786, for example, and reflects the operation according to the specific configuration of the present embodiment. Therefore, the parallel operation described in the above publication will be described in a simplified manner. This operation example represents an operation when the master size is not changed (for example, the A3 size and the printing drum 2 also has the A3 size specification).

First, referring to FIG. 13, the operation from step S1 to step S8 in which new plate making is started and normal plate discharging operation, normal plate feeding operation, and printing operation are performed will be described.
The initial state of the stencil printing apparatus 1 will be described with reference to FIG. 1. In the plate making unit 15, the plate feeding initial position where the leading end of the master 16 fed out from the master roll 16 A is held by the nip portion of the reversing roller pair 28. The printing drum 2 and the impression cylinder 9 occupy home positions, that is, the printing drum 2 is in a rotational position where the clamper 4 is located almost directly below, and the impression cylinder 9 is rotated so that the recess 11 is located almost directly above. Set to position. In this initial state, first, when the user turns on a power switch that supplies power to the respective units and devices of the stencil printing apparatus 1, the various sensors and the control device 130 are in an operable state.
Before and after this, the user places and sets a plurality of documents 73 on the document placing table 72 of the document reading unit 70, and also when the sheets S are insufficient or not on the sheet feeding tray 51. Refill and set S as appropriate.

  Next, an operation for starting new plate making is performed. First, when the user presses the plate making start key 104 to turn it on, a plate making start signal is transmitted to the control device 130. A plate making start signal when the plate making start key 104 is pressed serves as a trigger for the subsequent operation flow. As a result, a series of operations are performed ranging from plate discharge, document image reading, plate making, plate feeding, plate printing, and paper discharge. The manual operation by the user is until the prepress start key 104 is pressed, and the subsequent operations are automatically performed. Here, ink is supplied by the ink supply device 5 in the printing drum 2 to form an appropriate ink reservoir 8, and the tray lifting / lowering motor of the paper supply unit 50 is turned on to give a predetermined paper supply / separation pressure. Etc. are set.

  Next, the process proceeds to step S2, and in the state where the printing drum 2 occupies the home position and stops, the used master 16 of the previous plate is placed on the printing drum 2 based on the output signal from the drum master presence / absence sensor 39. It is determined whether or not there is. When the drum master presence / absence sensor 39 is turned on and the used master 16 of the previous plate is wound on the printing drum 2, the process proceeds to step S3, and the plate discharging operation is started. That is, the used master 16 is wound on the printing drum 2 and the printing drum 2 occupying the home position rotates in the clockwise direction indicated by the arrow in FIG. 1 when the main motor 40 is turned on. The rotation is driven until the leading end portion of the master 16 (the portion clamped by the clamper 4) reaches the plate removal position, which is the position facing the plate removal roller 61. When the main motor 40 is turned off corresponding to the plate removal position, it stops at the plate release position. Hereinafter, the on / off operation of the main motor 40 is omitted. During the plate removal and plate feeding operations, the printing drum 2 rotates and moves away from the outer peripheral surface of the impression cylinder 9.

When the printing drum 2 occupies the plate removal standby position, the clamper 4 is opened by the operation of the opening / closing device. Thereafter, the peeling roller driving motor 47 and the discharge plate swinging means are operated, so that the discharge plate peeling roller 61 occupies the peeling position while rotating as indicated by a two-dot chain line arrow direction in FIGS. Of the printing drum 2 is scooped up from the outer peripheral surface of the printing drum 2 by the discharge plate peeling roller 61.
Almost simultaneously with the operation of the peeling roller drive motor 47, the plate discharge conveying motor 48 is operated, so that the plate discharge roller pair 62 is rotationally driven in the direction indicated by the solid line arrows in FIGS. The leading end of the master 16 scooped up from the outer peripheral surface of the printing drum 2 is sent to the plate discharge roller pair 62 by the rotation of the plate release roller 61, and is discharged by the winding / rotation conveyance held between the plate discharge roller pair 62. It is conveyed into the box 67. At this time, when the discharge sensor 68 is turned on to detect the tip of the used master 16 by the discharge sensor 68, the operation of the peeling roller drive motor 47 is stopped and the discharge plate swinging means is operated. Then, the plate release roller 61 stops and occupies the separation position (see step S4).
Next, the process proceeds to step S5, and it is determined whether or not the master omission detection sensor 35 is on. The state where the master removal detection sensor 35 is turned off, that is, as shown in FIGS. 4A, 5C, 5D, etc. When the master 16 is wound up and conveyed in the plate discharging direction Xa, the plate feeding operation shown in step S6 is started. Further, in step S2, when the drum master presence sensor 39 is turned off and the used master 16 of the previous plate is not wound on the printing drum 2, the process proceeds to step S6 and the plate feeding operation is started. Is done.
As described above, when the plate ejection sensor 68 is turned on and the master missing detection sensor 35 is turned off, the printing drum 2 starts to rotate in the clockwise direction indicated by the arrow in FIGS. 1 and 2 at a low speed. At this time, the rotation speed of the discharge plate transport motor 48 is controlled so that the rotation peripheral speed of the discharge roller pair 62 exceeds the rotation peripheral speed of the printing drum 2. The used master 16 wound on the printing drum 2 is peeled off from the outer peripheral surface of the printing drum 2 while being tensioned between the printing drum 2 and the discharge roller pair 62 by the rotation of the printing drum 2. Then, it is conveyed in the direction of the arrow in FIGS.

