JP2008308321A - Paper delivery device for paper sheet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper delivery device for a paper sheet printer in which a problem of the flapping of a paper sheet in paper delivery is solved, problems of a flaw and a smudge on the printing surface of the paper sheet and the folding of the paper sheet are prevented, and the delivery and receipt of the paper sheet from a printing part can be performed without a trouble. <P>SOLUTION: A straightening cover 10 is disposed at a front surface in the traveling direction of a chain gripper 2 of the delivery device 1. The straightening cover 10 has a curved cross section which is projected in a traveling direction to separate air in front of the chain gripper into an upward flow and a downward flow and makes the air flow backward. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a paper discharge device in a sheet-fed printing press, and more particularly to a paper discharge device in a sheet-fed printing press that stably discharges and stacks sheets by preventing flapping during conveyance of printed sheets. .

  A conventional sheet-fed printer has a structure in which a sheet that has been printed by a printing unit is transported to a predetermined position by a chain gripper that is continuously connected to a rotating endless chain. It has become. However, in recent years, with the improvement in printing speed, it has become difficult to stack sheets uniformly on a paper discharge table by performing good paper alignment. In order to solve this problem, it is equipped with a suction device that sucks the trailing edge of the conveyed sheet and applies a brake, and moves at the same speed as the sheet to support the sheet and constantly rotates. When a chain gripper releases the paper, the conveyance speed of the sheet is reduced, and the sheet is applied to the paper pad and aligned on the paper discharge tray. Like to do.

  By the way, in such a configuration, an air flow enters between the running sheet and the conveyance table or the conveyance belt, and the printed sheet flutters and comes into contact with a paper guide or the like. There are problems such as scratches and dirt on the paper, and folding of the sheet. This phenomenon becomes more prominent as the sheet conveyance speed increases as the printing speed increases, and this is an obstacle to increasing the printing speed.

  In order to solve this problem, a shielding plate is provided in front of the chain gripper shaft so as not to create a gap between the chain gripper and the lower paper guide, thereby preventing air from entering and preventing flapping of the sheet. An example of related technology has been reported (see Patent Document 1).

Japanese Patent Laid-Open No. 7-267552

  However, in this example, flapping of the sheet is not completely eliminated because air is trapped from above the chain gripper shaft. In addition, due to its structure, there is a problem in that it easily interferes with surrounding members when a sheet is transferred between the impression cylinder, the discharge cylinder, and the chain gripper, and there is a problem that the sheet cannot be easily transferred.

  The present invention has been made in view of the above circumstances, and eliminates the flapping of the sheet at the time of paper discharge, causing the printed surface of the sheet to be scratched or stained, or to bend the sheet. It is an object of the present invention to provide a sheet discharge device for a sheet-fed printing machine that can prevent the troubles that occur and can deliver a sheet from a printing unit without any trouble.

In order to solve the above-described problems, the present invention provides a sheet discharge device for a sheet-fed printing machine for holding a sheet that has been printed by a printing unit by a chain gripper, transporting it onto a sheet discharge table, and stacking it. A rectifying cover is provided on the front side of the chain gripper in the running direction so that air on the front side of the chain gripper is divided into upper and lower parts and flows backward.
Accordingly, it is possible to realize a sheet discharge device for a sheet-fed printing machine that can prevent the sheet from flapping due to an air flow directly against the sheet being conveyed.

Here, the chain gripper includes a plurality of claw portions on a claw shaft supported at both ends by an endless chain, and the rectifying cover has a front surface of the chain gripper positioned at both ends of the plurality of claw portions. The height from the lower end of the rectifying cover occupied by the apex of the convex curved surface of the cross section while the chain gripper is transporting the sheet is Is lower than half of the height from the lower end occupied by the upper surface of the rectifying cover in the plane perpendicular to the traveling direction of the chain gripper passing through the cross-sectional center of the claw shaft, and the amount of air flowing upward from the apex thereof is More than the amount of air flowing downward.
As a result, the air in front of the chain gripper is mainly flowed to the upper rear side of the rectifying cover, and the amount of air flowing below the rectifying cover is made smaller than the upper side to prevent the sheets from flapping during conveyance.

Further, the rectifying cover has a top surface longer than a bottom surface in the running direction.
Thus, the air flow can be made to flow upward behind the rectifying cover, and the lower surface of the rectifying cover can be prevented from interfering with the operation when the sheet is transferred from the printing unit to the chain gripper.

