JP3564265B2 - Flexographic printing machine - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a flexographic printing press equipped with a device for reliably and efficiently performing ink exchange accompanying an order change.
[0002]
[Prior art]
The flexographic printing press is a rotary printing press that prints a rubber or synthetic resin letterpress using an inking roll called anilox roll and a quick-drying ink. Here, FIG. 5 is a perspective view illustrating an ink supply method and an ink cleaning method of a general flexographic printing press, FIG. 6 is a perspective view showing a configuration of an ink roll section in the flexographic printing press, and FIG. FIG. 4 is a schematic side view illustrating a configuration of a roll unit.
[0003]
As shown in FIG. 5, a flexo ink 18 of such a flexographic printing press is provided with an ink reservoir formed by a nip portion 2 between an anilox roll 1 and a rubber roll 17 from an ink container 14a through an ink pump 11 through a supply pipe 12. Supplied to
Next, the flexographic ink 18 supplied to the nip portion 2 is leveled (doctored) by the rubber roll 17 and uniformly transferred to the anilox roll 1, and further transferred from the surface of the anilox roll 1 to a printing cylinder (not shown). Transferred to the stamped plate. In addition, predetermined printing is performed on the corrugated cardboard sheet by contacting the printing plate.
By the way, during the printing operation, the flexographic ink 18 is always supplied to the nip portion 2, and the excess ink 18 overflows from both ends of the nip portion 2, flows down to the end pans 19a, 19b, and further flows out of the discharge pipes 13a, 13b. Through the ink container 14a. In this way, continuous printing of the flexographic ink 18 enables continuous printing.
[0004]
Next, ink exchange accompanying an order change or the like will be described.
The flexographic printing press changing device includes an ink circulating supply device that circulates ink between the above-described ink container 14a and an ink reservoir formed by a combination of the rubber roll 17 and the anilox roll 1 and supplies ink to the ink roll portion. The apparatus includes a cleaning liquid supply device for supplying the cleaning liquid to the circulation path, an exchange mechanism for operating the ink circulation supply device and the cleaning liquid supply device in a predetermined procedure, and the like.
As a procedure for ink replacement, first, the ink pump 11 is stopped, and thereby the ink circulation in the ink circulation path is stopped. Next, the leading ends of the ink supply pipe 12 and the discharge pipe 13 are raised, and the ink supply pipe 14a is kept in a standby state immediately above the connection ports 15 and 16 located above the ink container 14a, and the nip portion between the rubber roll 17 and the anilox roll 1 is held. 2 and the flexo ink 18 in the ink circulation path is collected into the ink container 14a after waiting for spontaneous outflow.
[0005]
Then, the lower end of the ink supply pipe 12 and the lower end of the discharge pipe 13 are moved to a predetermined position above the bucket 20 in response to the recovery end signal, and the solenoid valve 21 of the ink cleaning device is operated to supply the cleaning liquid 22. Clean the circulation supply path.
Next, the operation of the electromagnetic valve 21 is stopped to stop the supply of the cleaning liquid 22 in the ink circulation path, and the nip portion 2 between the rubber roll 17 and the anilox roll 1 and the cleaning liquid 22 in the ink circulation path are waited for spontaneous outflow. Let it drain up.
Then, upon receiving a signal indicating the end of the collection operation by the timer, the process proceeds to the return step, that is, the leading ends of the ink supply pipe 12 and the discharge pipe 13 are connected to the connection ports 15 and 16 of the next-order ink container 14b by the exchange mechanism.
When the ink pump 11 is started in this state, the flexo ink 18 of the next order circulates through the ink circulation supply path as described above, and the next printing can be performed.
[0006]
In these conventional devices, the ink collection of the current order accompanying the ink exchange, the discharge of the cleaning liquid required for the cleaning operation, and the like are all based on natural outflow. For this reason, the processing of the flexographic ink 18 and the cleaning liquid 22 remaining in the nip portion 2 between the rubber roll 17 and the anilox roll 1 takes a lot of time, which is a major factor in reducing the production efficiency. In addition, a small amount of the ink roll nip portion always remains and mixes with the next ink, which causes quality deterioration and other various problems.
