Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F7/00—Rotary lithographic machines
  • B41F7/02—Rotary lithographic machines for offset printing
  • B41F7/10—Rotary lithographic machines for offset printing using one impression cylinder co-operating with several transfer cylinders for printing on sheets or webs, e.g. satellite-printing units
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F21/00—Devices for conveying sheets through printing apparatus or machines
  • B41F21/10—Combinations of transfer drums and grippers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M1/00—Inking and printing with a printer's forme
  • B41M1/14—Multicolour printing

Definitions

• the invention relates to a method and a device for producing a multicolor print on a sheet in printing presses, in which the sheet lies more than one revolution of the printing cylinder on the printing cylinder and is printed in succession with a plurality of colors on the printing cylinder in a gripper closure.
• the printed sheet is transferred to a chain circle and placed on a delivery stack.
• DE 195 23 378 AI which includes a printing press that works on the same principle as the printing press according to US Pat. No. 5,469,787. According to the subject of DE 195 23 378 AI, a laser imaging device is provided for imaging the printing plates in the machine.
• the invention advantageously enables the field of application of a printing machine with a triple-sized printing cylinder and double-sized offset and printing form cylinder to be expanded by arranging a first and a second transfer drum, each with a gripper system, and providing the first transfer drum with a rubber blanket.
• the transfer drum can thus be used as an image transfer device and a third printing unit can be installed in the printing press for the application of further colors to the sheet.
• the transfer drum receives the print image directly from a printing form cylinder or indirectly from an offset cylinder. It is essential that the transfer drum is equipped in such a way that it can fulfill several functions (sheet transport, image transport and image transmission). The solution requires little effort since it is integrated into a printing press that can print four colors on the sheet in one pass.
• the arrangement of an application device for the second transfer drum for painting or applying another color to the sheet also increases the area of application of the printing press.
• FIG. 3 a printing machine according to FIG. 1 with an additional application device on the second transfer drum for applying ink or lacquer.
• a device for writing 1 to printing formes 3 mounted on a printing form cylinder 2 is provided.
• the printing form cylinder 2 is equipped with two active surfaces 4, each of which carries a printing form 3.
• the printing form cylinder 2 is further assigned two inking units 5 which can be switched on and off alternately.
• the printing form cylinder 2 is operatively connected to a printing cylinder 6 via an offset cylinder 9 with two surfaces.
• the printing cylinder 6 has three printing surfaces 7 and accordingly three rows of grippers 8 for gripping sheets 10 to be printed.
• the printing cylinder 6 is assigned a second formation of offset cylinder 9, printing form cylinder 2, inking unit 5 and device for writing 1.
• the pressure cylinder 6 thus has a triple size diameter.
• Printing form cylinder 2 and offset cylinder 9 have a diameter twice as large.
• Offset cylinder 9, printing form cylinder 2 and the two inking units 5 form a printing unit 30.1 to 30.3, of which, according to FIGS. 1 and 3, the first and second printing units 30.1, 30.2 are directly assigned to the printing cylinder 6.
• feed elements 12 are arranged above the feeder sheet stack.
• a feed mechanism 14 is provided for feeding the sheets 10 to be printed from the contact line 13 to the impression cylinder 6.
• a sheet discharge device 26, which consists of two transfer drums 15, 16 and the sheet delivery 25, is arranged downstream of the printing cylinder 6 for sheet removal.
• the sheet boom 25 consists of the front and rear chain deflection wheel
• the first and the second (viewed in the conveying direction of the sheet 10) transfer drum 15, 16 are each provided with a gripper system 32 for the sheet conveyance.
• Transfer drum 15, 16 corresponds to the diameter of the printing form and offset cylinder 2.9.
• the first transfer drum 15 has a closed surface in the functional area, which is covered with a rubber blanket. Printing cylinder 6 and the first transfer drum 15 have the common tangent point t 6> 15 .
• the first transfer drum 15, see FIGS. 1 and 3, is assigned the third printing unit 30.3, which has the same structure (offset cylinder 9, printing form cylinder 2, two inking units 5) as the first and second printing units 30.1, 30.2.
• the two inking units 5 per printing unit 30.1-30.3 work alternately (alternating positioning on the printing form cylinder 2), so that two colors can be applied to the sheet 10 per printing unit 30.1-30.3.
