JP2013226654A - Sheet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet printer which is compact and capable of performing multicolor printing to both sides of a sheet.SOLUTION: A sheet printer 100 has a first digital printing unit 120 having a first printing drum 121 holding and transferring a sheet 1, and a first digital printer 122 performing multicolor printing to the sheet 1 held by the first printing drum 121, a second digital printing unit 150 having a second printing drum 151 holding and transferring the sheet 1 transferred from the first digital printing unit 120 and a second digital printer 152 performing multicolor printing to the sheet 1 held by the second printing drum 151, and a sheet reversing unit 140 delivering the sheet 1 from the first digital printing unit 120 side to the second digital printing unit 150 side to position the outside face of the sheet 1 when it is held on the peripheral face of the first printing drum 121 to face the inside when it is held on the peripheral face of the second printing drum 151.

Description

  The present invention relates to a sheet printer for printing a plurality of colors on a sheet.

  As a sheet printer that performs printing of a plurality of colors on both sides of a sheet, for example, a printer described in Patent Document 1 below is known. In the sheet printer described in Patent Document 1 and the like, each offset printing unit (five in this example) of the first printing unit is provided on one side of the sheet fed from the sheet feeding unit. After offset printing of inks of different colors, the front and back of the sheet are reversed by a sheet reversing unit, and each offset printing unit of the second printing unit (five in this example) with respect to the other surface of the sheet However, it is possible to print a plurality of colors (five colors in this example) on both sides of the sheet by offset printing inks of different colors and discharging them to the sheet discharge unit.

JP 2009-061776 A JP 2002-011847 A JP 59-0119155 A

  In the sheet printer described in Patent Document 1 and the like, a first printing unit that performs printing of a plurality of colors on one surface of a sheet and a second printing that performs printing of a plurality of colors on the other surface of the sheet Since it is necessary to provide offset printing units for each color (total of 10 units) in both sections, the length from the sheet supply unit to the sheet discharge unit becomes very long, resulting in difficulty in securing the installation space. It was.

  In view of the above, an object of the present invention is to provide a sheet printer capable of printing a plurality of colors on both sides of a sheet while being compact.

  In order to solve the above-described problems, a sheet printing machine according to the present invention includes a first printing cylinder that holds and conveys a sheet on an outer peripheral surface, and the outer periphery of the first printing cylinder. A first digital printing unit having a first digital printing device that performs printing of a plurality of colors on the outer surface of the sheet, and the sheet conveyed from the first digital printing unit is held on the outer peripheral surface and conveyed Second digital printing means comprising: a second printing cylinder that performs printing; and a second digital printing device that performs printing of a plurality of colors on the outer surface of the sheet held on the outer peripheral surface of the second printing cylinder. And the first digital printing means and the second digital printing means arranged between the first digital printing means and held on the outer peripheral surface of the first printing cylinder of the first digital printing means. The second digital printing hand on the outer surface of the sheet Sheet reversing means for delivering the sheet from the first digital printing means side to the second digital printing means side so that the sheet is positioned inside when held on the outer peripheral surface of the second printing cylinder. It is characterized by having.

  In the sheet printer according to the present invention, the first printing cylinder of the first digital printing unit and the second printing cylinder of the second digital printing unit may be the above-described sheet printing machine. Each has a gripper device for gripping the leading end of the sheet in the transport direction, and the sheet reversing means grips the end on the trailing side of the sheet in the transport direction from the first digital printing means. In addition, a reversing cylinder having a switching gripper device that transfers the gripped end of the sheet to the second digital printing means side with the conveyance direction leading side is provided.

  Further, the sheet printer according to the present invention is the above-described sheet printer, wherein the switching gripper device of the reversing cylinder of the sheet reversing unit is arranged in the direction of conveyance of the sheet from the first digital printing unit side. It is possible to switch between gripping of the end on the row side and gripping of the end on the leading side in the transport direction.