  When it is determined that the printing drum 2 occupies a predetermined position and all the masters 16 are peeled off from the printing drum 2 and stored in the discharging plate box 67, the rotation of the discharging roller pair 62 and the printing drum 2 is stopped. In parallel with this, the compression plate 66 rotates by a predetermined angle to push the master 16 into the discharge box 67 for compression, and the printing drum 2 is driven to rotate again. When the plate-feed standby position shown in FIG. 2 is reached and the clamper 4 is opened as shown by the two-dot chain line by the operation of the opening / closing device, the plate-discharging operation is completed.

  In parallel with the movement of the printing drum 2 to the plate discharging position and the plate discharging operation described above, the image reading operation and the plate making (writing) operation of the document 73 are started in the document reading unit 70 and the plate making unit 15. Of the plurality of documents 73 set on the document table 72, the lowest document 73 is automatically conveyed to a predetermined position on the contact glass 78, and the image of the document 73 is read by the document scanning optical system. An analog image signal photoelectrically converted by the CIS 77 is input to the A / D converter. The analog image signal input to the A / D conversion unit is converted into a digital image signal, and the digital image signal is sent to the plate making control unit via the image processing unit and is made by the thermal head 22. Used for operation. The document 73 from which the image has been read is discharged onto a document discharge stand 79.

In parallel with the image reading operation of the document 73, the plate making control unit receives the digital image signal from the image processing unit and controls the thermal head 22, while the plate making operation and the plate discharging operation are automatically performed in parallel. proceed.
That is, the heating element of the thermal head 22 is selectively heated according to the digital image signal, and the film portion of the master 16 that is pressed against the platen roller 23 by the thermal head 22 is selectively heated and melted. While the punching is being performed, the plotter motor 24 is turned on, and the platen roller 23 and the tension roller pair 25 are respectively rotated, so that the master 16 that has been punched and made is transported downstream of the master transport path. On the other hand, the stepping motor 29 remains off, and the reversing roller pair 28 remains stopped. Then, by the action of the suction fan provided in the bending box (not shown), the master 16 which has been subjected to plate making from the opening of the bending box as shown in FIG. It is conveyed and stored in the bending box while it is formed so as to sag and gradually increase in bending.

  Although the description will be mixed, during the plate making operation, the printing drum 2 rotates clockwise and stops at the plate feeding position. During this time, in the plate discharging unit 60, the plate discharging operation by the operation of the plate discharging peeling roller 61, the plate discharging roller pair 62, etc. is continued, and the used master 16 corresponding to the amount of rotation of the printing drum 2 is peeled off. Discarded and discharged. During this time, the plotter motor 24 is turned on in the plate making section 15, and the plate making operation is continued while the master storing means 27 forms a bend in the master 16 that has been made.

