JP6384987B2 - Sheet-fed printing press - Google Patents

Description

  The present invention relates to a sheet-fed printing press.

  A printing machine that includes a sheet supply unit, a printing unit including a plurality of printing units, and a sheet discharge unit, and that prints a desired pattern on a sheet (for example, paper) as a printing object, includes a plurality of printing units. A transfer cylinder is arranged between the sheet and the sheet is moved from the impression cylinder of the printing unit on the upstream side in the sheet conveying direction to the impression cylinder of the printing unit on the downstream side through the nail device. Yes.

  In such a printing machine, a printing cylinder that prints on a thin sheet generally employs a solid cylinder (cylinder cylinder) as a transfer cylinder, whereas printing is performed on a thick sheet. The printing machine uses a skeleton-type cylinder (a cylinder released outside the cylinder without covering the cylinder space other than the claw device) as a transfer cylinder so that a strong sheet will not be bent greatly Has been devised.

  And the skeleton type cylinder as described above is employed in a printing machine (printing machine that prints on a sheet conveyed on the upper side of the impression cylinder) in which an ink unit is disposed above the impression cylinder, Prevents the sheet from being exposed while the sheet is transferred from the impression cylinder on the upstream side in the sheet conveyance direction to the transfer cylinder and then passed through the lower part of the transfer cylinder to the impression cylinder on the downstream side in the sheet conveyance direction. Therefore, it is known that an air guide is provided below the skeleton-type cylinder so as to face the cylinder peripheral surface of the skeleton-type cylinder (for example, see Patent Documents 1 and 2 below).

  On the other hand, some printing presses include an ink unit below the impression cylinder and print on the lower surface of the sheet conveyed under the impression cylinder (see, for example, Patent Documents 3 and 4 below). Such a printing machine has the advantage that it is not necessary to manage the drop of ink or the like onto the sheet, and each cylinder of the printing unit can be operated from the floor.

  In this type of printing machine, printing has been performed only for thin sheets so far, but maintenance is easy as described above, and it is easy to secure space for operating each cylinder of the printing unit. In recent years, there has been a demand for printing on various sheets such as a thick sheet as well as a thin sheet with such a printing machine.

Japanese Utility Model Publication No. 63-139931 JP 2004-99314 A JP 2000-62134 A JP 2013-86437 A

  However, in the printing press having the ink unit below the impression cylinder as described above, the sheet is conveyed from the lower side of the impression cylinder to the lower side of the next impression cylinder through the upper side of the impression cylinder. However, there is a problem that the trailing edge of the sheet in the conveyance direction is lowered when the sheet is being conveyed, and the printing surface tends to come into contact with the circumferential surface of the transfer cylinder. There was a problem that scratches and rubbing were liable to occur in contact with the circumferential surface of the trunk.

  For this reason, the present invention realizes stable sheet conveyance and enables scratches or rubbing on the printing surface even when printing on various sheets with a printing machine having an ink unit below the impression cylinder. An object of the present invention is to provide a sheet-fed printing press capable of suppressing the occurrence of the above.

A sheet-fed printing press according to a first invention for solving the above-described problems is
A printing means for holding the leading end side of the sheet in the conveyance direction and conveying the sheet below the cylinder circumferential surface to print the sheet; and a leading end side in the conveyance direction of the sheet that receives the sheet from the impression cylinder In a sheet-fed printing press equipped with a transfer cylinder that holds a sheet and conveys a sheet on the upper side of the cylinder,
The transfer drum is a skeleton-type drum,
An in-cylinder air discharge means for discharging air toward the radially outer side with respect to the rotation axis of the transfer cylinder, which is provided at the core of the transfer cylinder ;
Air is discharged toward the printed sheet provided opposite to the sheet conveying surface of the impression cylinder on the lower side of the impression cylinder and on the side of the sheet transfer position from the impression cylinder to the transfer cylinder. A pressure drum lower air discharge means;
A transfer cylinder upper air suction means for sucking air is provided on the upper side of the transfer cylinder so as to face a trajectory accompanying the rotation of the transfer cylinder .

A sheet-fed printing press according to a second invention for solving the above-mentioned problems is a sheet-fed printing press according to the first invention,
Air is discharged toward the sheet conveyed by the transfer cylinder from both sides in the rotation axis direction of the transfer cylinder and from the inside in the radial direction with respect to the rotation axis, above the sheet transfer position from the impression cylinder to the transfer cylinder. A crossing upper air discharge means is provided.

A sheet-fed printing press according to a third invention for solving the above-mentioned problems is a sheet-fed printing press according to the first or second invention,
A crossing lower air discharge means is provided for discharging air from below the crossing drum between the crossing drum and the sheet.

  According to the above-described sheet-fed printing press according to the present invention, even when printing on various types of sheets with a printing press provided with an ink unit below the impression cylinder, the sheets are conveyed and printed with stable behavior. It is possible to prevent the surface from being scratched or rubbed.

