JP4608055B2 - Printing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printing apparatus having a function of cutting a master into a predetermined length.
[0002]
[Prior art]
As a stencil printing device that is a form of a printing device that prints on paper using a master wound on the outer peripheral surface of a printing drum, a digital thermal stencil printing device that performs from discharging to printing and from plate making to printing is performed. A plate making apparatus is known. In such a printing apparatus, a plotter unit as a plate making / plate feeding unit is provided, and a plate is fed while making a master with this plotter unit. The supplied master is wound around the outer peripheral surface of the printing drum by rotating the printing drum with its leading end locked by a master locking means such as a clamper provided on the outer peripheral surface of the printing drum, and cut. It is cut into a predetermined length by means. The predetermined length here is usually the length of one plate. The length for one plate is a length corresponding to the length of the drum outer peripheral surface corresponding to the paper size. For example, if the printing drum is compliant with JIS standard A3 size, the length of one plate indicates the length that can be printed on A3 size paper, and the printing drum is JIS standard. When it corresponds to the B5 size, the length of one plate indicates the length that can be printed on the B5 size paper.
[0003]
In the printing apparatus, in order to reduce cutting failure when cutting the master, a conveyance roller for feeding the master is provided on the upstream side of the cutting unit, and a tension roller that applies tension to the master on the downstream side of the cutting unit. And the master is tensioned by this roller and cut. Alternatively, it has been proposed that the printing drum is rotated with the leading edge of the master fed by the conveying roller being locked by the master locking means, and the master is stretched using the rotation of the printing drum to cut the master. Yes.
[0004]
[Problems to be solved by the invention]
In a printing apparatus having a master cutting function, how to reliably cut the master into a predetermined length is an important issue. Considering the simplification of the device configuration and the reduction in the number of parts, it is possible to rotate the printing drum while the front end of the master is locked by the master locking means, and use this rotation to apply tension to the master for cutting. preferable. However, in the case of this method, if the master is not reliably cut at a predetermined length, the master may be wound around the outer peripheral surface of the printing drum multiple times. In such a state, not only good printing is not performed, but also the master is wasted by rotating the printing drum until there is no master roll stored in a roll in the plotter unit. In addition, if the master is wound many times, the master locking means may be poorly opened or closed, and the master may interfere with the printing pressure member, resulting in a mechanical lock that locks the device.
Even in a printing apparatus that cuts while applying tension with a tension roller, if the master is fed without being cut to an accurate length, there is a risk that the master may overlap with the master locking means. .
SUMMARY OF THE INVENTION An object of the present invention is to provide a printing apparatus that can reduce defects due to a master cutting failure.
[0005]
[Means for Solving the Problems]
  In order to achieve the above object, a first aspect of the present invention includes a printing drum that is rotationally driven by a driving source, master locking means that is provided on the outer peripheral surface of the printing drum and that locks the leading end of the master, and a master. In a printing apparatus having cutting means for cutting to a predetermined length,Presence / absence of the master on the printing drum and the presence / absence of detecting whether the master has been cut to a predetermined length after detecting the presence / absence of the masterThe detection means and the master is cut to a predetermined lengthMaster presenceAnd a control means for stopping the drive of the drive source when the detection means does not detect. According to the present invention, the master has been cut to a predetermined length.Master presenceIf it is not detected by the detection means, the drive of the drive source for rotating the printing drum is controlled to be stopped by the control means, so that unnecessary conveyance of the master roll and excessive winding of the master around the outer peripheral surface of the printing drum are eliminated.
[0006]
  Claim4The invention described in claim 12 or 3The printing apparatus described above is characterized in that the cutting means performs a cutting operation in a state where the leading end of the master is locked by the master locking means and tension is applied to the master by the rotation of the printing drum. According to the present invention, if the master is not a predetermined length, the drive source is stopped, so that unnecessary conveyance of the master roll and excessive winding of the master around the outer peripheral surface of the printing drum are eliminated. Further, since the master is given tension by the rotation of the printing drum, it is not necessary to newly provide a member for giving tension to the master.
[0007]
  Claim 1In the invention describedLeaveThe master presence / absence detection means includes a first detected portion disposed within the master winding range of the outer peripheral surface of the printing drum,Print drum cut to a predetermined lengthofPrinting drum where the rear end of the master is located when wound on the outer peripheral surfaceofProvided on the outer peripheral surfaceSecondDetected part and printing drumofPlaced near the outer surface,First and secondIt has the feature of having a detector for detecting the detected part.
[0008]
  Claim2The described invention is claimed.1In the printing apparatus described,SecondMaster to be detected cut to a predetermined length is the printing drumofIt is characterized by being a screen leather portion located on the downstream side in the master winding direction from the rear end of the master when wound around the outer peripheral surface. For this reason, it is not necessary to newly provide a detected part.
