JP6468685B2 - Sheet-fed printing machine - Google Patents

Description

  The present invention relates to a sheet-fed printing press provided with a sheet discharge table for stacking and holding printed sheets, and more particularly to a sheet-fed printing press provided with a guide member for guiding passage of sheets.

  In a printing machine, when a printed sheet is conveyed to a paper discharge unit, a guide member (guide member) is provided above the paper discharge table so as to be able to appear and retract, and an air cylinder that drives the guide member is operated to perform a guide. There is a technique for advancing the members and guiding the conveyed sheet to prevent the sheet from being damaged and to improve the printing quality. Patent Document 1 discloses such a sheet-fed printing press.

JP 2010-47338 A

  By the way, when the guide member advances, there is a possibility that the advancing guide member may come into contact with the sheet to be transported and discharged to impair the quality of the sheet. Further, the advancement of the guide member may not catch up with the sheet that is transported and dropped. According to the technique of Patent Document 1, although there is a disclosure of a technique for suppressing the impact force of the guide member and improving the durability of the guide member retracting mechanism, there is no description regarding the problem at the time of advancement of the guide member, and there is room for improvement. was there.

  The present invention was made to solve such a problem, and an object of the present invention is to provide a sheet-fed printing machine that can prevent the sheet from being damaged when the guide member advances and can improve the printing quality. To do.

In order to achieve the above object, the present invention is provided with a printing unit B and a paper discharge unit C having a paper discharge table 21 on which the sheet S printed and conveyed by the printing unit B is discharged. In the sheet printing machine in which guide members 310 and 320 for guiding the sheet S are provided so as to be able to advance and retract above the sheet discharge table 21, the guide members 310 and 320 are arranged in the transport direction with the sheet discharge table 21 interposed therebetween. At least one pair is provided on the upstream side and the downstream side of the paper, and the advance speed of the upstream guide member 310 is equal to or faster than the transport speed of the sheet S when being transported above the paper discharge table 21. It is characterized by being controlled as follows.

Further, the advance speed of the upstream guide member 310 is controlled so as to follow the change in the transport speed of the sheet S when being transported above the paper discharge table 21 .

  The advance speed of the downstream guide member 320 is controlled to be faster than the advance speed of the upstream guide member 310.

  In the sheet-fed printing press of the present invention, it is possible to improve the printing quality in the printing press having the guide member on the paper discharge table.

1 is a schematic cross-sectional side view of a sheet-fed printing press according to the present invention. FIG. 6 is an enlarged side view of a paper discharge unit. FIG. 4 is an enlarged plan view of a paper discharge unit, showing a state where a guide member is retracted. FIG. 4 is an enlarged plan view of a paper discharge unit, showing a state where a guide member has advanced. It is a block diagram which shows a control part.

  Hereinafter, a sheet-fed printing press according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. 1 is an example of a sheet-fed printing machine provided with a guide member for a paper discharge unit according to the present invention. As shown in FIG. 1, the sheet-fed printing press according to this embodiment is a sheet-fed offset sheet-fed printing press. The sheet-fed printing machine includes a sheet feeding unit A for feeding out sheets S as printing sheets one by one from a sheet stacking unit by a feeder device, a sheet separating device, and the like, and a sheet from the sheet feeding unit A A printing unit B for printing on S and a paper discharge unit C for discharging the sheet S are provided. Here, the printing unit B is a printing unit B including four printing units 5 so that four colors can be printed. However, the printing unit can print colors other than four colors, that is, one color or two or more colors. It may be. The specific configuration of each part constituting the printing press is not limited to that shown in the figure. The printing machine is driven by a machine motor M (not shown).

  The printing unit 5 of the printing unit B includes a plate cylinder 1, a rubber cylinder 2, an ink roller group (not shown) as an ink supply unit, an impression cylinder 3, and a transfer cylinder 6. Although not shown, the plate cylinder 1 is provided with a pair of plate clamps for fixing the plate wound around the peripheral surface thereof. A blanket (not shown) is wound around the rubber cylinder 2. Each of the impression cylinders 3 is provided with grippers (not shown) for gripping the fed sheet S with the nail base and the claws at two locations in the circumferential direction (one or three or more locations). ing. Reference numeral 7 denotes a paper feed cylinder, which receives a sheet S, which is transported on the feeder board 8 and positioned in the transport direction (in the direction of arrow Z in FIG. 1) by a front contact (not shown), from a swing arm (not shown). Plays the role of passing to 3. The feeding cylinder 7 and the swing arm are also provided with the claw base and the claw.

  As shown in FIGS. 1 and 2, the paper discharge unit C is configured by a chain transport device. That is, an endless discharge chain 13 is wound around a sprocket 11 provided on the upstream side in the conveyance direction of the sheet S and a sprocket 12 provided on the downstream side in the conveyance direction adjacent to the impression cylinder 3 of the final printing unit 5. The paper discharge chain 13 rotates around the sprockets 11 and 12 while being restricted by a chain guide (not shown). The paper discharge chain 13 is provided with a chain gripper 14 having the same structure as the above-described claw base and claw, and can transport the sheet S.

  In the paper discharge unit C, two paper discharge trays 21 and 22 are provided. The two paper discharge trays 21 and 22 are inspected by a print quality inspection device (not shown) provided in the printing unit, and the normal paper with good printing and the damaged paper with poor printing are discharged separately. This is used for discharging the printed sheet S to two discharge trays when printing more than the number that can be accommodated on one discharge tray.