1 is a schematic configuration diagram of a sheet-fed printing press according to an embodiment of the present invention. It is a principal part enlarged view of FIG. It is the III-III arrow line view of FIG.

  Hereinafter, the details of the sheet-fed printing press according to the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.

  As shown in FIG. 1, the sheet-fed printing press according to the present embodiment is used for multicolor printing, and includes a sheet supply unit 1 that supplies a sheet 5 as a printing material, and a printing unit that performs printing on the sheet 5. 2, a sheet discharge unit 3 that discharges the printed sheet 5, and other accessory devices.

  The sheet supply unit 1 is provided with upper and lower two stacking platforms 6a and 6b for stacking a large number of sheets 5, and the sheets 5 on the upper stacking platform 6a are sucked one by one by a sucker device (not shown). Are fed onto the feeder board 7, and the impression cylinder 10 and the rubber cylinder 16 of the printing unit 2 a of the first color (the most upstream offset printing unit) of the printing unit 2 are fed by the swing device 8 through the paper feeding cylinder (transfer cylinder) 9. It is designed to supply during

  The printing unit 2 includes four printing units 2 a to 2 d for printing a predetermined color pattern on the lower surface of the sheet 5 supplied between the impression cylinder 10 and the rubber cylinder 16. Each of the printing units 2a to 2d has a rubber cylinder 16, an impression cylinder 10 having a diameter twice as large as the rubber cylinder 16 in contact with the rubber cylinder 16, an ink fountain device 13, and a roller group 14 including a number of rollers. And an ink unit 12 for supplying ink to the plate cylinder 11 in contact with the rubber cylinder 16. The impression cylinder 10 holds the front end side in the conveyance direction of the sheet 5 and conveys the sheet 5 below the peripheral surface of the impression cylinder 10.

A single transfer cylinder 20 is interposed between the impression cylinders 10 of the adjacent printing units 2a to 2d, and the transfer cylinder 20 has the following configuration.
That is, as shown in FIGS. 2 and 3, in this embodiment, the transfer drum 20 is a skeleton-type drum, and the two claw devices 20a are arranged opposite to each other with the shaft center therebetween, and other than the claw device 20a. The trunk circumferential space is uncovered and is released outside the trunk (that is, does not have a cylindrical sheet conveyance surface). The claw device 20 a of the transfer cylinder 20 receives the sheet 5 conveyed by the impression cylinder 10 and conveys the sheet 5 on the upper side of the peripheral surface of the transfer cylinder 20 while holding the front end side of the sheet 5 in the conveyance direction.

  The transfer cylinder 20 is provided with a cylinder air discharge device 21, a transfer drum upper air suction device 22, a transfer drum upper air discharge device 23, and a transfer drum lower air discharge device 24. In FIG. 2, a reference numeral 25 indicated by a one-dot chain line is a trajectory accompanying the rotation of the transfer drum 20 (a surface corresponding to a cylindrical sheet conveyance surface; hereinafter referred to as a transfer drum rotation trajectory).

  The trunk air discharge device 21 is provided on the trunk of the transfer drum 20, specifically, on the outside of the claw holding member 20 b that holds the claw device 20 a, and is provided between the two claw devices 20 a to rotate. Air is discharged radially outward from the shaft. The claw holding member 20b has a substantially rectangular cross section connecting the two claw devices 20a, and the claw holding member 20b is provided inside the transfer cylinder rotation locus 25 except for the two claw device 20a portions. Further, the in-cylinder air discharge device 21 is also provided inside the transfer cylinder rotation locus 25.

  The transfer drum upper air suction device 22 includes a guide plate (hereinafter referred to as a transfer drum upper suction guide) 22a and a plurality (three in FIG. 2) of suction fans 22b. The transfer drum upper suction guide 22a is a hollow plate-like member provided above the transfer drum 20 along the transfer drum rotation track 25 so as to have a predetermined gap with the transfer drum rotation track 25. A number of holes are formed over the entire surface of the transfer cylinder 20 side. The suction fan 22b is disposed along the circumferential direction on the surface opposite to the transfer drum 20 of the transfer drum upper suction guide 22a, and through a hole of the transfer drum upper suction guide 22a provided in the arrangement portion. Air is sucked from the transfer cylinder 20 side toward the radially outer side.

  The transfer upper air discharge device 23 includes a DC blower 23a and two transfer upper air discharge members 23b connected to the DC blower 23a via a pipe 23c. The transfer cylinder upper air discharge member 23b is disposed above and opposite the axial end of the sheet transfer position from the impression cylinder 10 to the transfer cylinder 20 (contact point with the transfer cylinder rotation locus 25 of the impression cylinder 10). The axial direction center side of the transfer cylinder 20 is fixed to the frame 4 supporting the transfer cylinder 20 so that the sheet 5 conveyed on the upper part of the transfer cylinder 20 is conveyed along the transfer cylinder upper suction guide 22a. And air is discharged upward. That is, the sheet 5 is blown up toward the transfer upper suction guide 22a.