[0009]
  Claim3The described inventionIn a printing apparatus having a printing drum that is rotationally driven by a driving source, master locking means that is provided on the outer peripheral surface of the printing drum and that locks the leading end of the master, and cutting means that cuts the master into a predetermined length Detecting the presence or absence of a master on the printing drum, and after detecting the presence or absence of the master, a master presence / absence detecting means for detecting whether the master has been cut to a predetermined length, and the master being cut to a predetermined length Control means for stopping the drive of the drive source when the master presence / absence detection means does not detect the master presence / absence detection means, the master presence / absence detection means being arranged within the master winding range of the outer peripheral surface of the printing drum. And
Provided in the master locking meansSecondLocated near the detected part and the outer peripheral surface of the printing drumFirst and secondA detector to detect the detected part andHaveIt features to do.
[0010]
  Claim5The described invention is claimed.1, 2 or 3In the printing apparatus described,SecondIt is characterized in that the detected part is black and the detector is a reflective optical sensor. For this reason, the light emitted from the optical sensor is reflected by the master when the master is cut longer than a predetermined length, and is reflected by the black detected portion when the master is cut to a predetermined length. The
[0011]
  Claim6The invention described in claim 1 to claim 15In the printing apparatus according to any one of the above, the control unit is configured such that the master is a printing drum.ofIt is characterized in that, at the time of printing performed after being wound around the outer peripheral surface, it is determined that the master is not a predetermined length and the driving of the driving source is stopped. For this reason, if the master is not a predetermined length at the time of printing, the drive source is stopped, so that unnecessary conveyance of the master roll and excessive winding of the master around the outer peripheral surface of the printing drum are eliminated.
[0012]
  Claim7The invention described in claim 1 to claim 16In the printing apparatus according to any one of the above, the control unit includes a notification unit that reports a master length abnormality under the control of the control unit, and the control unit has the master cut into a predetermined length. When the detection means does not detect, the notification means is in the notification state. According to the present invention, an abnormality in the master length is notified by the notification means.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a schematic configuration diagram of a stencil printing apparatus which is an embodiment of a printing apparatus to which the present invention is applied. In the figure, the stencil printing apparatus includes a printing drum 1, a plotter unit 40, and a plate discharging unit 50 in the printing apparatus main body 100. A paper feed unit 60 is disposed on the right side of the printing apparatus main body 100, a paper discharge unit 70 is disposed on the left side, and a scanner 200 serving as an image reading unit is disposed on the upper side.
[0014]
The paper feed unit 60 and the paper discharge unit 70 are disposed in the printing apparatus main body 100 so that the paper 61 stacked on the paper feed tray 64 disposed in the paper feed unit 60 can be conveyed substantially horizontally toward the paper discharge unit 70. Each is arranged. The paper feed unit 60 is provided with a paper feed roller 62 and a separation plate 63 for feeding the paper 61 on the paper feed tray 64 one by one. Reference numeral 65 denotes a side fence provided on the paper feed tray 64. The paper discharge unit 70 includes a paper discharge tray 71 that receives printed paper, a side fence 72 provided on the paper discharge tray 71, and an end fence 73 that collides with the front end of the paper.
[0015]
A press roller 48 serving as a printing pressure member is disposed at a position facing the printing drum 1 on a sheet conveyance path 67 that connects the sheet feeding unit 60 and the sheet discharging unit 70. As the printing pressure member, a known pressure drum may be used instead of the press roller 48. The press roller 48 can be brought into and out of contact with the outer peripheral surface (hereinafter referred to as “drum outer peripheral surface”) 1 a of the printing drum 1 by a swing mechanism (not shown). The press roller 48 is urged toward the drum outer peripheral surface 1a by the urging means provided in the swing mechanism. In the present embodiment, a facing portion between the press roller 48 and the printing drum 1 is a printing unit 49.
[0016]
A registration roller pair 66 is disposed on a paper conveyance path 67 positioned between the press roller 48 and the paper feed roller 62. The registration roller pair 66 feeds the paper 61 sent out from the paper feed tray 64 at a timing when the front end of the plate-making image coincides with the front end of the paper at the printing unit 49.
[0017]
Between the printing unit 49 and the paper discharge unit 70, an intermediate conveyance device 80 that conveys the paper 61 that has passed through the printing unit 49 to the paper discharge unit 70 is disposed. The intermediate conveying device 80 is obtained by winding an endless perforated belt 83 around a pair of rollers 81 and 82, one of which is on the driving side and the other is on the driven side. In this embodiment, the endless perforating belt 83 rotates in the counterclockwise direction. Below the plateless perforating belt 83, a suction fan 84 for adsorbing the paper 61 onto the belt is disposed. Above the plateless perforating belt 83, a separation claw 85 for separating the paper 61 that is wound up due to the viscosity of the ink from the drum outer peripheral surface 1a side is disposed.