• the third printing unit 30.3 is indirectly assigned to the printing cylinder 6 (FIGS. 1 and 3) via the first transfer drum 15, which in this case fulfills the function of sheet transport, image transport and image transmission.
• the first transfer drum 15 takes over the function of the offset cylinder 9 of the third printing unit 30.3.
• the second transfer drum 16 is provided with a closed drum cap, which is designed so stable that the second transfer drum 16 can perform the function of an impression cylinder.
• the second transfer drum 16 is assigned an application device 31 for applying paint or applying another color to the sheet 10.
• the application device 31 consists of the ink fountain 24, an anilox roller 27 and an applicator roller 28, which is provided between the anilox roller 27 and the second transfer drum 16.
• the diameter of the transfer drum 16, applicator roller 28 and anilox roller 27 behaves as 2: 1: 0.5.
• the ink fountain 24 is filled with paint and the applicator roller 28 is covered with a rubber blanket.
• the ink fountain 24 is filled with ink and the application roller 28 is provided with a flexographic printing plate.
• a dryer 29 can be provided in the front chain deflection wheel 22 for drying the sheet 10.
• the mode of operation of the printing press with the invention is as follows: the sheet 10, which is separated from the feeder sheet stack 11, is conveyed by means of the elements for conveying 12 to the contact line 13 of the printing press and is transferred from the feed mechanism 14 to one of the gripper rows 8 of the printing cylinder 6. Only every second gripper row 8 passing the feed mechanism 14 is fed a sheet 10.
• the print image is applied by means of the device for writing 1 to the printing form 3 clamped on the printing form cylinder 2.
• the printing image is inked by the inking unit 5 and transferred to the offset cylinder 9, which passes the printing image onto the sheet 10 lying on the printing cylinder 6.
• the first and second colors are applied to the sheet 10 by the first and second printing units 30.1, 30.2.
• the print image is transferred to the offset cylinder 9 assigned to the first transfer drum 15. From the blanket of the offset cylinder 9, the print image is now transferred to the blanket of the first transfer drum 15 and from this at the tangent point t 6 ⁇ ⁇ 5 with a third color to the sheet 10, which is still held by the gripper row 8 of the printing cylinder 6. Thereafter, the sheet 10 lying on the printing cylinder 6 is again guided through an entire revolution of the printing cylinder 6, so that the fourth and fifth colors can be applied by the first and second printing units 30.1, 30.2.
• the sheet leading edge then reaches the tangent point t 6> 15 of the printing cylinder 6 and the first transfer drum 15, the sheet 10, which has already been provided with five ink jobs, is transferred from the printing cylinder 6 to the gripper system 32 of the first transfer drum 15. At the same time, the sixth color is transferred from the blanket of the transfer drum 15 to the sheet 10.
• the sheet 10 is then fed to the delivery chain circuit 17 via the second transfer drum 16 and deposited on the delivery sheet stack 21.
• the method steps proceed as described above with the following change. Since the first transfer drum 15 takes over the function of the offset cylinder 9, the third and sixth colors are transferred from the printing form cylinder 2 of the third printing unit 30.3 directly onto the transfer drum 15 and from there onto the sheet 10, which in turn alternately either from a gripper row 8 of the printing cylinder 6 or guided by the gripper system 32 of the transfer drum 15. Thereafter, the sheet 10 is placed on the delivery sheet stack 21 as stated.
• the sheet 10 can additionally be provided with a lacquer application or with another color and then deposited on the delivery sheet stack 21.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Rotary Presses (AREA)
• Printing Methods (AREA)
• Color, Gradation (AREA)
• Color Electrophotography (AREA)
• Impression-Transfer Materials And Handling Thereof (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=7879481

Family Applications (1)

Country Status (5)

Families Citing this family (5)

Family Cites Families (13)

• 1998
  • 1998-09-02 DE DE19839875A patent/DE19839875B4/de not_active Expired - Fee Related
• 1999
  • 1999-08-12 WO PCT/DE1999/002556 patent/WO2000013903A2/fr active IP Right Grant
  • 1999-08-12 US US09/763,613 patent/US6546862B1/en not_active Expired - Fee Related
  • 1999-08-12 EP EP99952408A patent/EP1109671B1/fr not_active Expired - Lifetime
  • 1999-08-12 AT AT99952408T patent/ATE228062T1/de not_active IP Right Cessation
  • 1999-08-12 DE DE59903485T patent/DE59903485D1/de not_active Expired - Lifetime
  • 1999-11-04 DE DE19953021A patent/DE19953021B4/de not_active Expired - Lifetime

Non-Patent Citations (1)

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