  On the other hand, during the plate making (writing) operation and the printing drum 2 is rotationally moved to the plate feed position, in the paper feed unit 50, the paper feed motor 57 is turned on and the paper feed roller 52 and the separation roller 53 are rotated. As a result, the uppermost sheet S of the sheet feed tray 51 is fed by the cooperative action of the separation roller 53 and the separation member 54, and the leading edge of the sheet S is immediately before the nip portion of the registration roller pair 55. It is butted against the part of. Thereafter, the paper feed motor 57 is turned off and the rotation of the paper feed roller 52 and the separation roller 53 is stopped, whereby the leading edge of the paper S is brought into contact with and held by the nip portion of the registration roller pair 55 and the paper S The rear end is in contact with and held by the paper feed roller 52 and the separation roller 63.

As soon as the printing drum 2 stops at the plate feeding position, the clamper 4 is expanded for preparation of the plate feeding operation, that is, for plate-making, and the printing drum 2 enters a plate feeding standby state. During this plate feeding standby state, the plate discharging operation by the operation of the plate discharging peeling roller 61 and the plate discharging roller pair 62 in the plate discharging unit 60 is temporarily suspended.
At this time, in step S7, it is determined whether or not the master remaining detection sensor 30 is ON. When the master remaining detection sensor 30 is not on and is off, as described with reference to FIG. 9A, the state where there is no residual master 16B on the printing drum 2, that is, the plate discharge unit 65 normally It is determined that the used master 16 has been peeled and discharged, and a printing operation in step S8 described later is started.

When the plate feeding operation is started, first, the stepping motor 29 is turned on / started at a predetermined timing and the reversing roller pair 28 is rotated. It is conveyed to the clamper 4 that is expanded while being guided by the plate. When it is determined that the leading end of the master 16 that has been subjected to plate making has reached the clamper 4 by turning on the predetermined number of steps of the stepping motor 29, the stepping motor 29 is turned off and the operation of the reverse roller pair 28 is stopped simultaneously. The clamper 4 is closed. As a result, the front end of the master 16 that has been subjected to plate making is locked by the clamper 4.
At the time of printing, pulses supplied to the stepping motor 29 and the plotter motor 24 in accordance with a command from the control device 130 so that the master transport speed v2 by the stepping motor 29 becomes equal to or higher than the master transport speed v1 by the plotter motor 24. By changing the frequency (pps), the stepping motor 29 and the plotter motor 24 are controlled so that the master transport speed v2 ≧ the master transport speed v1.

Next, a master winding operation is performed. Simultaneously with the rotational movement of the printing drum 2 in the clockwise direction, the stepping motor 29 is energized to stop the rotation of the upper roller of the pair of reversing rollers 28, and the pre-made master 16 wound around the outer peripheral surface of the printing drum 2 A load is applied to prevent winding wrinkles.
After the stepping motor 29 is energized, the upper roller of the reverse roller pair 28 receives a hold load due to the excitation of the stepping motor 29 to be stopped (locked), and the lower roller of the reverse roller pair 28 is the printing drum 2. The master 2 that has been subjected to plate making by the rotation of the plate rotates and is driven and rotated by receiving the conveying force. Due to the rotational force of the printing drum 2, the master-making master 16 stored in the bending box 32 is pulled out and wound around the outer peripheral surface of the printing drum 2 without generating wrinkles or the like.
On the other hand, the reading operation in the original reading unit 70 and the writing operation in the plate making unit 15 are advanced, and the reading operation is finished. In step S6, the master plate 16 for one plate is made by the number of steps of the plotter motor 24. If it is determined by the control device 130 that the operation has been performed, the plotter motor 24 and the suction fan are turned off in response to a command from the control device 130. As a result, the rotation of the master set roller 19, the platen roller 23, and the tension roller pair 25 is stopped, and the plate making (writing) operation is completed.

At this time, the amount of bending of the master 16 already made in the master storing means 27 is gradually reduced. When the amount of bending of the master 16 is minimized, a motor (not shown) of the cutter unit 26 is turned on. The cutter unit 26 moves along the lower frame while rotating in the master width direction Y, and cuts the rear end of the master 16 that has been made. After cutting the rear end of the master 16 that has been made, the cutter unit 26 returns to the original home position, and the motor is turned off.
Next, it is determined whether or not the conveyance of the master 16 that has been made by the reversing roller pair 28 has ended, in other words, whether or not the plate feeding operation on the plate making unit 15 side has ended. When the rear end of the cut master 16 has been detected by a master tip sensor (not shown), the controller 130 finishes transporting the master 16 on the plate making unit 15 side by the reversing roller pair 28, in other words, Then, it is determined that the plate feeding on the plate making unit 15 side is finished.