  In the sheet printer according to the present invention, the first digital printing device of the first digital printing unit and the second digital printing device of the second digital printing unit may be the above-described sheet printing machine. Ink jet type or electrophotographic type.

  The sheet printer according to the present invention is the sheet printer described above, wherein the sheet printer is disposed between the first digital printing unit and the sheet reversing unit, and the first digital printing unit includes the first digital printing unit. A first coater that coats the outer surface of the sheet when held on the outer peripheral surface of the printing cylinder; and a second coater disposed downstream of the second digital printing unit in the sheet conveying direction. And a second coater for coating the outer surface of the sheet when held on the outer peripheral surface of the second printing cylinder of the digital printing means. And

  According to the sheet printer according to the present invention, it is possible to print a plurality of colors on both sides of the sheet while being compact.

It is a schematic block diagram of 1st embodiment of the sheet printer concerning this invention. FIG. 3 is an explanatory diagram of the operation of a reversing cylinder when printing on both sides of a sheet in the sheet printer of FIG. 1. FIG. 3 is an explanatory diagram of an operation of the reversing cylinder when printing is performed only on one surface of the sheet in the sheet printer of FIG. 1. It is a schematic block diagram of 2nd embodiment of the sheet printer concerning this invention. It is a schematic block diagram of the principal part of other embodiment of the sheet printer concerning this invention.

  Embodiments of a sheet printer according to the present invention will be described with reference to the drawings. However, the sheet printer according to the present invention is not limited to only the following embodiments described with reference to the drawings.

<First embodiment>
A first embodiment of a sheet printer according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, a sucker device 113 for feeding the sheets 1 to the feeder board 112 one by one is disposed above the sheet feed table 111 on which the sheets 1 are stacked. The front end side of the feeder board 112 is in the vicinity of a so-called single cylinder transfer cylinder 101 having a pair of gripping claw devices 101a for detachably holding the end (one end) on the leading side in the conveyance direction of the sheet 1 Is located. Between the front end side of the feeder board 112 and the transfer cylinder 101, a swing device 114 for transferring the sheet 1 on the feeder board 112 to the transfer cylinder 101 is disposed.

  The transfer cylinder 101 includes a first printing cylinder 121 of a so-called double cylinder having two sets of gripping claw devices 121a for detachably holding an end (one end) on the leading side in the conveyance direction of the sheet 1. It is in contact. An ink jet first digital printing device 122 is disposed downstream of the contact position of the first printing cylinder 121 with the transfer cylinder 101 in the rotation direction (sheet 1 conveyance direction). The first digital printing device 122 is disposed so as to face the outer peripheral surface of the sheet 121, and the outer surface of the sheet 1 held on the outer peripheral surface of the first printing cylinder 121 is A plurality of colors (four colors in the present embodiment) can be digitally printed by the inkjet method.

  On the downstream side in the rotation direction (the conveyance direction of the sheet 1) of the first printing cylinder 121 from the position facing the first digital printing device 122, the end (one side of the conveyance direction of the sheet 1) A so-called single cylinder transfer cylinder 102 having a pair of gripping claw devices 102a for detachably gripping the end portion) is in contact with it. The transfer cylinder 102 has two sets of gripper devices 141a for detachably holding the end (one end) on the leading side in the transport direction of the sheet 1 and the end on the trailing side in the transport direction of the sheet 1 A so-called double cylinder suction cylinder 141 having two sets of suction devices 141b capable of sucking and holding (the other end) is in contact with each other.

  The suction cylinder 141 has a switching claw device that detachably holds an end (one end) on the leading side in the conveyance direction of the sheet 1 or an end (end on the other side) on the trailing side in the conveyance direction. A so-called single cylinder reversing cylinder 142 having a pair of 142a is in contact, and the switching gripping claw device 142a is, for example, a reversing mechanism for reversing the front and back of the sheet 1 as described in Patent Document 2 and the like. It has become.

