JP2930468B2 - Ink supply circulation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink supply and circulation apparatus for a flexographic printing press equipped with a two-roll ink roll for a cardboard sheet making machine and the like. The present invention relates to a novel ink supply / circulation device which improves the supply and ink cleaning methods.

[0002]

2. Description of the Related Art FIGS. 9 and 10 are schematic explanatory diagrams of a conventional flexographic printing press. As shown in FIG. 9, the ink is supplied from the ink container 16 a to the substantially axial center of the nip formed by the anilox roll 4 and the rubber roll 1 via the ink supply pipe 17. After the ink supplied to the nip portion flows to both ends of the roll, the ink is moderately doctored by the rubber roll 1 and uniformly spread on the outer peripheral surface of the anilox roll 4. Is transferred to the printing plate 10 wound on the plate cylinder 9 as shown in FIG. Subsequently, the ink supplied to the printing plate 10 is transferred to a corrugated cardboard sheet 12 running synchronously with an impression cylinder 11 located below. In the drawing, reference numerals 18a and 18b denote feed rolls which hold the cardboard sheet 12 and transfer it downstream at a predetermined timing.

The outer peripheral surface of the anilox roll 4 is a straight roll having a sculpture (irregularities), while the outer peripheral surface of the rubber roll 1 is wound with rubber having a predetermined hardness in a crown shape (taiko shape). 6, 7, and 8
FIG. 3 is an explanatory view of a contact surface shape formed at a nip portion between the anilox roll 4 and the rubber roll 1. The ideal nip pressure is determined by the specifications (rubber hardness, crown amount) of the rubber roll 1. A predetermined pressure is applied by the rotation of an eccentric bearing that supports both ends of the rubber roll 1 and pressurized until the contact width W between the anilox roll 4 and the rubber roll 1 becomes uniform in the axial direction as shown in FIG. It is common to use the rubber roll core (core bar) and rubber in a deformed (flexed) state. In other words, when over-contact or contact pressure is insufficient, FIG.
As illustrated in (c), the contact width W in the roll axis direction
And the ink density varies in the width direction of the printed matter. Therefore, it is important to select and combine appropriate anilox rolls 4 and rubber rolls 1 in order to match the printing density with the printing specifications.

[0004] However, conventional flexographic printing presses are usually provided with only one pair of ink rolls 1 and 4 for one set of printing units, and have various printing specifications (for example, solid printing, bar code printing, and so on). (Such as cosmetic printing) could not respond to all. As described above, the conventional printing press has a special mechanical characteristic capable of coping only with a specific printing, and the only way to change the printing specifications is to replace one or both sides of the anilox roll 4 and the rubber roll 1 together. Was.

On the other hand, ink exchange accompanying an order change has been performed as follows. The procedure for ink replacement is as follows: first, the supply of ink is stopped by stopping the pump 19, and then the ink in the ink supply pipe 17 is caused to flow out, and at the same time, the ink that has naturally flowed out of the nip portion between the rolls 1 and 4 is discharged into the end pan 20a. 20b, the ink is collected in the ink container 16a via the return pipe 21. Subsequently, the solenoid valve 22 is closed, the engagement between the ink supply pipe 17 and the end of the return pipe 21 is released from the ink container 16a, and after the cylinder is moved onto the bucket 13 by the suction operation of the cylinder, the solenoid valve 23 on the cleaning liquid side is opened. By driving the pump 19, the cleaning liquid is supplied to the nip portion between the anilox roll 4 and the rubber roll 1, which is set to keep rotating at a low speed, similarly to the above-described ink.

The above-mentioned anilox roll 4 and rubber roll 1
The outer peripheral surface of the roll is cleaned, and the cleaning liquid flowing out from both ends of the nip portion of the roll is supplied to the end pans 20a and 20b and the return pipe 21.
Through the bucket 13 to be collected. Subsequently, the operation of the pump 19 is stopped, and the electromagnetic valve 23 is closed to collect the cleaning liquid in the ink path and the pump 19 into the bucket 13 by natural outflow. Next, the lower end of the ink supply pipe 17 and the lower end of the ink return pipe 21 are connected to the connection port of the ink container 16b of the next order, the solenoid valve 22 is opened, and the pump 19 is opened.
Is started, the ink is supplied to the roll nip again as described above, and the next printing can be performed. The ink supply and circulation device of the conventional flexographic printing press has the above-described configuration and functions, but has various disadvantages described below.