  The transfer drum lower air discharge device 24 includes a DC blower 24a and a transfer drum lower air discharge member 24b connected to the DC blower 24a via a pipe 24c. The transfer drum lower air discharge members 24 b are fixed to the frame 4, provided in two rows along the circumferential direction of the transfer drum rotation locus 25 below the transfer drum 20, and a plurality (see FIG. In order to prevent the sheet 5 being conveyed by the transfer cylinder 20 from coming into contact with the transfer cylinder 20, respectively, upward and in a direction substantially parallel to the peripheral surface of the transfer cylinder 20, That is, air is discharged between the transfer cylinder 20 and the sheet 5.

  In this embodiment, the impression cylinder 10 is provided with an impression cylinder lower air discharge device 15. The impression cylinder lower air discharge device 15 includes a guide plate (hereinafter referred to as an impression cylinder lower air guide) 15a and a plurality (two in FIG. 2) of discharge fans 15b. The impression cylinder lower air guide 15a is in the vicinity of the sheet delivery position and upstream of the delivery position, in other words, on the circumferential surface of the impression cylinder 10 below the impression cylinder 10 and on the delivery position side. A cylinder circumferential surface of the impression cylinder is a hollow plate-like member provided with a predetermined gap, and a large number of holes are formed on the entire surface of the impression cylinder 10 side. The suction fan 15b is arranged along the circumferential direction on the surface of the impression cylinder lower air guide 15a opposite to the impression cylinder 10, and is pressurized through a hole in the impression cylinder lower air guide 15b provided in the arrangement portion. Air is discharged toward the barrel 10 side.

  The sheet 5 offset-printed by the printing unit 2 described above is transferred from the impression cylinder 10 of the printing unit 2d for the fourth color to the discharge cylinder (transfer cylinder) 30, and is sequentially conveyed by the discharge chain 31 to be It is selectively discharged onto the stage piles 32a, 32b.

  In this embodiment, the printing units 2a to 2d constitute printing means, the cylinder air discharge device 21 forms cylinder air discharge means, and the transfer cylinder upper air suction device 22 sets transfer cylinder upper air suction means. The transfer cylinder upper air discharge device 23 constitutes the transfer drum upper air discharge device, the transfer drum lower air discharge device 24 forms the transfer drum lower air discharge device, and the impression cylinder lower air discharge device 15 forms the lower pressure drum lower portion. It constitutes an air discharge means.

  According to the sheet-fed printing press according to the present embodiment configured as described above, the sheet 5 conveyed between the adjacent printing units 2a to 2d is transferred from the impression cylinder 10 on the upstream side in the sheet conveyance direction to the transfer cylinder 20. When the sheet 5 is transferred to the transfer cylinder 20, the sheet 5 is first transferred between the impression cylinder 10 and the impression cylinder lower air guide 15b of the impression cylinder lower air discharge device 15 to the transfer cylinder 20. At this time, the sheet 5 moves on the circumferential surface of the impression cylinder 10 in a state in which air is blown from the lower drum air discharge device 15 toward the circumferential surface of the impression cylinder 10 and fluttering is suppressed.

  When the sheet 5 is transferred from the impression cylinder 10 to the transfer cylinder 20, air is blown to the sheet 5 from the cylinder air discharge device 21 toward the outer side in the radial direction with respect to the rotation shaft of the transfer cylinder 20. Air is sucked through the hole of the transfer upper suction guide 22a by the suction fan 22b of the transfer upper air suction device 22, and the sheet 5 is placed on the inner peripheral surface of the transfer upper suction guide 22a from the peripheral surface of the impression cylinder 10. It moves with the fluttering being suppressed along.

  At this time, air is further blown onto the sheet 5 from the transfer drum lower air discharge device 24 upward and in a direction substantially parallel to the peripheral surface of the transfer drum 20, and from the transfer drum upper air discharge device 23. Air is blown toward the upper side in the axial direction of the cylinder 20 and upward, whereby the behavior of the sheet 5 becomes more stable.

  As described above, according to this embodiment, in the printing machine that includes the ink unit 12 below the impression cylinder 10 and performs printing on the lower surface of the sheet 5 that is conveyed below the impression cylinder 10, the flapping of the sheet 5 occurs. It is possible to convey the sheet 5 with a stable behavior while suppressing the occurrence of scratches, rubbing and the like on the printing surface of the sheet 5.