[0018]
The scanner 200 is a well-known scanner that reads a document surface of a leaf paper document or a page document set on a document placement table (not shown) with an exposure optical system and converts the document surface into digital image information. The plate discharging means 50 is a well-known device that is wound around the drum outer peripheral surface 1a and peels off the used master that has been used from the drum outer peripheral surface 1a.
[0019]
The porous cylindrical printing drum 1 rotatably supported on the printing apparatus main body 100 by a support shaft 43 has a clamper 5 as a master locking means for holding a plate-making master 106 to be described later on the drum outer peripheral surface 1a. The drum is driven to rotate in the direction indicated by the arrow A by a drum drive motor 41 serving as a drive source. This rotation direction is the master winding direction and also the printing direction. For this reason, the following is collectively referred to as “drum rotation direction A”.
[0020]
As shown in FIG. 1, the clamper 5 extends in the direction of one generatrix of the non-perforated portion 101 of the printing drum 1 and is supported by a rotating shaft 5a extending in the same direction. By being opened and closed as appropriate by an opening / closing device (not shown), the master tip is locked together and the master tip is unlocked.
[0021]
The printing drum 1 includes a non-perforated portion 101, a screen leather portion 102 having a range θ1, and a perforated portion 109. The screen leather portion 102 has a length in the generatrix direction of the printing drum 1 and is upstream of the non-perforated portion 101 in the drum rotation direction A, and the plate making master 106 to be wound has a predetermined length. In this case, it is disposed downstream of the rear end in the drum rotation direction A. This screen leather portion 102 is black, and when the master to be wound is of a predetermined length, the rear end is not placed and the detection means for detecting whether the master has been cut to the predetermined length. This constitutes the performance detection unit. On the downstream side of the non-perforated portion 101 in the drum rotation direction A, a label portion 103 constituting a detected portion for detecting the presence or absence of a master on the printing drum 1 is provided. This label portion is black and is disposed within the master winding range.
[0022]
In the vicinity of the drum outer peripheral surface 1a, a master presence / absence detection sensor 104 as a detector for detecting the screen leather portion 102 as the detected portion and the label portion 103 is disposed. The master presence / absence detection sensor 104 is an optical sensor having a light emitting unit and a light receiving unit. The master presence / absence detection sensor 104 outputs low light (Lo) when the irradiation light 107 emitted from the light emitting part is applied to the label part 103 or the screen leather part 102 of the drum outer peripheral surface 1a and the reflected light is received. When the reflected light is received by irradiating the prepressed master 106, the output characteristic is such that the output becomes high (Hi). The master presence / absence detection sensor 104 and the screen leather portion 102 constitute detection means for detecting whether the master is cut to a predetermined length when it is locked by the clamper 5 and wound around the drum outer peripheral surface 1a. ing. On one side surface of the printing drum 1, a detection protrusion 111 is provided so as to protrude in the bus line direction. A frame (not shown) facing the one side surface includes a home position sensor 110 that detects the home position of the printing drum 1 by detecting the detection protrusion 111 and a drum position detection sensor 112 that detects the position of the printing drum 1. It is fixed.
[0023]
As shown in FIG. 2, an ink reservoir 47 that stores ink supplied from a supply port 44 formed in the support shaft 43 is disposed inside the printing drum 1, and an ink roller 45 and a doctor roller 46 disposed so as to face the ink roller 45. And is formed by.
[0024]
As shown in FIG. 1, the plotter unit 40 includes a master storage unit 2, a plate making / plate feeding unit 3, a cutting unit 4, and the like, and is disposed on the upper right side of the printing drum 1. The master storage means 2 supports a core portion 6b of a master roll 6a in which a master 6 constituted by laminating a porous support and a thermoplastic resin film in a roll shape is rotatably and detachably supported. Yes.
[0025]
A plate making / plate feeding means 3 is disposed between the printing drum 1 and the master storage means 2. The plate-making / plate-feeding means 3 includes a thermal head 7 that performs hot-drilling plate-making on the thermoplastic resin film surface of the master 6 according to image information, and a platen roller 8 that conveys the master 6 while pressing the master 6 against the thermal head 7 relatively. It is configured. The platen roller 8 is rotationally driven by the stepping motor 30 and conveys the master 6 in the plate feeding direction indicated by the arrow B (hereinafter referred to as “plate feeding direction B”). The thermal head 7 is attached to a frame (not shown) of the printing apparatus main body, which is a fixed portion. The platen roller 8 is rotatably attached to a cover 9 that is a movable part that is supported on the printing apparatus main body so as to be opened and closed about a support shaft 9a. An escape hole (not shown) having a width larger than the width of the master 6 is formed in a portion of the cover 9 near the support shaft 9a to allow the master 106 made of the plate to be sufficiently bent.