[0007]

As described in the section of the prior art, a conventional flexographic printing press equipped with a two-roll type ink roll has two ends of a rubber roll supported by eccentric bearings. A method of adjusting the nip pressure by changing the distance between the roll axes has been employed. That is, the outer peripheral surface of the rubber roll is formed in a crown shape on the premise of deformation of the roll core (metal core), and is set so that the contact width becomes uniform over the entire axial direction when the center portion is deformed by a predetermined amount. Therefore, the best (no shading) set pressure is only one point, the pressure increase / decrease range is small (non-uniform in the axial direction), and the degree of ink squeezing (the amount of ink transferred onto the printing plate) is adjusted. Is impossible. In addition,
When squeezing the ink, if the roll diameter is increased to withstand the increase in the pressing force, the pressing force between the ink rolls (kg / c
m) (Linear pressure) is difficult to draw because it is difficult to obtain. Conversely, if the roll diameter is reduced, bending deformation increases, and the condition such as the amount of ink transfer in the axial direction fluctuates (shading phenomenon occurs).

[0008] Further, regarding the ink exchange accompanying the order change, the ink is supplied to the nip portion of the ink roll (anilox roll and rubber roll) and the ink is exchanged after waiting for the natural outflow. The entire area such as bread cannot be cleaned cleanly, and ink residue gradually accumulates, and eventually the return pipe and the like are clogged. In addition, there is a disadvantage that it takes much time for cleaning. SUMMARY OF THE INVENTION The present invention proposes an ink supply and circulation device capable of obtaining a uniform pressing force with less bending deformation of a rubber roll core, and aims to solve the above-mentioned conventional problems.

[0009]

SUMMARY OF THE INVENTION Therefore, the present invention provides a two-roll type flexographic printing press which squeezes ink with an anilox roll and a rubber roll and transfers the ink from the anilox roll to a printing plate wound on a plate cylinder. In the ink supply and circulation device to be installed, the device includes a receiving table that slides over the entire area of the rubber roll in the axial direction, a unit that enables the rubber roll to be integrally connected to and separated from the anilox roll, and ink that adheres to the rubber roll from the receiving ink reservoir. For transferring and transferring to the outer peripheral surface of the anilox roll brought into contact with the other side of the rubber roll, cleaning means for the rubber roll and the anilox roll, and a pan for recovering the ink and the cleaning liquid. Means.

[0010]

According to the present invention, the rubber roll core (metal core) is free from bending deformation, and a uniform pressing force (ink squeezing pressure) can be obtained over the entire width direction of the apparatus. Since the diameter of the rubber roll can be reduced, the ink can be easily squeezed, and line printing which tends to occur in the two-roll system can be prevented. Ink squeezing amount (nip pressure between rubber roll and anilox roll) can be arbitrarily controlled. In addition, it is possible to forcibly and strongly wash the ink with a strong water pressure, so that it is possible to greatly reduce the time required for replacing the ink washing, and at the same time, it is possible to wash the entire surface neatly and to prevent the accumulation of ink residue.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an ink supply and circulation device according to the present invention; FIG. First, the structure will be described with reference to FIGS. 1 and 2. The ink roll portion of the ink supply and circulation device is a pressurizing auxiliary for supporting both shaft ends of the rubber roll 1 via eccentric bearings 2a and 2b as shown in FIG. Cradle 3 as a tool
And a rubber roll 1, which form a rubber roll unit. The rubber roll is configured to be prevented from being deformed in the entire axial direction by the receiving table. Further, the rubber roll unit is formed so as to be movable on the anilox roll 4, and the rubber roll 1
The state of engagement with the anilox roll can be adjusted. In addition, as shown in FIG. 1, the apparatus is provided with a blade 5 configured to be able to contact and separate from the anilox roll 4 in parallel.

Washing liquid jets 6a and 6b are provided above an engaging portion between the receiving base 3 and the rubber roll 1 and an engaging portion between the rubber roll 1 and the anilox roll 4, and furthermore, a connection between the receiving base 3 and the rubber roll 1 is provided. An ink supply port 7 is provided above the joint portion and upstream of the inclined nip portion.
In the drawing, reference numeral 8 denotes an ink pan which covers a unit constituted by the pedestal 3 and the rubber roll 1 and the like over the front, rear and both sides to wash and collect ink, and both sides are shielded by the pedestal 3 side plate. Also, the ink is squeezed through the rubber roll 1 and the anilox roll 4 and transferred from the anilox roll 4 to the printing plate 10 wound on the outer peripheral surface of the plate cylinder 9, whereby the impression cylinder 11 juxtaposed below the plate cylinder 9 is provided. The basic functions of the flexographic printing press for printing on the sheet 12 traveling between the spaces are the same as those described in the section of the related art.

Next, the operation of the embodiment constructed as described above will be described. In this embodiment, the rubber roll 1 is rotated by the eccentric bearings 2a and 2b which support the rubber roll 1.
After appropriately adjusting the contact pressure between the rubber roll 1 and the anilox roll 4, the nip pressure between the rubber roll 1 and the anilox roll 4 is adjusted by setting the contact pressure between the rubber roll 1 and the anilox roll 4 via a moving means (not shown). . The ink is supplied from the ink supply port 7 to the ink reservoir of the engagement portion between the rubber roll 1 and the receiving table 3,
By rotating the rubber roll 1 in the direction of the arrow, a necessary minimum amount is transferred and supplied to the anilox roll 4.