  The reversing cylinder 142 is a second printing of a so-called double cylinder having two sets of gripping claw devices 151a for detachably gripping the end (the other side or one end) of the sheet 1 in the transport direction. The body 151 is in contact. An ink jet second digital printing device 152 is disposed downstream of the contact position of the second printing cylinder 151 with the reversing cylinder 142 in the rotation direction (sheet 1 conveyance direction). The second digital printing device 152 is disposed so as to face the outer peripheral surface of the sheet 151, and the second digital printing device 152 is disposed on the outer surface of the sheet 1 held on the outer peripheral surface of the second printing cylinder 151. A plurality of colors (four colors in the present embodiment) can be digitally printed by the inkjet method.

  On the downstream side in the rotation direction (sheet 1 conveyance direction) of the second printing cylinder 151 from the position facing the second digital printing device 152, the end (the other side or the other side) of the sheet 1 conveyance direction is located downstream. A so-called single-ply paper take-up cylinder 171 having a pair of gripping claw devices 171a for detachably gripping one end portion) is in contact with it. The paper drum 171 communicates with the upstream side in the traveling direction (sheet 1 conveyance direction) of the sheet discharge belt 172 that receives and conveys the sheet 1 from the paper drum 171. The downstream side of the sheet discharge belt 172 in the running direction (the conveyance direction of the sheet 1) is in contact with a discharge table 173 on which the sheets 1 are stacked.

  In the present embodiment, the sheet feeding unit 111, the feeder board 112, the sucker device 113, the swing device 114, and the like constitute a sheet feeding unit 110 serving as a sheet feeding unit, and the first printing cylinder. 121, the first digital printing device 122 or the like constitutes the first digital printing unit 120 as the first digital printing means, and the suction cylinder 141 or the reversing cylinder 142 or the like serves as a sheet reversing means. The reversing unit 140 is configured, and the second printing cylinder 151, the second digital printing device 152, and the like constitute a second digital printing unit 150 that is a second digital printing unit, and the paper drum 171. , The sheet discharge belt 172, the sheet discharge table 173, and the like, the sheet discharge unit 170 as sheet discharge means. The transfer cylinder 101, 102, the sheet supply unit 110, the first digital printing unit 120, the sheet reversing unit 140, the second digital printing unit 150, the sheet discharging unit 170, etc. The machine 100 is configured.

  Next, the operation of the sheet printer 100 according to this embodiment will be described.

  When the sheets 1 on the sheet feeding table 111 of the sheet supply unit 110 are fed one by one onto the feeder board 112 by the sucker device 113, the swing device 114 is conveyed to the gripping claw device 101 a of the transfer cylinder 101 in the conveying direction of the sheet 1. Hand over the leading edge (one edge).

  The sheet 1 held on the outer peripheral surface of the transfer cylinder 101 with the end (one end) on the conveyance direction leading side held by the gripping claw device 101a of the transfer cylinder 101 is An end portion (one end portion) is gripped and replaced by the gripper device 121a of the first printing cylinder 121 of the first digital printing unit 120, whereby the first printing cylinder 121 is replaced. The outer surface (one surface) is digitally printed in batch by the first digital printing device 122 using the ink jet method, and then transported. An end portion on the direction leading side (one end portion) is replaced with the holding claw device 102 a of the transfer drum 102.

  The sheet 1 held on the outer peripheral surface of the transfer cylinder 102 with the end (one end) on the conveyance direction leading side held by the gripping claw device 102a of the transfer cylinder 102 is An end (one end) is gripped and replaced by the gripping claw device 141a of the suction drum 141 of the sheet reversing unit 140, and an end (the other end) in the transport direction Part) is held on the outer peripheral surface of the suction drum 141 by being sucked and held by the suction device 141b of the suction drum 141.