[0026]
A guide plate 10 and a transport roller 11 for transporting the master 6 are disposed downstream of the platen roller 8 in the plate feeding direction B. The guide plate 10 is fixed to a frame (not shown) of the printing apparatus main body. The transport roller 11 is attached to the cover 9 and is driven to rotate substantially in synchronization with the platen roller 8 by drive means and drive force transmission means (not shown) attached to the printing apparatus main body. The peripheral speed of the transport roller 11 is set slightly faster than the peripheral speed of the platen roller 8. For this reason, tension is applied to the master 106 that has been made at the portion between the platen roller 8 and the conveying roller 11. In addition, it is good also as a structure which makes the drive means of the conveyance roller 11 the stepping motor 30 which is a drive means of the platen roller 8, ie, the structure which transmits the rotational force of the platen roller 8 to the conveyance roller 11 via the idle gear which is not shown in figure.
[0027]
A cutting means 4 is disposed downstream of the transport roller 11 in the plate feeding direction B. The cutting means 4 is mainly composed of a frame 12 as a cutting means body, a holder 13, a rotational movement means 14, and the like. The frame 12 formed by bending the plate material into a substantially U-shape and having a length exceeding the width of the master 6 is shown in the printing apparatus main body so that its longitudinal direction is along the master width direction perpendicular to the plate feeding direction B. Do not stick to the frame.
[0028]
The holder 13 that integrally connects the upper blade holder 13a that rotatably supports the disk-shaped upper blade 16a and the lower blade holder 13b that rotatably supports the lower blade 16b of the same shape as the upper blade 16a is a frame. 12 is supported so as to be movable in the master width direction. The holder 13 is connected to a rotational movement means 14 and is moved in the master width direction. In the cutting means 4, when the rotational movement means 14 is driven, the upper blade 16 a and the lower blade 16 b are simultaneously moved in the master width direction along with the holder 13 to cut the plate making master 106 to a predetermined length. The predetermined length is the length of one plate corresponding to the length of the outer peripheral surface of the printing drum 1.
[0029]
A guide member 21 is disposed at a position between the conveying roller 11 and the cutting unit 4. The guide plate 21 is located above the plate making master 106 during plate making standby and plate making conveyance, and has a pressing function for the plate making master 106.
[0030]
A guide member 22 and a movable guide plate 23 are disposed downstream of the cutting unit 4 in the paper feeding direction B. One end of the guide member 22 is attached to the cover 9, and the other end is bent, and guides the plate-making master 106 that has been formed and bent to guide a relief hole (not shown) formed in the cover 9.
[0031]
The movable guide plate 23 arranged to face the guide member 22 is supported by a side plate (not shown) of the printing apparatus main body so as to be swingable, and the free end thereof is in the movement path of the holder 13 of the cutting means 4. And located below the frame 12. The movable guide plate 23 is moved by a guide line swinging means (not shown) such as a solenoid fixed to a side plate (not shown) of the printing apparatus main body so that the solid line position (first position) in FIG. The position is selectively positioned at the two-dot chain line position (second position) in FIG. Thereby, the member which guides conveyance of a master continuously with the upper blade 16a and the lower blade 16b can be arrange | positioned in the downstream of the plate feeding direction B rather than the arrangement position of the upper blade 16a and the lower blade 16b. For this reason, a large gap or a step is not generated between the frame 12 and a guide plate 25 described later, and poor conveyance of the plate making master 106 in the plotter unit 40 is prevented.
[0032]
Guide plates 24 and 25 are disposed downstream of the movable guide plate 23 in the plate feeding direction B. The guide plate 24 positioned above the master conveyance path is attached to a side plate (not shown) of the printing apparatus main body, and guides the plate-making master 106 which has been plate-formed and formed to be bent to the printing drum 1. A guide plate 25 disposed opposite to the guide plate 24 via the master transport path is attached to a side plate (not shown) of the printing apparatus main body. The guide plate 25 has a notch (not shown) for allowing a circumferential surface of a brake roller 26 described later to face the master transport path.
[0033]
The brake roller 26 is disposed in the vicinity of the downstream end of the guide plate 25 in the plate feeding direction. The brake roller 26 whose outer peripheral surface is covered with a high frictional resistance member can be driven and rotated via a torque limiter (not shown), and is selected between a solid line position and a two-dot chain line position in the figure by a roller swinging means (not shown). Positioned. In this embodiment, the front end 106 a of the plate making master 106 is locked by the clamper 5, and the cutting operation by the cutting means 4 is performed in a state where tension is applied to the master 106 by the rotation of the printing drum 1.
