JPS5817059A - Method and apparatus for straightening sheet of paper - Google Patents

Abstract

PURPOSE:To automatically straighten sheets of paper and save labor, by providing an inverter which inverts the sheet of paper while bending it into a U- shape on a table, and a presser which presses the bent part of the sheet on the table. CONSTITUTION:The sheet A of paper is placed on a feed belt on the table 1, and an end part of the sheet A is clamped by a jaw part 9 of a curved guide part 4 in the inverter 2. After clamping the sheet A by the jaw part 9, the belt is stopped, from which condition the sheet A is automatically bent into a circular form, then it is transferred to a jaw part 18 of a rectilinear guide part 5, and turning back is further advanced. Whle advancing the turning back, the bent part B of the sheet A is sequentially pressed by the presser 3, thereby straightening the sheet A or forming a fold line in the direction orthoronal to the feed direction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for correcting various paper curls occurring in printing sheets and reliably suspending them from the feeder of a single-fed printing press to the printing section.

In general, sheet-fed printed matter, especially sheets of paper that have been left alone after printing on one side, have a variety of paper curls.

If a sheet of paper with this paper curl has been printed on its entire surface, it is extremely difficult to smoothly remove it from the feeder of the printing press.

For this reason, conventionally, when printing is to be performed again, an operator folds the sheet to make a crease, removes the paper curls, and then supplies the sheet to the printing machine.

Also, paper with a small weight (f/w?) has no rigidity, so
If it does not come out of the feeder, or even if it does come out, it will simply bend down when it hits the marking machine, and the gripper will not be able to bite it accurately, resulting in misalignment of the printed teeth.

For this reason, for non-rigid paper, before printing and after single-sided printing, the operator can increase the rigidity by folding the printing paper, folding it back, and making creases in the same way as when removing curls. It is then supplied to the printing press.

The present invention is based on the conventional situation such as the above, and the present invention is based on a method and apparatus for automatically straightening and straightening sheets in order to reduce the time-consuming and labor-intensive work of removing curls and making creases. All that is offered.

The present invention will be explained below with reference to embodiments shown in the drawings.

In Figures 1 to 3, a conveyor belt Ot- on which a required number of stacked sheets is placed is shown.
The table 1 with which the sheet is folded, the reversing device 2 that inverts the sheet while folding it into the shape of an Iff on the table 1, and the bending of the sheet folded by the reversing device 2 wB It is equipped with a pressure device 3 that presses the pressure on the meeting table l from above.

The above-mentioned reversing device 2 includes a bending guide s4 that grasps the leading end of a two-sheet sheet and rolls it backwards, and a bending guide s4 that takes the leading end tube holder of a sheet of paper from the bending guide @j and folds it back again. Matoi guide l
It consists of is.

Curved guide portion 4, as shown in Figures 84-5.

An endless chain 81 is built into the sprocket 6 and the support roller 7, and a jaw fl 19 is attached to the end of the sheet. The jaw part 9 has an upper @1G having a constant angle and a lower jaw 11 that can be opened and closed.
1 is biased in the closing direction by a spring 12. Further, the lower I[11 is provided with an opening/closing lever 13, and its bearing 14 engages with a cam 15, 16, thereby opening and closing the opening/closing lever.

Also, K as well as the linear guide l554 of the reversing device 2.

As shown in No. 6, an endless chain 17, a jaw 18 attached to the chain, a cam 19, 20, and a limit switch 21 for limiting the amount of movement of the jaw 1B are provided. ing.

On the other hand, the pressing device 3 has a large number of pressing plates 3 a * 3 b e 3 c * arranged in a row to press one side of the folded sheet of paper. ”・”・<
Has these suppressor air or hydraulic cylinders 22
It is moved up and down by. Each press plate 0 press timing is determined by a large number of detectors 8 using phototubes such as a light emitter 23 and a light receiver 24.
It is detected by 1*86+Elm, -...-. For example, when the detector 81 detects passage of a bent portion B of a sheet, the suppression plate 3a is activated. Also, when each suppression plate 3a tatami presses.

The operation of the straight guide 5 in the reversing device 2 is temporarily stopped, and the movement of the jaw is temporarily stopped.

As is clear from the structure of the above embodiment, when performing paper curling or folding work using this device, the operator places the conveyor belt OK on the paper cutting table 1, and then -1 By driving the motor, the leading end of the sheet of paper is made to bite into the guide jaws 11 of the reversing device 2. After the jaws 9 are engaged, the transport bell) O has stopped. From this state, the sheet of paper is automatically rolled up as shown in FIG. 3, and then passed over the jaw 1BK of the linear guide BS and further folded.

While the folding is progressing by the jaw part 1BK, the bending of one sheet of paper is sequentially pressed by the pressurizing device 3, and the folding work is performed in a direction perpendicular to the bending direction and the horizontal feeding direction. or is done.

Figure 7 shows a folded sheet of paper.
When printing a sheet of paper, the crease 26 at the bite part @ 25 is the press plate aa
13'blac... is tightly formed.

As described above, according to the present invention, the work of deforming or folding sheets of paper, which was conventionally done manually, is automatically performed, and the labor of the operator can be reduced. At the same time, there is an advantage that even the kinks of one sheet of paper can be removed more reliably.

Moreover, it can completely remove paper curls, ensuring that each sheet of paper comes out of the printer's feeder reliably.

The gripper can be gripped accurately9, printing misregistration can be prevented from occurring, and therefore printing interference time can be shortened.

This can bring about an extremely large effect on print quality.

[Brief explanation of drawings]

Fig. 1 is an overall perspective view of a correction device according to an embodiment of the present invention, Fig. 2 is a plan view of the main part of Fig. 1, Fig. 3 is a front view of Fig. 1, and Figs. 4 to 6 fa6. FIG. 7 is a detailed explanatory view of the reversing device in the straightening device VC shown in FIG. 1, and FIG. 7 is a plan view of a folded sheet. 1--table, 2--reversing device, 3--pressing device, 26--fold, A-- sheet of paper.

Claims (2)

[Claims] (1) Correcting method of making a crease at the edge of the sheet perpendicular to the direction of travel. Crease sound formation all 4? How to straighten sheets of paper. (2) A table on which a sheet is placed, a reversing device for folding the sheet into a YTR shape on the table and reversing it, and a bending device for folding the sheet by the reversing device. A sheet straightening device equipped with a pressure device that presses down onto a table from above.