  On the other hand, in the printing unit 14, the paper feeding operation is started in synchronization with the rotational movement operation in which the printing drum 2 occupies the home position. When the registration motor 58 is turned on, the paper S is fed after a predetermined timing synchronized with the rotation of the printing drum 2 by the registration roller pair 55, and the paper holding clamper 12 is expanded in accordance with this timing. After the paper S is opened and the paper S is added, the paper holding clamper 12 is closed, and the impression cylinder 9 is rotated while the paper S is held on the outer peripheral surface of the impression cylinder 9. The sheet S is fed into the nip portion. In accordance with this timing, the outer peripheral surface of the impression cylinder 9 can be brought into contact with and separated from the outer peripheral surface of the printing drum 2. After the printing operation, the outer peripheral surface of the impression cylinder 9 is separated from the outer peripheral surface of the printing drum 2. The nip portion between the printing drum 2 and the impression cylinder 9 is pressurized by an urging force of a tension printing pressure spring (not shown) provided in the impression cylinder contacting / separating means. Is pressed by the master 16 which has been made on the outer periphery of the printing drum 2 and has been made. At the time of this pressing, the ink supplied to the inner peripheral surface of the printing drum 2 by the ink roller 6 oozes out through the perforated portion of the master plate 16 on which the plate-making image has been formed. Is transferred to the surface of the paper S to form a printed image.

  The printed sheet S on which the printed image is formed is peeled off upon the paper discharge claw when the impression cylinder 9 rotates and the paper holding clamper 12 is opened in front of the paper discharge claw (not shown). While being sucked by the air, it is discharged onto the conveyor belt 95 positioned below. The printed paper S on the transport belt 95 is transported by the rotation of the suction discharge outlet roller 94 while being sucked onto the transport belt 95 by the suction fan 96, and is discharged onto the discharge tray 91 for so-called plate printing. finish. Thereafter, the printing drum 2 rotates to the home position and stops at the home position. The printed matter discharged by the plate printing is not counted as a regular printed matter.

  After the plate printing is completed, the user appropriately checks the discharged printed matter (paper S) to determine whether or not the normal printing operation may be performed, and appropriately confirms the image quality and the image position. At this time, for example, test printing including operation of the test printing key 106 is performed. If these are OK, an appropriate printing speed is set by the printing speed setting key 113, and the user presses the printing start key 105. In order to feed and print the first sheet S during normal printing, the same feeding operation, printing operation, and paper ejection operation as described above are performed. The printing operation during normal printing is different from printing in plate printing only in that printing is performed at a set printing speed faster than plate printing and counting as a regular printed matter.

  On the other hand, when the rotation operation of the registration roller pair 55 is stopped and the printing operation is finished, the platen roller 23 and the tension roller pair 25 are rotated and the stepping motor 29 is rotated in the plate making unit 15 by turning on the plotter motor 24. When the reversing roller pair 28 is turned on and the leading end portion of the master 16 of the next plate cut by the cutter unit 26 is guided by the guide conveying plate 31 and the plate feeding guide plate 42, the downstream side of the master conveying path. It is conveyed to. When the plotter motor 24 and the stepping motor 29 are actuated for a predetermined number of steps, it is determined that the leading edge of the master 16 of the next plate has occupied the plate making standby position corresponding to the plate making start position. When both of the stepping motors 29 are turned off, the rotation of the platen roller 23, the tension roller pair 25, and the reverse roller pair 28 is stopped, and a standby state is entered. Further, the thermal head 22 is separated from the platen roller 23. The document reading unit 70 is also turned off after the scanner motor or the like is turned on to move to the home position.