[0034]
As shown in FIG. 2, an operation panel 201 as an operation unit is disposed on the upper part of the printing apparatus main body 100. The operation panel 201 is provided with a notification display device 202 composed of an LCD or the like as notification means for notifying the master length abnormality. Although not shown, the operation panel 201 is provided with a plate making start key for starting a plate making operation, a printing start key for starting a printing operation, a stop key for stopping the operation of the apparatus, and a numeric keypad for inputting numerical information such as the number of printed sheets. Yes.
[0035]
A control unit 90 is disposed inside the printing apparatus main body 100. The control unit 90 is a known microcomputer having a ROM, a RAM, and a CPU, and its main part is configured. As shown in FIG. 3, the master presence / absence detection sensor 104, the home position sensor 110, the drum position detection sensor 112, and keys of an operation panel (not shown) are electrically connected to the input side of the control means 90. On the output side of the control means 90, the stepping motor 30, the drum drive motor 41, and the notification display device 202 are electrically connected. The stepping motor 30, the drum drive motor 41, and the notification display device 202 are under the control of the control means 90. In the control unit 90, a program for performing a control process for stopping the driving of the drum drive motor 41 when the master presence / absence detection sensor 104 shown in FIG. 1 does not detect that the plate making master 106 is cut to a predetermined length. Is stored in a ROM (not shown).
[0036]
The operation of the stencil printing apparatus having such a configuration will be described with reference to the flowchart shown in FIG. When a plate making start key (not shown) is operated to start plate making, in step S1 of FIG. 5, the plate discharging is started and the used master wound around the drum outer peripheral surface 1a is discarded from the drum outer peripheral surface 1a by the plate discharging device 50. The In this embodiment, in parallel with the start of plate removal, reading of an original image by the scanner 200, that is, reading by the scanner is started in step S2, and plate making by the plotter unit 40, that is, plotter plate making is performed.
[0037]
In step S2, the operation of discharging the plate is monitored. When the discharging is completed, the drum drive motor 41 is driven, and the printing drum 1 is moved to the plate supply position where the clamper 5 is positioned in the vicinity of the brake roller 26 as shown in FIG. Move to wait. In the plotter unit 40, the platen roller 8 and the conveying roller pair 11 are rotationally driven in synchronization with each other, and the master 6 is pulled out from the master roll 6a. The drawn master 6 is conveyed by the platen roller 8 while being heated, melted and perforated by the thermal head 7 based on the image information. At this time, the cutting means 4 is positioned at the initial position retracted from the master conveyance path, the movable guide plate 23 is positioned at the solid line position in FIG. 6, and the brake roller 26 is positioned at the two-dot chain line position in FIG.
[0038]
The master 6 is conveyed while being made, and after passing between the guide plate 21 as the plate making master 106, the master 6 is conveyed between the movable guide plate 23 and the guide plates 24 and 25 to occupy the plate feeding position. It is sent to the clamper 5. The arrival of the master at the clamper 5 is determined from the number of steps of the stepping motor 30. When the number of steps at which the plate making master 106 reaches the clamper 5, the front end 106a of the plate making master 106 is determined to have reached the clamper 5. The clamper 5 is closed and a roller swinging means (not shown) is operated to position the brake roller 26 at the solid line position in FIG.
[0039]
Thereafter, the platen roller 8 and the conveying roller 11 continue to rotate, and the plate-making master 106 is bent at a position between the guide member 22 and the guide plate 24. When it is determined from the number of steps of the stepping motor 30 that the deflection amount has reached a predetermined amount, the drum drive motor 41 is driven to rotate at a slower speed than during printing, and the printing drum is rotated by a predetermined angle at which the deflection amount disappears. 1 is rotated in the clockwise direction of FIG. At this time, the master making master 106 having the tip 106a sandwiched by the clamper 5 rotates the brake roller 26 via a torque limiter, so that a predetermined tension is applied to the master at a portion between the clamper 5 and the brake roller 26. Is granted. That is, the plate making master 106 is wound around the drum outer peripheral surface 1 a while being tensioned by the rotation of the printing drum 1 and the brake roller 26. When the plate making master 106 is fed, the cutting means 4 is positioned at the initial position retracted from the master transport path, so that the master 6 and the plate making master 106 can be transported satisfactorily.
[0040]
In step S3 of FIG. 5, the plate making master 106 for one plate is conveyed by plate making based on the number of steps of the stepping motor 30, and the completion of the master plate feeding is determined. When the master 6 is conveyed by a predetermined number of steps from the stepping motor 30 and the plate feeding is finished, the rotation of the platen roller 8 and the conveying roller 11 is stopped and the process proceeds to step S4. In step S4, the master presence / absence detection sensor 104 determines whether or not there is a master in the printing drum 1. Here, as shown in FIG. 7, the detection light 107 is emitted from the master presence / absence detection sensor 104 toward the label unit 103. At this time, if the front end 106 a of the plate making master 106 is sandwiched between the clampers 5 and wound around the drum outer peripheral surface 1 a, the plate making master 106 is positioned on the label portion 103.