  Then, an end portion (one end portion) on the leading side in the conveyance direction of the sheet 1 held on the outer peripheral surface of the suction drum 141 passes through the contact position between the suction drum 141 and the reversal drum 142 as it is. When the end of the sheet 1 in the conveying direction (the other end) reaches the contact position between the suction cylinder 141 and the reversing cylinder 142, the switching gripper device of the reversing cylinder 142 142a grips an end portion (the other end portion) on the trailing side in the conveyance direction of the sheet 1, and the suction drum 141 releases the sheet 1 from being held by the gripping claw device 141a and the suction device 141b. (See FIG. 2).

  As a result, the end portion (the other end portion) that has been positioned so far on the trailing side in the conveyance direction of the sheet 1 is gripped by the switching gripping claw device 142a of the reversing cylinder 142 and replaced. Thus, the suction cylinder 141 is reversed while the end portion newly positioned on the transport direction leading side, that is, the end portion positioned on the transport direction leading side and the end portion positioned on the trailing side in the transport direction are reversed. By holding the outer surface of the reversing cylinder 142 so that the outer surface (one surface) is held outside as it is, the front and back surfaces are reversed (detailed operating mechanism). (See Patent Document 2).

  In this way, the sheet 1 reversely gripped by the switching gripper device 142a of the reversing cylinder 142 has an end portion (the other end portion) newly positioned on the leading side in the conveying direction, the second digital portion. The second printing cylinder 151 of the printing unit 150 is held on the outer peripheral surface of the second printing cylinder 151 by being held by the holding claw device 151 a and is replaced by the second digital printing apparatus 152. After the outer surface (the other surface) is digitally printed in a batch with a plurality of colors (four colors in this embodiment) by the inkjet method, the end on the transport direction leading end (the other end) is the sheet. The paper catching drum 171 of the discharge unit 170 is replaced with the gripper claw device 171a.

  The sheet 1 held on the paper drum 171 is transferred to the sheet discharge belt 172 and discharged onto the sheet discharge table 173, whereby both sides are printed in multicolor.

  When printing on only one surface of the sheet 1, the sheet reversing unit 140 is arranged so that the sheet 1 is held on the outer peripheral surface of the transfer cylinder 102 on the front end side (one side) of the sheet 1. Is held by the gripping claw device 141a of the suction drum 141 and held on the outer peripheral surface of the suction drum 141, and then the sheet 1 is moved in the transport direction leading side. When the end portion (one end portion) reaches the contact position between the suction drum 141 and the reversing drum 142, the switching gripper device 142a of the reversing drum 142 is on the leading side in the conveyance direction of the sheet 1. The gripping claw device 141a of the suction drum 141 releases the gripping of the leading end (one end) in the conveying direction of the sheet 1 (the one end). (See FIG. 3).

  As a result, the reversing cylinder 142 is configured to reverse the end (one end) in the transport direction of the sheet 1 and the end (the other end) on the trailing side in the transport direction without reversing the end. The sheet 1 is replaced with the suction cylinder 141, and the surface (one surface) opposite to the surface (the other surface) located outside when the sheet 1 is held on the outer peripheral surface of the suction cylinder 141 is the outer side. Is held on the outer peripheral surface so as to be positioned at

  The sheet 1 held by the switching gripper device 142 a of the reversing cylinder 142 has an end portion (one end portion) on the leading side in the conveyance direction, and the second digital printing unit 150 has the second end portion. The printing cylinder 151 is held on the outer peripheral surface of the second printing cylinder 151 by being held and replaced by the holding claw device 151a. Surface) is an inkjet system and a plurality of colors (four colors in the present embodiment) are further digitally printed, and then the leading end (one end) in the transport direction is the paper of the sheet discharge unit 170. By replacing the gripper 171 with the gripping claw device 171a and discharging it onto the sheet discharge table 173 via the sheet discharge belt 172, printing on a plurality of colors on only one surface is performed. Is performed.