Next, referring to FIG. 13, the operations of Step S9 to Step S11 related to the plate feeding operation and the printing operation when a new plate making is started and an abnormal plate removal operation is performed due to the occurrence of a plate removal peeling error will be described.
In step S4, for example, as shown in FIG. 20 (a), if the discharge plate sensor 68 is not turned on once and is turned off within a predetermined time from the start of plate discharge, the control device 130 causes a plate discharge peeling error ( The guidance unit 120A and the auxiliary display unit of the display device 120 indicate that a stencil peeling error has occurred after the operation of the respective units / devices of the stencil printing apparatus 1 is stopped according to a command from the control device 130. A warning is displayed at 120B (see step S9).
As an example of this warning display, the guidance display 120A displays a message “The machine has stopped because a plate removal error has occurred. Please handle the plate removal jam.” Or “jamming location” is displayed. The user visually recognizes the displayed content, opens the front door (not shown) provided on the front surface of the stencil printing apparatus 1 and pulls out the drum unit 13, or opens the openable and closable discharging plate door provided in the plate discharging unit 60. Alternatively, if the entire plate discharging unit 60 constitutes a plate discharging unit, and this is configured to be openable and closable with respect to the main body frame 1A, the plate discharging unit is opened or the portion of the plate discharging unit 65 Then, the discharged paper jam processing is performed in a state where the printing drum 2 portion opposed thereto is exposed. In addition, as will be described later, the drum unit 13 shown in FIG. 2, FIG. 18, FIG.

In step S5, when the output signal from the master dropout detection sensor 35 is on, as shown in FIGS. 4B, 5A, and 5B, peeling and winding is performed by the plate removal unit 65. The control device 130 determines that the used master 16 that has been started has left the plate discharge unit 65 and has returned to the plate discharge return direction Xb, and in response to a command from the control device 130, a plate supply drive circuit (not shown) of the plate supply means. After the plate feeding operation is completed (included in the plate making unit driving circuit 122 and the printing unit driving circuit 124), the printing unit driving circuit 124, the paper feeding unit driving circuit 125, and the paper discharge unit driving circuit 126 perform the printing operation. Without performing (printing operation prohibition), the operation of each unit / device is stopped.
At this time, the printing drum 2 is stopped at the attach / detach position where it can be detached from the main body frame 1A in the vicinity of the home position. At this attachment / detachment position, the user can easily attach / detach the drum unit 13 to / from the main body frame 1A. Thereafter, a warning is displayed on the guidance unit 120A and the auxiliary display unit 120B of the display device 120 that the used master 16 has been removed from the plate release unit 65 (occurrence of a plate release peeling error) (see step S10).

  As an example of this warning display, the guidance unit 120A displays the message “Master double winding due to misprinting has occurred, so the machine has stopped. Please perform jam removal or master double winding.” However, “master double winding occurrence location due to missed plate peeling” is displayed on the auxiliary display portion 120B. The user visually recognizes the display contents, opens the front door (not shown) provided on the front surface of the stencil printing apparatus 1 in the same manner as described above, pulls out the drum unit 13, and completely removes the drum unit 13. The master double winding removal process is performed with the master double winding outer peripheral portion exposed.

If the output signal from the master remaining detection sensor 30 is OFF in step S7, it is determined that the normal plate removal operation in which the output signal is OFF in step S5 due to, for example, failure or erroneous detection of the master missing detection sensor 35. Is assumed. Even in such a case where a missed plate peeling error is overlooked, if the output signal from the master remaining detection sensor 30 is OFF in step S7, as shown in FIGS. 9B and 10B. In addition, when the printing drum 2 is in the plate feeding standby position, the control device 130 determines that there is a residual master 16B on the printing drum 2 due to an error in removing the plate removal, and the plate feeding means is illustrated by a command from the control device 130. After the plate feeding driving circuit (included in the plate making unit driving circuit 122 and the printing unit driving circuit 124) finishes the plate feeding operation, the printing unit driving circuit 124, the paper feeding unit driving circuit 125, and the paper discharging unit driving circuit 126 does not perform the printing operation (printing operation is prohibited), and the operation of each unit / device is stopped.
At this time, the printing drum 2 is stopped at the attach / detach position where it can be detached from the main body frame 1A in the vicinity of the home position. Thereafter, a warning is displayed on the guidance unit 120A and the auxiliary display unit 120B of the display device 120 that the used master 16 has been removed from the plate discharge unit 65 (occurrence of a plate release peeling error) (see step S11). The warning display example and processing contents in this case are basically the same as in step S10.