  As shown in FIGS. 2 to 4, the guide member according to the present invention is located above one of the paper discharge trays 21 and on the upstream side and the downstream side in the transport direction (arrow Z direction) with the paper discharge tray 21 interposed therebetween. 310 and 320 are provided. The guide members 310 and 320 are located below the guide plates 50 and 50 provided between the frames F and F on the left and right sides (direction orthogonal to the transport direction) of the paper discharge unit C.

  The upstream guide member 310 includes an air cylinder 311 and a guide plate 312 fixed to the rod of the air cylinder 311 and capable of moving forward and backward in the transport direction (Z direction) from below the guide plate 50. Similarly, the downstream guide member 320 includes an air cylinder 321 and a guide plate 322 that is fixed to the rod of the air cylinder 321 and can be advanced and retracted from below the guide plate 50 in the transport direction (Z direction). As with the guide plate 50, the guide plate 312 is formed as a smooth flat surface so that it will not be damaged even if the sheet S comes into contact therewith. Reference numeral 51 denotes a known sheet brake arranged substantially flush with the guide plate 50. The sheet brake S abuts against the rear end of the sheet S while rotating and sucking, thereby reducing the conveyance speed of the sheet S. Let

  FIG. 5 is a schematic block diagram illustrating the configuration of the control unit 80 according to the present invention. The control unit 80 includes the paper feeding unit A, the printing unit B, the paper discharge unit C, the motor motor M, and the guide. Members 310 and 320 are connected. The control unit 80 includes a microprocessor 81 (may be a sequencer) that performs arithmetic processing, a ROM 82 that stores data and a predetermined program (such as an arithmetic expression or a table), and a RAM 83 that can store various types of information related to the number of rotations of the machine. And an interface 84 that mediates the exchange of various signals between the microprocessor 81 and a device (all not shown) provided outside the control unit 80.

  The operation of the present invention will be described. When the paper discharge table 21 is used, the guide plates 312 and 322 of the guide members 310 and 320 are in the retracted positions as shown by the solid lines in FIG. 2 and FIG. 3, and the sheet S is discharged onto the paper discharge table 21. . The sheet S is conveyed and discharged without being damaged while being in contact with the guide plate 50.

  When the paper discharge table 21 is not used (when the paper discharge table 22 is used), the guide plates 312 and 322 of the guide members 310 and 320 advance to the advanced position as shown by the dotted lines in FIG. 2 and FIG. At this time, the control unit 80 adjusts the amount of air supplied to the air cylinder 311 so that the upstream guide plate 312 is the same speed as or slower than the conveyance speed of the sheet S. By controlling in this way, the upstream guide plate 312 does not press the conveyed sheet S when it advances, and the sheet S is not damaged, and the print quality is improved. I can do it.

  Further, the advance speed of the upstream guide plate 312 is controlled so as to follow the change in the transport speed of the sheet S, that is, the speed of the printing press. By controlling in this way, the advancing speed of the guide plate 312 can always be the same as or slower than the conveying speed of the sheet S, and the print quality can be reliably improved.

  The advance speed of the downstream guide plate 322 is controlled faster than the advance speed of the upstream guide plate 312. By controlling in this way, the advancement of the guide plate 322 is not in time for the fall of the sheet S to be transported and discharged, and transport troubles can be reliably prevented.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention. For example, in the above-described embodiment, the guide members 310 and 320 are provided only on the one paper discharge tray 21, but the guide members may be provided on the other paper discharge tray 22. Further, although two paper discharge tables are provided, the present invention can be applied to a printing machine having one paper discharge table.

  In the above-described embodiment, the offset sheet-fed printing machine is used. However, the present invention is not limited to this, and other types of sheet-fed printing machines may be used as long as the sheet-fed printing machine has a guide member on the paper discharge tray. Good.

  The sheet-fed printing press according to the present invention is extremely useful in a sheet-fed printing press having a guide member on a sheet discharge table.

1: Plate cylinder 2: Rubber cylinder 3: Impression cylinder 5: Printing unit 6: Transfer cylinder 7: Paper feed cylinder 8: Feeder board 11: Sprocket 12: Sprocket 13: Paper discharge chain 14: Chain gripper 21: Paper discharge tray 22 : Discharge tray 50: guide plate 80: control unit 81: microprocessor 82: ROM
83: RAM
84: interface 310: guide member 311: air cylinder 312: guide plate 320: guide member 321: air cylinder 322: guide plate A: paper feed unit B: printing unit C: paper output unit F: frame M: machine motor S : Sheet Z: Arrow

Claims (3)

A printing unit and a paper discharge unit having a paper discharge table for discharging the sheet printed and conveyed by the printing unit are provided, and a guide for guiding the sheet is provided above the paper discharge table. In a sheet-fed printing machine in which members are provided so as to freely advance and retract,
At least a pair of the guide members are provided on the upstream side and the downstream side in the transport direction with the paper discharge table interposed therebetween, and the advance speed of the guide member on the upstream side is a sheet when the paper is transported above the paper discharge table. A sheet-fed printing press controlled at the same speed or lower than the paper transport speed. 2. The sheet printing according to claim 1, wherein the advance speed of the upstream guide member is controlled so as to follow a change in a sheet conveying speed when being conveyed above the sheet discharge table. Machine. 3. The sheet-fed printing press according to claim 1, wherein the advance speed of the downstream guide member is controlled to be faster than the advance speed of the upstream guide member.

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