  In other words, the conventional sheet printing machine has each color for both the first printing unit that performs printing of multiple colors on one side of the sheet and the second printing unit that performs printing of multiple colors on the other side of the sheet. Offset printing units (a total of 10 units) are provided to print a plurality of colors on both sides of the sheet. In the sheet printer 100 according to the present embodiment, the first digital printing unit 120 includes the first A plurality of colors are collectively digitally printed by the first digital printing device 122 on the outer surface (one surface) of the sheet 1 held by the printing cylinder 121, and the second printing cylinder of the second digital printing unit 150 is used. A plurality of colors are digitally printed on the outer surface (the other surface) of the sheet 1 held at 151 by the second digital printing device 152 so that a plurality of colors are printed on both surfaces of the sheet 1. It was was.

  For this reason, in the sheet printer 100 according to the present embodiment, the length from the sheet supply unit 110 to the sheet discharge unit 170 can be shortened, and the installation space can be easily secured.

  Therefore, according to the sheet printer 100 according to the present embodiment, a plurality of colors can be printed on both sides of the sheet 1 while being compact.

  Further, since the delivery of the sheet 1 in the units 120, 140, 150 is performed via the gripping claw devices 121a, 141a, 142a, 151a of the cylinders 121, 141, 142, 151, the sheet 1 In addition to improving the registration accuracy of printing on one side and the other side, high-speed printing is possible and productivity can be improved.

<Second Embodiment>
A second embodiment of the sheet printer according to the present invention will be described with reference to FIG. In addition, about the part similar to 1st embodiment mentioned above, by using the code | symbol similar to the code | symbol used in description of 1st embodiment mentioned above, in 1st embodiment mentioned above, A description overlapping with the description is omitted.

  As shown in FIG. 4, the transfer cylinder 102 serving as a conveyance cylinder has two sets of gripping claw devices 231 a that detachably grip the end (one end) on the preceding side in the conveyance direction of the sheet 1. The first coater cylinder 231 of the double cylinder is in contact. A first anilox roller in which a plurality of concave cells are formed on the outer peripheral surface on the downstream side in the rotation direction (the conveyance direction of the sheet 1) from the position where the first coater cylinder 231 contacts the transfer cylinder 102. 232 is in contact. A first coater chamber 233 for supplying varnish, which is a liquid, to the cells of the first anilox roller 232 is in contact with the outer peripheral surface of the first anilox roller 232.

  A first drying device 234 for drying the varnish is disposed downstream of the contact position of the first coater cylinder 231 with the first anilox roller 232 in the rotation direction (sheet 1 conveyance direction). It is arranged so as to face one coater cylinder 231.

  On the downstream side in the rotation direction (the conveyance direction of the sheet 1) of the first coater cylinder 231 facing the first drying device 234, an end (one side end) on the preceding side in the conveyance direction of the sheet 1 A so-called single cylinder transfer cylinder 203 having a pair of gripping claw devices 203a for detachably gripping the component). The suction drum 141 of the sheet reversing unit 140 is in contact with the transfer drum 203.

  The conveyance direction of the sheet 1 is downstream in the rotation direction (the conveyance direction of the sheet 1) of the second digital printing unit 150 from the position where the second printing cylinder 151 faces the second digital printing device 152. A transfer cylinder 204, which is a so-called single cylinder transfer cylinder, having a set of gripping claw devices 204a for detachably holding the leading end (the other or one end) is in contact.

  The transfer cylinder 204 has a second coater cylinder 261 of a so-called double cylinder having two sets of gripping claw devices 261a for detachably holding an end (the other side or one side) of the sheet 1 in the conveyance direction. It is in contact. A second anilox roller in which a plurality of concave cells are formed on the outer peripheral surface on the downstream side in the rotation direction (the conveyance direction of the sheet 1) from the position where the second coater cylinder 261 contacts the transfer cylinder 204. 262 is in contact. A second coater chamber 263 that supplies liquid varnish to the cells of the second anilox roller 262 is in contact with the outer peripheral surface of the second anilox roller 262.