In this embodiment, the advantage of using the two sensors, the master remaining detection sensor 30 and the master missing detection sensor 35, is that, for example, as described above, the drum master presence / absence sensor 39 is mastered on the printing drum due to failure or erroneous detection. In the case where it is detected that there is no master in spite of being wound, since the control is made to skip the plate removal operation and shift to the plate feeding operation, the remaining master on the printing drum is surely detected by the master remaining detection sensor 30. This is because it can be detected. That is, in the above state, the master missing detection sensor 35 with the filler 34 cannot detect because there is no plate discharging operation, so that the trailing edge margin detection of the master on the printing drum in the plate feeding standby position of the printing drum is detected. This is because detection can be performed only by the master remaining detection sensor 30.
Here, the erroneous detection of the drum master presence / absence sensor 39 is because the oil component of the ink is separated into the master wound around the printing drum due to ink bleeding or the like caused by leaving the machine for a long time, and the oil soaks into the master. The master sees through and black, such as ink on the printing drum, is detected by the drum master presence / absence sensor 39, which is a reflection type photosensor, so that it is detected that there is no master even though the master is wound. Refers to the phenomenon.

As described above, according to the present embodiment, it is a matter of course that the effects described in the effect column of the above-described invention can be obtained, and the advantages and effects described and described later as appropriate in the present embodiment.
According to the present embodiment, the master missing detection sensor 35 is a transmissive photosensor provided with a filler 34, and therefore, the used master 16 is removed from the plate discharge unit 65 (returning to the printing drum 2 side) as a filler. 34 is configured to be movable in the discharge plate return direction Xb (extraction direction), so that highly reliable detection can be performed, and the cost can be increased by using a general-purpose sensor equipped with a filler 34. Can be kept to a minimum.
Further, according to the present embodiment, since the master remaining detection sensor 30 is a reflection type photosensor, the cost increase can be minimized by using a general-purpose sensor.

  FIG. 14 shows a modification of the embodiment shown in FIGS. In the modification shown in FIG. 14, the size of the printing drum (plate cylinder) is an A3 size capable of winding a master having an A3 size, as compared with the stencil printing apparatus 1 of the embodiment shown in FIGS. In addition, in order to reduce the consumption of the master, when the paper size is A4 or less and a plurality of originals are read (when the originals are continuously read via the ADF or the PC controller), the master wound around the printing drum. The only difference is that it is a stencil printing machine equipped with a known A4 cut mechanism for cutting the length short.

  In the stencil printing apparatus equipped with the A4 cut mechanism, when the function of the A4 cut mechanism is used, the trailing edge blank portion 16d of the master 16 wound around the printing drum 2 is supplied to the plate as shown in FIG. In the standby position state, this is a portion that cannot be detected by the drum master presence / absence sensor 39, which is a reflection type photosensor attached at the same position of the main body frame shown in FIGS. That is, since the master 16 is cut short, it can be detected only by the master remaining detection sensor 30.

  Thus, in this embodiment and this modification, by disposing the master missing detection sensor 35 in the plate removal unit and the master remaining detection sensor 30 in the plate feeding unit, respectively, when a conventional sensor malfunction occurs or a new function is provided. Even when added, it is possible to reliably detect the double winding of the master.

There are two types of plate discharging means. That is, as a pair of displaceable peeling rollers (hereinafter referred to as “peeling roller displacement type”) that approaches or contacts a used master on a printing drum (plate cylinder) and peels and discharges the master, or as a master tip holding means A pair of discharge rollers that have an elastic thin plate (called a kicking-out means or a kicking-out member) provided in the clamper arrangement portion of the used master and can hold the tip of the used master that has been kicked out by the thin elastic plate to release and release the plate. (Hereinafter referred to as “displacement roller fixed type”). As an example of a peeling roller displacement type, the example shown in the said embodiment, a modification, etc. is mentioned.
As an example of the plate discharge roller fixed type, for example, as disclosed in Japanese Patent Application Laid-Open No. 2000-43394, a blade roller having a plurality of elastic blades radially extending in the centrifugal direction beside one roller of the plate discharge roller pair. The elastic blade is brought into contact with the outer peripheral surface of the other roller while being elastically bent and deformed, and the master peeled off by the elastic blade is pulled in, and the master that has been peeled off by the restoring repulsive force due to the elastic deformation of the elastic blade is provided. There is one that is struck so as not to be wound around the outer peripheral surface of the one of the rollers.
The present invention is not limited to the release roller displacement type plate discharge unit 65 shown in the above-described embodiment, modification, etc., for example, a plate discharge roller pair (65) shown in FIG. 1 of Japanese Patent No. 3332267, Needless to say, the present invention can also be applied to the type of fixed plate discharge roller.