[Other Examples]
In the embodiment described above, a sheet-fed printing machine that performs printing on one side of the sheet 5 includes a cylinder air discharge device 21, a transfer cylinder upper air suction device 22, a transfer cylinder upper air discharge device 23, a transfer cylinder lower air discharge device 24, Although the example in which the pressure drum lower air discharge device 15 is provided has been described, the present invention is not limited to the above-described embodiment, and may be applied to a sheet-fed printing machine that performs printing on both sides of a sheet.

  As a sheet-fed printing machine that performs printing on both sides of a sheet, for example, printing is performed on one side of the sheet with the printing units 2a and 2b in FIG. 1, and printing is performed on the other side of the sheet with the printing units 2c and 2d. Can be considered. In this case, in the printing units 2c and 2d, an impression cylinder is provided at the position of the transfer cylinder 20 shown in FIG. 1, and the transfer cylinder is provided between the impression cylinders of the printing units 2c and 2d. Further, in these printing units 2c and 2d, the ink unit, the plate cylinder, and the rubber cylinder are disposed above the impression cylinder.

  The sheet is transferred from the impression cylinder of the printing unit 2b to the impression cylinder of the printing unit 2c, and printing is performed on the other surface by the ink unit, the plate cylinder, and the rubber cylinder provided above the impression cylinder in the printing unit 2c. After that, it is transferred to the impression cylinder of the printing unit 2d through the transfer cylinder, and further printing is performed on the other surface by the ink unit, plate cylinder, and rubber cylinder provided above the impression cylinder in the printing unit 2d. After that, it is delivered to the paper discharge cylinder 30 and discharged.

  In the sheet-fed printing machine configured as described above, in particular, the impression cylinder lower air discharge device 15 is provided in the impression cylinder of the printing unit 2a, and the cylinder air discharge device 21 is provided in the transfer cylinder provided between the printing units 2a and 2b. By providing the transfer drum upper air suction device 22, the transfer drum upper air discharge device 23, and the transfer drum lower air discharge device 24, it is possible to obtain the same functions and effects as the above-described embodiment, which is preferable.

  INDUSTRIAL APPLICABILITY The present invention is suitable for application to a printing machine having a printing unit in which a plate cylinder and an ink unit are provided below the impression cylinder and printing is performed on a sheet conveyed on the cylinder circumferential surface of the impression cylinder. is there.

DESCRIPTION OF SYMBOLS 1 Sheet supply part 2 Printing part 2a-2d Printing unit 3 Sheet discharge part 4 Frame 5 Sheet 6a, 6b Stacking board 7 Feeder board 8 Swing apparatus 9 Paper feed cylinder 10 Impression cylinder 11 Plate cylinder 12 Ink unit 13 Ink fountain apparatus 14 Roller group DESCRIPTION OF SYMBOLS 15 Pressure drum lower air discharge device 15a Pressure drum lower air guide 15b Discharge fan 16 Rubber drum 20 Transfer drum 20a Claw device 20b Claw holding member 21 Body air discharge device 22 Transfer drum upper air suction device 22a Transfer drum upper suction guide 22b Suction Fan 23 Transfer cylinder upper air discharge device 23a DC blower 23b Transfer drum upper air discharge member 23c piping 24 Transfer drum lower air discharge device 24a DC blower 24b Transfer drum lower air discharge member 24c piping 25 Transfer cylinder rotation trajectory 30 Paper discharge drum 31 Discharge Paper chain 32a, 32b Le

Claims (3)

A printing means for holding the leading end side of the sheet in the conveyance direction and conveying the sheet below the cylinder circumferential surface to print the sheet; and a leading end side in the conveyance direction of the sheet that receives the sheet from the impression cylinder In a sheet-fed printing press equipped with a transfer cylinder that holds a sheet and conveys a sheet on the upper side of the cylinder,
The transfer drum is a skeleton-type drum,
An in-cylinder air discharge means for discharging air toward the radially outer side with respect to the rotation axis of the transfer cylinder, which is provided at the core of the transfer cylinder ;
Air is discharged toward the printed sheet provided opposite to the sheet conveying surface of the impression cylinder on the lower side of the impression cylinder and on the side of the sheet transfer position from the impression cylinder to the transfer cylinder. A pressure drum lower air discharge means;
A sheet-fed printing press, comprising: a transfer cylinder upper air suction unit provided on the upper side of the transfer cylinder so as to face a trajectory associated with the rotation of the transfer cylinder and sucking air . Air is discharged toward the sheet conveyed by the transfer cylinder from both sides in the rotation axis direction of the transfer cylinder and from the inside in the radial direction with respect to the rotation axis, above the sheet transfer position from the impression cylinder to the transfer cylinder. sheet-fed printing press according to claim 1, further comprising a transfer cylinder upper air discharge means. The sheet-fed printing press according to claim 1 or 2, further comprising: a transfer cylinder lower air discharge unit configured to discharge air from below the transfer cylinder toward the transfer cylinder and the sheet.

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