[0041]
The irradiated detection light 107 is reflected by the plate making master 106 as shown in FIG. 7, and the reflected light 108 is received by the master presence / absence detection sensor 104. For this reason, the output of the master presence / absence detection sensor 104 becomes high (Hi). When the plate making master 106 is not wound around the drum outer peripheral surface 1a, the detection light 107 is applied to the black label portion 103, so that the master presence / absence detection sensor 104 receives a small amount of reflected light 108. For this reason, the output of the master presence / absence detection sensor 104 becomes low (Lo).
[0042]
That is, if the output of the master presence / absence detection sensor 104 is low (Lo) in step S4, it is determined that there is no master on the printing drum 1, and the process proceeds to step S6, where the output of the master presence / absence detection sensor 104 is high ( In the case of Hi), it is determined that there is a master on the printing drum 1 and good plate feeding is performed, and the process proceeds to step S5.
[0043]
In steps S5 and S6, a master cut process is performed. In this master cutting process, a guide plate swinging means (not shown) is operated just before the last deflection of the plate making master 106 is eliminated by the rotation of the printing drum 1. The movable guide plate 23 is positioned at the two-dot chain line position (second position) in FIG. 6, and immediately after that, the cutter driving motor is operated to reciprocate the holder 13 at a high speed to cut the plate making master 106. .
[0044]
When the master cut process is performed in step S6, the process proceeds to step S7, and the apparatus is stopped to perform the plate feeding error process. That is, the master cut process in step S6 is a cut process for processing a master for plate making or plate feeding failure.
[0045]
When the master cutting process is performed in step S5, the process proceeds to step S8, and the winding and printing process on the drum outer peripheral surface 1a of the plate making master 106 that would have been cut to a predetermined length for one plate is executed. Therefore, the drum drive motor 41 is driven (turned on). The drum drive motor 41 in step S8 is rotationally driven at a speed lower than that during printing, and rotates the printing drum 1 at a low speed in the drum rotation direction A.
[0046]
After step S8, in step S9, it is determined whether the printing drum 1 has rotated a predetermined number of times. In this embodiment, it is determined from the detection signal of the drum position detection sensor 112 whether or not the printing drum 1 has rotated once since the front end 106a of the plate making master 106 is clamped by the clamper 5. If the printing drum 1 is rotated once, the process proceeds to step S10 to determine whether the plate making master 106 is cut to a predetermined length. This determination is made based on whether or not the master presence / absence detection sensor 104 has detected the screen leather portion 102. That is, as shown in FIG. 8, if the plate-making master 106 wound around the drum outer peripheral surface 1a is accurately cut to a predetermined length, the rear end 106b can be placed on the screen leather portion 102. Absent. Therefore, the detection light 107 emitted from the master presence / absence detection sensor 104 is reflected by the black screen leather portion 102, and the master presence / absence detection sensor 104 receives a small amount of reflected light. For this reason, the output of the master presence / absence detection sensor 104 becomes low (Lo). On the other hand, if the master making master 106 is cut longer than a predetermined length, the master making master 106 is positioned on the screen leather portion 102 as shown in FIG. Therefore, the detection light 107 emitted from the master presence / absence detection sensor 104 is reflected by the plate making master 106, and the reflected light 108 is received by the master presence / absence detection sensor 104. Therefore, the output of the master presence / absence detection sensor 104 is high (Hi). )
[0047]
In step S10, if the output of the master presence / absence detection sensor 104 is high (Hi), the process proceeds to step S12 assuming that the master making master 106 has been cut longer than a predetermined length, and the drum drive motor 41 is stopped. In S13, the notification display device 202 is ended in the notification state. The notification state here means, for example, displaying a service man call on the notification display device 202. In the case where a sound generation device is employed as the notification means, the notification state is to notify a warning buzzer or warning message by voice.
[0048]
On the other hand, if the output of the master presence / absence detection sensor 104 is low in step S10, it is determined that the plate-making master 106 has been cut to a predetermined length, and the process proceeds to step S11, where the normal printing process and printing are performed. End standby and control.
[0049]
In the normal printing process, only one sheet 61 is fed from the paper feed tray 64 shown in FIG. 2, and the press roller 48 is moved toward and away at a predetermined timing, so that the plate making wound around the press roller 48 is performed. The printing drum 1 is rotated at a low speed while the paper 61 is interposed between the masters 106, and the ink in the printing drum 1 is supplied from the punching unit 109 to the plate making master 106 to be adapted. The print standby state refers to a state in which the apparatus is temporarily stopped after the printing is finished, and an input of the number of prints from a numeric keypad (not shown) and an operation of a print start key are awaited in this embodiment.