In the present invention, as shown in the above-described embodiment and the like, the stencil printing apparatus 1 is provided with a printing unit that performs a printing operation by directly pressing the paper S against the master 16 on the printing drum 2 (plate cylinder). For example, a printing cylinder (including cardboard, thin paper, postcards, envelopes, etc.) is indirectly supplied to the master on the plate cylinder by interposing a transfer cylinder between the plate cylinder and the pressing means. It may be a stencil printing apparatus provided with a printing unit that performs a printing operation including pressing on both sides by pressing.
As described above, the present invention has been described with respect to specific embodiments and modifications including examples. However, the present invention is not limited to the above-described embodiments and modifications, and these may be combined as appropriate. It will be apparent to those skilled in the art that various embodiments and examples can be configured within the scope of the present invention in accordance with the necessity and application thereof.

1 is a schematic front view of an entire stencil printing apparatus showing an embodiment of the present invention. It is the partial cross section front view which expanded the principal part of FIG. (A) is a master missing detection sensor arranged in the discharged plate portion of FIG. 1, and (b) is a main portion showing the mounting positions of the master missing detection sensor and the discharged plate sensor arranged in the discharged plate portion. FIG. (A) shows the off detection operation of the master removal detection sensor with filler when the used master is normally wound up in the direction of discharging by the discharging unit of FIG. 1, and (b) is used from the discharging unit. FIG. 6 is a simplified front view showing an on-detection operation of a master removal detection sensor with a filler when a master that has already been removed and a master that has missed removal is returned in the return direction. (A) is a simplified front view for explaining an on-detection operation when a filler of a master removal detection sensor with a filler falls when a master that has failed to release the plate is returned to the plate release return direction; A simplified side view showing the operation, (c) is a simplified front view for explaining the off-detection operation when the filler of the master missing detection sensor with filler does not fall down, and (d) is a simplified diagram showing the operation. FIG. (A) is a simplified front view showing the positional relationship between the rear end margin of the master on the printing drum and the master remaining detection sensor in the plate feeding standby state in which the printing drum is stopped at the plate feeding position; These are top views for developing and explaining a master on the printing drum. It is a perspective view of the principal part of the plate feeding part which shows the attachment position of the master remaining detection sensor. It is a perspective view of the principal part for supplementary explanation of Drawing 6 (b). (A) is a master remaining detection sensor OFF detection operation when there is no residual master or the like on the printing drum due to a normal plate removal operation, and (b) is a case where there is a residual master on the printing drum due to a plate removal error. It is a simplified front view of the principal part for demonstrating each ON detection operation | movement of a master remaining detection sensor. (A) is a master remaining detection sensor OFF detection operation when there is no residual master or the like on the printing drum due to a normal plate removal operation, and (b) is a case where there is a residual master on the printing drum due to a plate removal error. It is a simplified front view for demonstrating each ON detection operation | movement of a master remaining detection sensor. FIG. 2 is a plan view of an operation panel of the stencil printing apparatus in FIG. 1. It is a block diagram which shows the control structure of the whole stencil printing apparatus in FIG. 2 is a flowchart showing an operation sequence of a main part of the stencil printing apparatus in FIG. 1. (A), (b) is a simplified front view for demonstrating operation | movement of the master remaining detection sensor in the modification of the said embodiment. In the conventional stencil printing apparatus, it is a simplified front view for explaining the winding of the used master by the evacuation unit in the evacuation standby position of the printing drum and the operation of the evacuation sensor. In the conventional stencil printing apparatus, the principal part of FIG. 15 is expanded and the simplified front view for demonstrating the same content in detail. It is a perspective view of the principal part which shows the attachment position of the plate removal sensor arrange | positioned at the plate removal part of FIG. In the conventional stencil printing apparatus, it is the perspective view of the principal part for demonstrating the peeling and winding operation | movement of the used master by the stencil discharge unit in the stencil discharge standby position state of a printing drum. In the conventional stencil printing machine, after the used master has been peeled off and discharged from the printing drum normally, the operation of feeding the new master from the plate making unit in the plate waiting state of the printing drum is explained. It is a simplified front view for doing. It is a timing chart for demonstrating the detection of the detachment plate peeling mistake of the drum master presence sensor and the evacuation sensor in the conventional stencil printing apparatus. In a conventional stencil printing apparatus, after a used master on a printing drum is once peeled off by a plate discharging unit and wound up to a plate discharging sensor, the master is removed from the plate discharging unit and returned to the printing drum side. It is a simplified front view for demonstrating ON detection operation | movement. In the conventional stencil printing apparatus, it is a simplified front view for explaining the operation in which a new master-making master is fed from the plate-making unit in a plate-feed standby state of a printing drum. In a conventional stencil printing device, after a master master detachment peeling error from the printing drum occurs, the remaining master remains on the printing drum. It is a simplified front view for demonstrating the operation | movement by which the new master made master plate is supplied. In a conventional stencil printing apparatus, a simplified front view for explaining a master double winding state in which a new master-made master is wound on a state where a residual master remains on a printing drum. is there. It is a perspective view of the principal part for demonstrating the same content as FIG.