  A second drying device 264 for drying the varnish is opposed to the second coater cylinder 261 on the downstream side in the rotational direction from the position where the second coater cylinder 261 is in contact with the second anilox roller 262. It is arranged in this way. The paper take-up drum 171 of the sheet discharge unit 170 is in contact with the second coater drum 261 on the downstream side in the rotational direction (the conveyance direction of the sheet 1) from the position facing the second drying device 264. Yes.

  In this embodiment, the first coater device is constituted by the first anilox roller 232, the first coater chamber 233, etc., and the first coater device and the first coater cylinder 231 are formed. A first coater unit 230 as a first coater means is constituted by the first drying device 234 and the like, and a second coater is constituted by the second anilox roller 262 and the second coater chamber 263 and the like. The second coater cylinder 261, the second drying apparatus 264, and the like constitute a second coater unit 260 as a second coater means, and the transfer cylinders 101, 102, 203, and 204 are configured. The sheet supply unit 110, the first digital printing unit 120, the sheet reversing unit 140, the second digital printing unit 15 The sheet ejection unit 170, the first coater unit 230, by such the second coater unit 260 constitute a sheet printing machine 200.

  That is, the sheet printer 200 according to this embodiment is different from the sheet printer 100 according to the above-described embodiment in that the first coater is disposed between the first digital printing unit 120 and the sheet reversing unit 140. A unit 230 is disposed, and the second coater unit 260 is disposed between the second digital printing unit 150 and the sheet discharge unit 170.

  In such a sheet printer 200 according to the present embodiment, as in the case of the first embodiment described above, the first digital printing unit 120 is supplied from the sheet supply unit 110 via the transfer cylinder 101. The sheet 1 is held on the outer peripheral surface of the first printing cylinder 121, and the first digital printing device 122 uses the ink jet method on the outer surface (one surface) of the sheet 1 (in this embodiment, multiple colors). When the sheet 1 is replaced with the transfer cylinder 102 after the four colors are digitally printed, the holding claw device 231a of the first coater cylinder 231 of the first coater unit 230 is moved to the sheet 1 The sheet 1 is held on the outer peripheral surface of the first coater cylinder 231 by gripping and changing the end portion (one end portion) on the leading side in the conveying direction. .

  The sheet 1 held on the outer peripheral surface of the first coater cylinder 231 by holding the end (one end) on the leading side in the conveyance direction by the gripper claw device 231a of the first coater transfer cylinder 231 is as follows. The varnish in the first coater chamber 233 is coated on the outer surface (one surface) via the first anilox roller 232, dried by the first drying device 234, and then conveyed. An end portion on one side in the direction (one end portion) is replaced with the holding claw device 203a of the transfer drum 203.

  The sheet 1 held on the outer peripheral surface of the transfer drum 203 by holding the end portion (one end portion) on the leading side in the conveying direction by the holding claw device 203a of the transfer drum 203 and replacing it. As in the case of the first embodiment described above, the sheet is held on the outer peripheral surface of the suction drum 141 of the sheet reversing unit 140 and is positioned so far on the trailing side in the conveying direction by the reversing drum 142. The end portion (the other end portion) that has been located is newly positioned on the transport direction leading side, that is, the end portion that is positioned on the transport direction leading side and the end portion that is positioned on the trailing side in the transport direction are At the same time, it is held on the outer peripheral surface of the reversing cylinder 142 so that the surface (one surface) located outside when held on the outer peripheral surface of the suction cylinder 141 is positioned on the outer side as it is. .