[0050]
FIG. 4 is a diagram illustrating an output state of the master presence / absence detection sensor. In FIG. 4, when the sensor output becomes Hi at the end of the plate feeding (step S3 in FIG. 5), it is detected that the plate making master 106 is on the printing drum 1, and at least the plate feeding operation is normal. be able to. If the sensor output becomes Lo after one rotation of the drum (step S10 in FIG. 5), the master making master 106 is not positioned on the screen leather portion 102, and it is detected that the master cutting has been performed satisfactorily. Can do.
[0051]
On the other hand, if the sensor output is Lo at the end of the plate feeding (step S3 in FIG. 5), the plate making master 106 does not exist on the printing drum 1, and it is detected that the plate feeding operation is not normally performed. be able to. If the sensor output is Hi after one rotation of the drum (step S10 in FIG. 5), the master making master 106 exists on the screen leather portion 102, and it is detected that the master cut is not performed well. be able to.
[0052]
In this way, the control means 90 determines that the plate making master 106 is not a predetermined length at the time of printing performed after the plate making master 106 is wound around the drum outer peripheral surface 1a. If the position of the rear end 106b of 106 is not detected by the detecting means, the drive of the drum drive motor 41 that rotationally drives the printing drum 1 is controlled so that the master is not cut to a predetermined length. Unnecessary conveyance and excessive winding of the plate making master 106 around the drum outer peripheral surface 1a indicated by phantom lines in FIG. 9 are eliminated. For this reason, it is possible to prevent the mechanical lock that occurs when the opening / closing operation of the clamper 5 is hindered or narrowed by the master around which the printing unit 49 is wound.
[0053]
In this embodiment, the screen leather portion 102 normally provided on the printing drum 1 is used as the detected portion. However, as shown in FIG. 10, a black detection label 203 is pasted on the clamper 5 as the detected portion. Also good. In this way, if the detection label 203 provided on the clamper 5 is not detected by the drum position detection sensor 41, it can be seen that the plate making master 106 is located on the clamper 5 and hides the detection label 203. It can be detected that the length is not cut.
[0054]
In this embodiment, the thermal head 7 constituting the plate making / plate feeding means 3 is attached to the apparatus main body side plate (not shown), the platen roller 8 is attached to the cover 9, and the cover 9 is opened so that the master transport path can be opened. However, a configuration in which the thermal head 7 is attached to the cover 9 and the platen roller 8 is attached to an apparatus main body side plate (not shown) may be employed.
[0055]
In the present embodiment, the stencil printing apparatus that performs the process from discharging to printing using the characteristic part of the present invention as a printing apparatus has been described as an example. However, the printing is simply performed on the master, cut into a predetermined length, and the printing is performed. A so-called plate making apparatus may be used as a printing apparatus, and the present invention may be applied. The reason why the plate making apparatus is called a printing apparatus is that the printing is equivalent to a kind of printing.
[0056]
In this embodiment, image information is taken from the scanner 200. However, when the printing apparatus has a configuration capable of transmitting / receiving data to / from an information processing device such as a personal computer or a mobile terminal device, the information processing is performed. Image information may be fetched from a device, and plate making may be performed based on the information.
[0057]
【The invention's effect】
  According to the present invention, the master is cut to a predetermined length.Master presenceIf it is not detected by the detection means, the drive of the drive source for rotationally driving the printing drum is controlled to stop, so that unnecessary transport of the master roll and excessive winding of the master around the outer peripheral surface of the printing drum are eliminated, and the master locking means is opened and closed. It is possible to reduce defects due to defective cutting of the master, such as the occurrence of a mechanical lock in which the device is locked due to a defect or a master that has been wound many times, and the device is locked.
[0058]
According to the present invention, since the master is tensioned by the rotation of the printing drum, it becomes easy to reliably cut the master, and it is not necessary to newly provide a member for tensioning the master. Reduction and cost reduction.
[0059]
  According to the present invention,Master presenceScreen leather positioned on the downstream side in the master winding direction from the rear end of the master when the master cut to a predetermined length is wound on the outer peripheral surface of the printing drum on the detected portion constituting the detection means Therefore, it is not necessary to newly provide a detected part, and the number of parts can be reduced and the cost can be reduced.
[0060]
  According to the present invention,Master presenceThe detected part constituting one of the detection means is black,Master presenceSince the detector constituting the other of the detection means is a reflection type optical sensor, the light emitted from the optical sensor is reflected by the master when the master is cut longer than a predetermined length, and the master has a predetermined length. If it is cut to the right, it will be reflected by the black detected part, so the cut state of the master can be detected from the reflectance, and the master cut defect can be easily detected by software processing .