Explanation of symbols

1 stencil printing machine 2 printing drum (plate cylinder)
5 Ink supply device 9 Impression cylinder (pressing means)
14 Printing section 15 Plate making section 16 Master 22 Thermal head (plate making means)
23 Platen roller (master conveying means)
24 Plotter motor 27 Master storage means 28 Reverse roller pair (plate feeding means)
29 Stepping motor (plate feeding drive means)
30 Master remaining detection sensor (master remaining presence detection means)
34 Filler (shading piece)
35 Master missing detection sensor (master missing detection means)
39 Drum master presence / absence sensor (master presence / absence detection means)
40 Main motor 47 Peeling roller drive motor (plate removal drive means)
48 Discharge plate transport motor (Discard drive means)
50 Paper Feeding Unit 60 Plate Removal Unit 61 Plate Removal Peeling Roller (Plate Removal Unit)
62 Displacement roller pair (Discarding means)
63 On the plate removal roller (plate removal means)
64 Under the plate removal roller (plate removal means)
65 Plate removal unit (plate removal means)
68 Discharge sensor (Discharge detection means)
70 Document Reading Unit 90 Paper Discharge Unit 100 Operation Panel 120 Display Device (Notification Unit)
120A guidance section (first and second notification means)
120B Auxiliary display section (first and second notification means)
130 Control device (first and second control means)
131 CPU (constitutes first and second control means)
S paper (printed media)
Xa Ejection direction Xb Ejection return direction X Paper transport direction

Claims (6)

A plate cylinder around which a pre-printed master is wound, a plate discharging means for peeling and discharging a used master on the plate cylinder, and a plate supplying means for performing a plate supplying operation for supplying the pre-made master to the plate cylinder And a stencil printing apparatus comprising a printing unit that performs a printing operation by directly or indirectly pressing a printing medium on a master plate on the plate cylinder,
A stencil printing apparatus comprising: a master removal detecting means for detecting the removal of a used master from the plate removal means when the used master is peeled off and discharged by the plate removal means. In the stencil printing apparatus according to claim 1,
The stencil printing apparatus, wherein the master missing detection means is disposed on a used master discharging path between the plate cylinder and the plate discharging means. In the stencil printing apparatus according to claim 1 or 2,
First notifying means for notifying information;
Based on the output signal from the master missing detection means, after the plate feeding means to end the plate feeding operation, the printing means is prohibited to prohibit the printing operation, and a first notification means is provided. And first control means for informing that the used master has been removed from the plate discharging means,
A stencil printing apparatus comprising: In the stencil printing apparatus according to any one of claims 1 to 3,
A stencil printing apparatus comprising master remaining presence / absence detecting means for detecting presence / absence of a used master remaining on the plate cylinder without being peeled or discharged by the plate discharging means. In the stencil printing apparatus according to claim 4,
The master remaining presence / absence detecting means is arranged at a position where the trailing edge margin of the used master remaining on the plate cylinder in a state where the plate cylinder occupies a predetermined plate feeding position can be detected. A stencil printing apparatus. In the stencil printing apparatus according to any one of claims 3 to 6,
Second informing means for informing information;
Based on an output signal from the master remaining presence / absence detecting means, the plate supplying means is used to end the plate supplying operation, and then the printing means is used to prohibit the printing operation, and second informing means. Second control means for informing that there is a used master remaining on the plate cylinder;
A stencil printing apparatus comprising:

Images