Next, a description will be given of the ink exchange accompanying the order change. Current order ink is rubber roll 1
The cleaning liquid jets 6a, 6 provided above the engaging portion and above the engaging portion between the rubber roll 1 and the anilox roll 4 after being naturally flown out of the inclined surface formed in the engaging portion of the receiving table 3 and collected.
The surface is cleaned by powerful and forced spraying of the cleaning liquid from b. At the same time, the ink supply port 7 and the in-pipe blade 5 are also washed by the supply of the washing liquid, and both washing liquids are simultaneously collected into the bucket 13 via the blade 5 and the pan 8 brought into contact with the anilox roll 4. At this time, the rubber roll 1 and the anilox roll 4 are rotated at an appropriate speed (low speed). The scattering of the cleaning liquid to be sprayed is caused by the cover 8 provided on the receiving stand 3 and the side plate 15 of the receiving stand 3.
It can be prevented by.

The present invention is constructed and functions as described above. Since the deflection of the rubber roll 1 is supported by the receiving table 3 which is brought into contact with the entire area in the axial direction, the deflection may be concerned even if the diameter of the rubber roll 1 is reduced. This eliminates the necessity, and also makes it easier to squeeze the ink, thereby eliminating the drawbacks of conventional printing such as stripe printing. In connection with the above, as shown in FIG. 5, even when the nip width between the rubber roll 1 and the anilox roll 4 is changed, the rubber roll becomes a thread-wound type [FIG.
(B)] or a tall shape (FIG. 8 (c)), and the ink density can be balanced in the axial direction. As a result the printing unevenness can be eliminated, and will be able to control aperture (the ink film thickness) of the ink amount by the adjustment of the nip pressure, beautification printing, bar code printing, Ru can accommodate solid printing such a wide variety of printing specifications. Contact name present invention is not limited to the above embodiments, but that various changes and modifications may be made without departing from the scope and spirit of the present invention.

[0016]

As described above the present invention exhibits, is provided with the sliding contact cradle over the entire axial range of the rubber roll which engages the A two Rocks roll, is possible to add a uniform ink squeezing pressure in the device width direction with it, squeezing of ink made smaller diameter rubber Mro <br/> Le is facilitated (often squeezable manner), 2 streaks printing was a disadvantage of roll type can be prevented. Matthew Nki aperture value it is possible to arbitrarily adjust the (nip pressure between rolls), Therefore it is an ink film thickness control, solid printing, bar code printing and can cope with beautification printing a wide variety of printing specification Both
To, forced, month enables powerful cleaning, but exert an equal excellent effects that can be shortened ink wash-exchange time.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view of an ink supply and circulation device according to the present invention.

FIG. 2 is a detailed plan view of a main part of FIG.

FIG. 3 is a plan view of a rubber roll of the ink supply and circulation device according to the present invention.

FIG. 4 is a side sectional view of the rubber roll portion of FIG. 1;

FIG. 5 is an explanatory diagram of an operation of a rubber roll.

FIG. 6 is a front view of a rubber roll of the conventional ink supply and circulation device.

FIG. 7 is a side sectional view of a rubber roll portion of a conventional device.

FIG. 8 is an explanatory view of a defect of a conventional rubber roll portion.

FIG. 9 is a perspective view of an ink supply and circulation device of a general flexographic printing press.

FIG. 10 is a sectional view taken along line AA of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rubber roll 2 Eccentric bearing 3 Cradle 4 Anilox roll 5 Blade 6 Cleaning liquid ejection port 7 Ink supply port 8 Ink pan 9 Plate cylinder 10 Printing plate 11 Impression cylinder 12 Corrugated cardboard sheet 13 Bucket 14 Cover 15 Side plate 16 Ink container 17 Ink supply pipe 18 Feed Roll 19 Pump 20 End pan 21 Return pipe 22, 23 Solenoid valve

Claims (1)

(57) [Claims] 1. An ink supply and circulating apparatus for a two-roll type flexographic printing machine for squeezing ink with an anilox roll and a rubber roll and transferring the ink from the anilox roll to a printing plate wound on a plate cylinder. Is a cradle that slides over the entire area of the rubber roll in the axial direction, means for enabling the rubber roll to be integrally connected to and separated from the anilox roll, and ink attached to the rubber roll from the cradle ink reservoir to the other side of the rubber roll. An ink supply and circulating apparatus comprising: means for transferring and supplying to an outer peripheral surface of an anilox roll in contact therewith; means for cleaning a rubber roll and an anilox roll; and a pan for recovering ink and a cleaning liquid.