JPH0852858A - Device for supplying powder for preventing set-off - Google Patents

Abstract

PURPOSE:To enhance the adhesion of a powder on a printing surface and reduce the spraying amount of the powder by arranging a spraying device for spraying the set-off preventing powder on the printing surface of flat paper and an atomizer, which sprays water in a fog state for the set-off preventing powder sprayed with a spraying device in the delivery part of a flat-paper printing press. CONSTITUTION:When flat paper 11 travels in a delivery part by the movement of a printing press, set-off preventing powder 10 is sprayed on a printing surface 11a of the flat paper 11 from a spraying device 12. At the same time, the atomized water 13 is injected toward the powder 10 from an atomizer 14. The water film is formed around individual particles of the powder 10. Thus, the individual particles of the powder 10 are attached to the printing surface 11a of the flat paper 11 by the absorbing force of the film of the water 13. The powder 10 is attached to both the marked part, to which ink is attached, at the printing surface 11a and the non-marked part, to which the ink is not attached, and the set-off of the ink is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for supplying settling prevention powder in a sheet-fed printing press.

[0002]

2. Description of the Related Art Sheets immediately after printing, which are discharged to a delivery section of a sheet-fed printing press, are vertically stacked to form a so-called rod-stacked state. However, in such a bar-stacked state, the ink is transferred to the inside of the sheet, which causes printing stains. Conventionally, in order to prevent this, powders of starch, calcium carbonate, etc. are sprinkled on the printing surface of the sheet. That is, the powder is sprinkled on the printing surface while the sheet comes out of the printing unit and reaches the bar stacking position, and the powder is attached to the image area and the non-image area of the print surface. The powder forms an air gap between the sheets of paper in the stacked state, prevents the ink of one adjacent sheet from adhering to the other sheet, and prevents set-off.

[0003]

However, in the prior art, a large amount of powder is sprayed to ensure that the powder adheres to the printing surface, so the powder excessively adheres to the printing surface, degrading the print quality, and It is scattered around and pollutes the work environment. In addition, the powder easily drops on the printing surface, and the powder that has fallen off adheres to the blanket cylinder of the printing unit when printing the back surface of the sheet, for example, and causes printing stains. .

It is an object of the present invention to provide a settling-prevention powder supply device capable of solving such problems.

[0005]

In order to achieve the above object, the present invention provides a spreader for spreading settling prevention powder on a printing surface of a sheet, and a settling prevention powder spread by the spreader. An atomizer that atomizes and sprays water against powder,
Adopting the configuration of the set-off prevention powder supply device arranged in the delivery section of the sheet-fed printing press, and spreading the set-off prevention powder on the printing surface of the sheet, and the spreader. With an atomizer that sprays water into the printing surface of the sheet before spraying the set-off prevention powder.
The configuration of the settling prevention powder supply device is provided in the delivery section of the sheet-fed printing press.

[0006]

With the settling prevention powder supply device according to the present invention, the settling prevention powder adheres to the printing surface of the sheet via water, so that the adhesion of the powder to the printing surface is increased. The amount of powder sprayed can be reduced accordingly. Therefore, prevent the powder from excessively adhering to the print surface, prevent the print quality from deteriorating, minimize the scattering to the surroundings, prevent the work environment from contaminating, and prevent the powder from dripping on the print surface. can do.

Further, since water is atomized by an atomizer and jetted, it is possible to prevent the water from excessively adhering to the powder or the printing surface. Therefore, an appropriate amount of powder can be attached to the printing surface as a thin film, and rusting of the printing machine can be prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a settling prevention powder supply device according to the present invention will be described below with reference to the drawings.

Embodiment 1 A sheet-fed printing press has a delivery section 2 as shown in FIG.
Is provided behind the printing unit 1. The printing unit 1 has a printing unit corresponding to the number of printing colors, and in the case of an offset printing machine, each printing unit is provided with a plate cylinder 3, a blanket cylinder 4 and an impression cylinder 5. The delivery unit 2 is a device for receiving the sheets discharged from the final printing unit of the printing unit 1, and the paper take-up cylinder 6 adjacent to the impression cylinder 5 of the final printing unit.
A paper receiving stand 7 for receiving the discharged sheets and putting them in a stacked state, an endless delivery chain 8 running from near the paper pick-up cylinder 6 to above the paper receiving stand 7, and a delivery chain 8 has a delivery claw 9 provided on it.

Thus, the sheet passes between the blanket cylinder 4 and the impression cylinder 5 and when the final color is printed, the impression cylinder 5
Is delivered to the paper take-up cylinder 6 and further delivered to the delivery claw 9 of the delivery chain 8. Delivery chain 8
Is traveling at a constant speed, and the sheet is conveyed above the paper receiving tray 7 by the delivery chain 8, released from the delivery claw 9, and discharged onto the paper receiving tray 7. The sheets are successively dropped onto the paper tray 7 and are piled up in a stack. Sign 1
7 shows such a pile of stacked sheets.
The paper tray 7 is hung on the frame 2a of the delivery unit 2 via a chain and a sprocket wheel, and is lifted and lowered according to the stacking height of the sheets.

The sheet output from the printing unit 1 is placed by a delivery chain 8 so that the printing surface of the sheet is on the upper side.
It is designed to be conveyed upward, and a device for supplying the settling prevention powder to the printing surface of the sheet is provided on the conveying path. That is, FIG. 1 and FIG.
As shown in (A), the settling prevention powder 10 is sprayed on the printing surface 11a of the sheet 11, and the settling prevention powder 10 sprayed by the spreader 12 is mixed with water 13 And an atomizer 14 for atomizing and ejecting the mist are disposed on the traveling path of the delivery chain 8 in the delivery section 2.