  In this way, the sheet 1 reversely gripped by the switching gripper device 142a of the reversing cylinder 142 is the same as that of the first embodiment described above, in the second digital printing unit 150. A plurality of colors (four colors in the present embodiment) are digitally collected by an ink jet method on the outer surface (the other surface) by the second digital printing device 152 held by the outer peripheral surface of the second printing cylinder 151. After printing, the end portion (the other end portion) on the transport direction leading side is replaced with the gripping claw device 204a of the transfer drum 204.

  The sheet 1 held on the outer peripheral surface of the transfer cylinder 204 with the end (the other end) on the conveyance direction leading side held by the holding claw device 204a of the transfer cylinder 204 is the end on the conveyance direction preceding side. The outer portion of the second coater cylinder 261 is held and replaced by the holding claw device 261a of the second coater cylinder 261 of the second coater unit 260. The varnish in the second coater chamber 263 is coated on the outer surface (the other surface) via the second anilox roller 262 and dried by the second drying device 264. After that, the leading end (the other end) in the conveying direction is replaced with the gripping claw device 171a of the paper take-up cylinder 171 of the sheet discharge unit 170.

  The sheet 1 held on the paper drum 171 is transferred to the sheet discharge belt 172 and discharged onto the sheet discharge table 173, whereby a plurality of colors are printed on both sides and a varnish. Is coated.

  In the case where a plurality of colors and varnish coating are applied to only one surface of the sheet 1, the sheet reversing unit 140 is operated in the same manner as in the above-described embodiment. A plurality of colors and varnish coating can be applied only to the surface.

  That is, in the sheet printer 200 according to the present embodiment, varnish coating can be applied to both surfaces of the sheet 1 simultaneously with printing of a plurality of colors on both surfaces of the sheet 1.

  Therefore, according to the sheet printer 200 according to the present embodiment, it is possible to obtain the same effect as that in the first embodiment described above, and it is also possible to print a plurality of colors on both sides of the sheet 1. And varnish coating can be performed in one pass, so that the working efficiency can be improved and the productivity can be increased.

<Other embodiments>
In the above-described embodiment, the case where the digital printing units 120 and 150 in which the ink jet type digital printing devices 122 and 152 are disposed so as to face the outer peripheral surfaces of the printing cylinders 121 and 151 is described. However, as another embodiment, for example, as shown in FIG. 5, an imaging device such as a photosensitive drum 322 a or 352 a and a light emitting diode (LED) array or a semiconductor laser that scans and exposes the photosensitive drum 322 a or 352 a. 322b, 352b, developing devices 322c, 352c for attaching toner to the exposed photosensitive drums 322a, 352a, and the photosensitive drum 322a with respect to the sheet 1 held on the outer peripheral surface of the printing cylinder 121, 151. , 352a, transfer rollers 322d, 352 for transferring the toner. And the like, for each color (four colors in this embodiment), the first digital printing unit 320 or the second digital printing device 320 provided with the first digital printing device 322 or the second digital printing device 352 of the electrophotographic method. It is also possible to apply the digital printing apparatus 350.

  In the above-described embodiment, the case where the sheet reversing unit 140 for reversing the sheet 1 by the suction drum 141 and the reversing drum 142 as described in the Patent Document 2 is described. As an embodiment of the present invention, for example, a sheet reversing unit that reverses a sheet only by a reversing cylinder as described in Patent Document 3 or the like can be applied.

  In the second embodiment described above, the case where one transfer cylinder 102, 204 is provided between the digital printing unit 120, 150 and the coater unit 230, 260 has been described. As an embodiment, for example, three or more odd-numbered conveyance cylinders may be provided between the digital printing units 120 and 150 and the coater units 230 and 260.

  In the second embodiment described above, the first coater unit 230 is disposed between the first digital printing unit 120 and the sheet reversing unit 140, and the second digital printing is performed. The second coater unit 260 is disposed between the unit 150 and the sheet discharge unit 170. As another embodiment, for example, the first coater unit 230 and the second coater unit are provided. It is also possible to dispose one of 260 and omit the other.