[0061]
According to the present invention, when the master is not a predetermined length at the time of printing, the driving source is stopped, so that unnecessary transport of the master roll and excessive winding of the master around the outer peripheral surface of the printing drum are eliminated. It is possible to reduce defects due to defective cutting of the master such as defective opening and closing of the means and occurrence of a mechanical lock in which the master wound around multiple times interferes with the printing pressure member to lock the device.
[0062]
According to the present invention, since the abnormality in the master length is notified by the notification means, the apparatus operator can accurately grasp the state of the apparatus, and can quickly cope with the state of the apparatus.
[Brief description of the drawings]
FIG. 1 is an enlarged view showing a configuration of a printing drum and a configuration of a plotter unit, which are main parts of the present invention.
FIG. 2 is a schematic view of a main part of a stencil printing apparatus showing an embodiment of the printing apparatus of the present invention.
FIG. 3 is a block diagram of a control unit of the present invention and main components connected thereto.
FIG. 4 is a diagram showing output characteristics of a master presence / absence detection sensor as a detector.
FIG. 5 is a flowchart of a control system for detecting a master cut abnormality.
FIG. 6 is an enlarged view showing a master plate supply state with respect to a printing drum occupying a plate supply position.
FIG. 7 is an enlarged view showing a state where the presence / absence of a plate making master on the drum outer peripheral surface is detected.
FIG. 8 is an enlarged view showing a state in which the detector detects the rear end position of the master.
FIG. 9 is an enlarged view showing a detection state by a detector when the master is in a state longer than a predetermined length.
FIG. 10 is a perspective view of a printing drum in which a detected portion is disposed on a master locking unit.
[Explanation of symbols]
1 Printing drum
1a Outer surface of printing drum
4 cutting means
5 Master locking means
41 Drive source
90 Control means
103 Detected part (screen leather part)
104 Detector (Reflective optical sensor)
106 Master
106a Master tip
106b Rear end of master
203 Detected part
202 Notification means
A Master winding direction

Claims (7)

Printing having a printing drum that is driven to rotate by a driving source, master locking means that is provided on the outer peripheral surface of the printing drum and that locks the leading end of the master, and cutting means that cuts the master into a predetermined length In the device
Master presence / absence detecting means for detecting the presence / absence of a master on the printing drum and detecting whether the master has been cut into a predetermined length after the presence / absence of the master;
When the master does not detect the master presence detection means that it is cut to a predetermined length, have a control means for stopping the driving of said drive source,
When the master presence / absence detecting means is cut into a predetermined length and wound around the outer peripheral surface of the printing drum, the first detected portion disposed within the master winding range of the outer peripheral surface of the printing drum A second detected portion provided on the outer peripheral surface of the printing drum where the rear end of the master is located, and the first and second detected portions disposed in the vicinity of the outer peripheral surface of the printing drum. A printing apparatus having a detector for detecting the ink. The printing apparatus according to claim 1.
The second detected portion is a screen leather positioned downstream in the master winding direction from the rear end of the master when the master cut to a predetermined length is wound around the outer peripheral surface of the printing drum. part in a printing device. Printing having a printing drum that is driven to rotate by a driving source, master locking means that is provided on the outer peripheral surface of the printing drum and that locks the leading end of the master, and cutting means that cuts the master into a predetermined length In the device
Master presence / absence detecting means for detecting the presence / absence of a master on the printing drum and detecting whether the master has been cut into a predetermined length after the presence / absence of the master;
Control means for stopping driving of the drive source when the master presence / absence detection means does not detect that the master is cut to a predetermined length;
The master presence / absence detecting means includes a first detected part arranged in a master winding range on an outer peripheral surface of the printing drum, a second detected part provided in the master locking means, and the printing A printing apparatus comprising: a detector disposed in the vicinity of the outer peripheral surface of the drum and detecting the first and second detected parts . The printing apparatus according to claim 1, 2 or 3.
The cutting device is a printing apparatus that performs a cutting operation in a state in which a leading end of the master is locked by the master locking device, and tension is applied to the master by rotation of the printing drum . The printing apparatus according to claim 1 , 2 or 3 ,
The printing apparatus, wherein the second detected portion is black, and the detector is a reflective optical sensor . The printing apparatus according to any one of claims 1 to 5 ,
The control unit determines that the master is not a predetermined length and stops driving the driving source when printing is performed after the master is wound around the outer peripheral surface of the printing drum. . The printing apparatus according to any one of claims 1 to 6,
When the control means does not detect that the master is cut to a predetermined length, the control means has notification means for notifying the master length abnormality under the control of the control means. In addition, the printing apparatus which sets the notification means to a notification state .

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