The spreader 12 has a cylindrical body 12a which is bridged between the left and right frames 2a of the delivery section 2 and the cylindrical body 12a.
And a plurality of nozzles 12b attached at regular intervals. Inside the cylindrical body 12a, the settling prevention powder 1
0 is injected, and air is sent to the nozzle 12b from a compressor or the like.
The powder 10 is carried by the air flow ejected from the nozzle 12b.
Will be ejected toward the printing surface 11a.

The atomizer 14 has a cylindrical body 14a which is bridged between the left and right frames 2a of the delivery section 2 in the vicinity of the sprinkler 12 and a plurality of cylindrical bodies 14a which are attached to the cylindrical body 14a at regular intervals. It has a nozzle 14b. In this case, the nozzle 14b is arranged so as to face the powder 10 sprayed from the nozzle 12b of the sprayer 12. As shown in FIG. 3, water is supplied from the water tank 15 to the cylindrical body 14a.
3 is supplied, and air is sent to the nozzle 14b from a compressor or the like.
The water in the water tank 15 is mixed with an antistatic agent, silicon, etc. at a ratio of about 2%, and is supplied into the cylindrical body 14a after dust and the like are removed by a filter 16 such as a suction filter. It is like this. The antistatic agent removes static electricity from the sheets 11, and silicon is added to improve slippage between the sheets 11 when the sheets 11 are stacked on the stick. Air filter 18
And a solenoid valve 19 to reach the nozzle 14b. When a predetermined control signal is sent to the solenoid valve 19 and the valve is opened, it flows toward the nozzle 14b, and jets from the nozzle 14b to eject the water tank. Atomize the water 13 from 15. The control signal is generated, for example, when an operator operates an operation button of a settling prevention powder supply device arranged on a control panel of the printing press.

By the operation of the printing machine, the sheet 11
When traveling in the delivery unit 2, the powder 10 is sprayed from the sprayer 12 toward the printing surface 11a of the sheet 11, and at the same time, the atomized water 13 is sprayed toward the powder 10 from the atomizer 14. A film of water is formed around the individual particles of the powder 10. As a result, as shown in FIG.
It is attached to the printing surface 11a of the sheet 11 by the suction force of a. The powder 10 is the ink 2 on the printing surface 11a.
The ink adheres to both the image area where 0 is attached and the non-image area where the ink 20 is not attached, and prevents the set-off of the ink 20.

Embodiment 2 As shown in FIG. 2 (B), this settling prevention powder feeding device is provided with a settling prevention powder 10 in a sheet 1.
1. The sprayer 12 for spraying on the printing surface 11a of No. 1 and the sprayer 1
The delivery unit 2 is provided with an atomizer 14 that atomizes and sprays water 13 onto the printing surface 11a of the sheet 11 before the settling prevention powder 10 is sprayed by 2.

In the case of this embodiment, the spray of water 13 adheres to the printing surface 11a before the powder 10 and adsorbs the powder 10 to be dispersed later. Also in this case, the powder 10 adheres to both the image area where the ink 20 is attached and the non-image area where the ink 20 is not attached on the printing surface 11a,
Prevent the set-off of the ink 20.

[0017]

EFFECTS OF THE INVENTION According to the present invention, the settling prevention powder adheres to the printing surface of the sheet through water, so that the adhesion of the powder to the printing surface is increased and the amount of the powder sprayed is reduced accordingly. be able to. Therefore, to prevent the powder from excessively adhering to the printing surface, prevent the print quality from deteriorating, and to prevent scattering to the surroundings to prevent contamination of the work environment. It is possible to prevent defects. In addition, it is possible to prevent the powder from dripping on the printing surface, and to prevent printing stains due to the dripping powder adhering to the blanket cylinder or the like. Furthermore, since it uses water,
It is also possible to remove static electricity from the sheets.

Further, since the water is atomized by the atomizer and jetted, it is possible to prevent the water from excessively adhering to the powder or the printing surface. Therefore, an appropriate amount of powder can be attached to the printing surface as a thin film, and rusting of the printing machine can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic side view of a delivery section of a sheet-fed printing press provided with a settling prevention powder supply device according to the present invention.

FIG. 2A is a schematic side view showing a disposition state of a sprinkler and an atomizer, and FIG. 2B is a schematic side view showing another disposition state of the sprinkler and the atomizer.

FIG. 3 is a block diagram showing a path for supplying water and air to the atomizer.

FIG. 4 is a schematic view showing a state in which a settling prevention powder is attached to a printing surface of a sheet.

[Explanation of symbols]

 2 ... Delivery part 10 ... Settling prevention powder 11 ... Sheet 11a ... Printing surface 12 ... Spreader 13 ... Water 14 ... Atomizer

Claims (2)

[Claims] 1. A spreader for spraying a set-off prevention powder on a printing surface of a sheet, and an atomizer for spraying water into the set-off prevention powder sprayed by the spreader. But,
A settling prevention powder supply device, which is arranged in the delivery section of a sheet-fed printing press. 2. A spreader for spraying the set-off prevention powder on the printing surface of the sheet, and water before the set-off prevention powder is sprayed by the spreader. An apparatus for supplying settling prevention powder, characterized in that an atomizer for spraying in a sheet shape is arranged in the delivery section of a sheet-fed printing press.