  Although the sheet printer according to the present invention is compact, it can print a plurality of colors on both sides of the sheet, and thus can be used extremely beneficially in the printing industry and the like.

DESCRIPTION OF SYMBOLS 1 Sheet 100 Sheet printer 101,102 Transfer cylinder 101a, 102a Holding nail device 110 Sheet supply unit 111 Paper feed stand 112 Feeder board 113 Sucker device 114 Swing device 120 First digital printing unit 121 First printing cylinder 121a Holding nail Device 122 First digital printing device 140 Sheet reversing unit 141 Suction cylinder 141a Holding nail device 141b Suction device 142 Reversing cylinder 142a Switching holding nail device 150 Second digital printing unit 151 Second printing cylinder 151a Holding nail device 152 Second Digital printing apparatus 170 sheet discharge unit 171 paper take-up cylinder 171a gripping claw device 172 sheet discharge belt 173 discharge tray 200 sheet printer 203, 204 transfer cylinder 203a, 204a gripping claw device 30 1st coater unit 231 1st coater drum 231a gripper device 232 1st anilox roller 233 1st coater chamber 234 1st drying device 260 2nd coater unit 261 2nd coater drum 261a 262 Second anilox roller 263 Second coater chamber 264 Second drying device 320 First digital printing unit 322 First digital printing device 322a Photosensitive drum 322b Imaging device 322c Developer 322d Transfer roller 350 Second digital Printing unit 352 Second digital printing device 352a Photosensitive drum 352b Imaging device 352c Developer 352d Transfer roller

Claims (5)

A first printing cylinder that holds and conveys a sheet on the outer peripheral surface, and a first digital printing apparatus that performs printing of a plurality of colors on the outer surface of the sheet held on the outer peripheral surface of the first printing cylinder A first digital printing means comprising:
A second printing cylinder that holds and conveys the sheet conveyed from the first digital printing means on an outer peripheral surface; and an outer surface of the sheet that is held on the outer peripheral surface of the second printing cylinder. A second digital printing means having a second digital printing device for performing printing of a plurality of colors;
The sheet when disposed on the outer peripheral surface of the first printing cylinder of the first digital printing means disposed between the first digital printing means and the second digital printing means. When the sheet is placed on the second digital printing means side from the first digital printing means side so that the outer surface is positioned inside when held on the outer peripheral surface of the second printing cylinder of the second digital printing means. And a sheet reversing means for delivering to the printing means side. In the sheet printer according to claim 1,
The first printing cylinder of the first digital printing means and the second printing cylinder of the second digital printing means each have a gripping claw device for gripping an end portion on the preceding side in the sheet conveyance direction. With
The sheet reversing unit grips an end portion on the trailing side in the conveyance direction of the sheet from the first digital printing unit side, and sets the end portion of the grasped sheet to a leading side in the conveyance direction to the second side. A sheet printing machine comprising a reversing cylinder having a switching gripper device to be transferred to the digital printing means side. In the sheet printer according to claim 2,
The switching gripping claw device of the reversing cylinder of the sheet reversing unit includes gripping of an end on the trailing side in the transport direction of the sheet and gripping of an end on the leading side in the transport direction from the first digital printing unit side. A sheet printer characterized by being capable of switching. In the sheet printer according to claim 3,
Sheet printing, wherein the first digital printing device of the first digital printing means and the second digital printing device of the second digital printing means are of an ink jet type or an electrophotographic type Machine. In the sheet printer according to claim 4,
The outer surface of the sheet when disposed between the first digital printing means and the sheet reversing means and held on the outer peripheral surface of the first printing cylinder of the first digital printing means. A first coater means for coating the
Coating on the outer surface of the sheet when disposed on the downstream side in the sheet conveying direction of the second digital printing means and held on the outer peripheral surface of the second printing cylinder of the second digital printing means A sheet printing machine comprising: at least one of a second coater for applying

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