Further, the rectifying cover maintains a position that is not more than a predetermined distance away from the cylinder of the printing unit when the sheet is changed from the printing unit to the chain gripper. To do.
This avoids a situation where the rectifying cover, especially the lower end of the rectifying cover, touches the cylinder or the sheet of the printing unit when delivering the printed sheet, and hinders the normal delivery of the sheet, Stable paper discharge can be performed.

  Since the present invention is configured and functions as described above, it prevents the sheet from being fluttered by direct air flow against the sheet being conveyed at the time of paper discharge, and the printed surface of the sheet is not damaged. It is possible to provide a sheet discharge device for a sheet-fed printing press that can prevent the occurrence of stains or breakage of the sheet, and can transfer the sheet from the printing unit without any trouble. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a side view for explaining a sheet discharge device of a sheet-fed printing machine in which the present invention is used.

  The sheet 6 for which predetermined printing has been completed is delivered from the printing cylinder 18 at the final stage of the printing apparatus to the paper discharge apparatus 1. That is, the sheet 6 is transferred to the chain gripper 2 of the paper discharge device 1 provided in the endless chain 9 that travels by winding the sprocket 19, and is held on the conveyor belt 11 while being held by the chain gripper 2. Be transported.

  Then, the sheet 6 is sucked by the vacuum suction wheel 8 downstream of the conveying belt 11 and the speed of the sheet 6 is braked, and the sheet 6 falls to the discharge table 20 in a decelerated state, and is located on the downstream side of the sheet stacking unit. The front end is aligned with the front abutting provided on the paper holder, released from the chain gripper 10 at an appropriate position, and sequentially dropped onto the pallet of the paper discharge tray 20 and stacked.

  By the way, with the recent increase in the printing speed, the conveyance speed of the sheet 6 in the paper discharge device 1 is also increased, and thereby, the high speed air between the running sheet 6 and the conveyance belt 11. There is a problem that the flow invades and the sheet 6 flutters. In order to solve this problem, in the present invention, the rectifying cover 10 is provided on the front surface of the chain gripper 2 so that the air flow directly hits the sheet 6 and does not flutter the sheet 6.

FIG. 2 shows a bottom view of the chain gripper 2, and FIG. 3 shows a sectional side view thereof.
The chain gripper 2 has a plurality of claw portions each having a claw shaft 3 supported at both ends by an endless chain 9 and a claw base 5 and a gripping claw 4 provided on the claw shaft 3. The sheet paper 6 is picked up and conveyed by the gripping claws 4.

  In FIG. 2, the front of the chain gripper 2 in the traveling direction, which is the direction from the bottom to the top (the direction of the arrow A) in FIG. 2, and the direction from the right to the left (the direction of the arrow A) in FIG. 10 is provided so as to cover all the claws, including those at both ends thereof, and the air flow from the front directly hits the chain gripper 2, and the sheet 6 gripped by the chain gripper 2 flutters. Is prevented.

  As shown in FIG. 3, the rectifying cover 10 has a curved surface whose cross section is convex with respect to the traveling direction. This curved surface plays a role of dividing the air flow coming from the front surface of the chain gripper 2 in the traveling direction at the apex of the convex portion (indicated by P in FIG. 3) and flowing it backward. At this time, the air in front of the chain gripper 2 is mainly flowed to the upper rear by adjusting the ratio of the height of the upper part from the vertex (P) of the rectifying cover 10 and the height of the lower part from the vertex (P). The amount of air flowing in the lower side is made smaller than the amount of air flowing in the upper side, and the amount is always constant.

  Specifically, when the chain gripper 2 travels while transporting the sheet 6, the height from the lower end (indicated by E in FIG. 3) of the apex (P) of the convex curved surface of the cross section thereof. (Indicated by h in FIG. 3) is the height from the lower end (E) occupied by the upper surface of the rectifying cover 10 in a plane that passes through the center of the cross section of the claw shaft 3 and is perpendicular to the traveling direction of the chain gripper 2 (H in FIG. 3). It was made to be lower than half of (shown in). As a result, the amount of air flowing to the upper rear can be made larger than the amount of air flowing to the lower rear.

  As described above, since the amount of air flowing on the upper surface side of the rectifying cover 10 is increased and the amount of air flowing on the lower surface side is decreased, the air flow flowing on the sheet 6 side can be decreased, and the sheet 6 flutters. Can be prevented. In addition, the length of the lower surface is shorter than the length of the upper surface of the rectifying cover 10 so that the lower surface of the rectifying cover does not interfere with the operation when the sheet is transferred from the printing unit to the chain gripper. Even if it does, the trouble to the function which prevents the air flow of the rectification | straightening cover 10 will decrease.

  When the rectifying cover 10 as described above is used, a negative pressure portion where an air flow does not flow directly behind the rectifying cover 10 is generated. Since the sheet 6 is transported in the negative pressure portion, it can be stably transported without flapping. Further, the rectifying cover 10 has a smooth surface so as not to generate vortices or the like so as to prevent air turbulence around the chain gripper 2.

FIG. 4 is an explanatory diagram showing the states of the peripheral parts immediately before the sheet 6 is changed over from the printing cylinder 18 of the printing unit to the chain gripper 2 of the paper discharge device 1.
The tail change is performed on a line connecting the center of the sprocket 19 that rotates the endless chain 9 to which the chain gripper 2 is attached and the center of the printing cylinder 18 of the printing unit.

  As described above, the rectifying cover 10 has a lower surface shorter than the upper surface and does not extend to the position where the gripping claws 4 hold the sheet 6. It does not affect the change. Further, since the lower end (E) of the rectifying cover 10 is configured to maintain a predetermined distance from the printing cylinder 18, the rectifying cover 10 and the printing cylinder 18 do not interfere with each other, and printing is performed by interference. There will be no trouble in paper discharge.

  As described above, the air flow generated by the movement of the chain gripper 2 is flowed to the rear upper part or rear lower part of the claw shaft 3 by the rectifying cover 10 and is fed to the gripping claws 4 of the chain gripper 2. Since turbulence does not act on the sheet 6, the sheet 6 does not flutter, and the sheet 6 can be stably conveyed.

  The present invention can prevent fluttering of a sheet being conveyed in a sheet discharge device of a sheet-fed printing press, and thus can be widely used in a wide field in the manufacturing and printing industries of a sheet-fed printing press. Have.

It is a side view for explanation of a paper discharge device of a sheet-fed printing machine in which the present invention is used. It is a bottom view of the chain gripper used for the paper discharge device of the present invention. It is a cross-sectional side view of a chain gripper used in the paper discharge device of the present invention. It is explanatory drawing which shows the state of each peripheral part immediately before changing a sheet from the impression cylinder of a printing part to the paper discharge apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Conveying device 2 Chain gripper 3 Claw shaft 4 Claw claw 5 Claw base 6 Sheet paper 8 Vacuum suction wheel 9 Endless chain 10 Rectification cover 11 Conveying belt 18 Printing cylinder 19 Sprocket 20 Discharge stand

Claims (4)

In the sheet discharge device of the sheet-fed printing machine, the sheet that has been printed in the printing unit is picked up by a chain gripper, transported onto a sheet discharge table, and dropped and stacked.
A sheet discharge device for a sheet-fed printing machine, wherein a rectifying cover is provided on the front side of the chain gripper in the running direction so as to divide the air on the front side of the chain gripper up and down and flow backward. The chain gripper includes a plurality of claw portions on a claw shaft supported at both ends by an endless chain, and the rectifying cover includes one in which a front surface of the chain gripper is positioned at both ends of the plurality of claw portions. Having a cross section with a curved surface that covers and convex in the running direction;
While the chain gripper is transporting the sheet, the height from the lower end of the straightening cover occupied by the apex of the convex curved surface of the cross section passes through the center of the cross section of the claw shaft and is perpendicular to the traveling direction of the chain gripper. The amount of air that flows below the top of the rectifying cover on a flat surface that is lower than half of the height from the lower end and that flows above its apex is greater than the amount of air that flows downward. The paper discharge device for the sheet-fed printing press described.   3. The sheet discharge device for a sheet-fed printing press according to claim 1, wherein the rectifying cover has an upper surface longer than a lower surface in the running direction.   The rectifying cover maintains a position that is not more than a predetermined distance away from a cylinder of the printing unit when the sheet is changed from the printing unit to the chain gripper. The sheet discharge device for a sheet-fed printing press according to any one of claims 1 to 3.

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