[0007]
Therefore, in order to cope with the above-mentioned problem, while sliding on the nip portion 2 between the anilox roll 1 and the rubber roll 17 as shown in FIGS. 6 and 7, it reciprocates along the surface length of the rolls 1 and 17 (axial direction). A flexographic printing press provided with a movable liquid discharge / elimination block 3 has been proposed (Japanese Utility Model Laid-Open No. 63-77736).
In the illustrated device, a motor 5 fixed to the device frame via the bracket 4, a sprocket 6 fixed to the shaft end of the motor 5, a mounting bracket 8 opposed to the other device frame in the device width direction, and A driving device is constituted by a sprocket 9 rotatably mounted via a shaft 7 and a chain 10 bridged between the sprockets 6 and 9. It is fixed to a part. Therefore, the liquid exclusion block 3 can reciprocate in the axial direction of the anilox roll 1 via the sprockets 6, 9 and the chain 10, corresponding to the forward and reverse rotation of the motor 5. In addition, as a driving device of the liquid exclusion block 3, various methods such as a slide rail, a rack and a pinion other than those illustrated can be adopted (not shown).
[0008]
Next, the function of the device will be described. That is, ink exchange is performed according to the following procedure under the above configuration.
As shown in FIGS. 5 to 7, first, the ink pump 11 is stopped to stop the ink circulation in the ink circulation path, and the tips of the ink supply pipe 12 and the discharge pipe 13 are connected to the connection port 15, which is located above the ink container 14 a. Stand by just above 16. Next, the motor 5 is driven to slide the liquid removing block 3 back and forth along the nip portion 2 between the rubber roll 17 and the anilox roll 1 for a predetermined time. During this time, the anilox roll 1 and the rubber roll 17 are stopped or running at low speed, and the ink 18 remaining in the nip portion 2 is scraped off by the liquid removing block 3 and is forcibly pushed out to both ends of the rolls 1 and 17. The ink is collected in the end pan 19 and is collected in the ink container 14a through the discharge pipe 13.
After the ink collection is completed, the lower ends of the ink supply pipe 12 and the discharge pipe 13 are moved to predetermined positions above the bucket 20, and then the solenoid valve 21 of the ink cleaning device is operated to clean the ink circulation supply path. Subsequently, the operation of the solenoid valve 21 is stopped to stop the supply of the cleaning liquid 22 in the ink circulation path, and the motor 5 is driven for a predetermined time to slide the liquid exclusion block 3 back and forth. During this time, the anilox roll 1 and the rubber roll 17 are stopped or running at low speed as in the case of ink recovery, and the cleaning liquid 22 remaining in the nip portion 2 is scraped off and forcibly pushed out to both ends of the rolls 1 and 17, and the end It is collected in the pan 19 and discharged into the bucket 20 through the discharge pipe 13. The liquid elimination block 3 functions as described above, whereby the nip 2 between the rubber roll 17 and the anilox roll 1 and the ink 18 remaining on the surfaces of the rolls 1 and 17, which have conventionally caused the largest loss time, The time required for collecting and discharging the cleaning liquid 22 can be reduced.
[0009]
[Problems to be solved by the invention]
However, in the above-described apparatus, the end of the rolls 1 and 17 is maintained in a state where the liquid removing block 3 used for forcibly discharging the flexographic ink 18 and the cleaning liquid 22 is operated, that is, in a state where a part of the old order ink remains on the surface. Was waiting to go up. For this reason, when the next order of ink is supplied or when the liquid elimination block 3 is operated at the time of the next order change, the adhered and remaining ink dissolves into the next order of ink having a different color and is mixed with each other to change color. (Contamination), and there is a problem that print quality is remarkably reduced.
[0010]
The present invention has been made in view of such circumstances, and its purpose is to completely prevent the ink of the old order from adhering and remaining on the surface due to the complete cleaning of the liquid exclusion block. To provide a flexographic printing press capable of performing high-quality printing by preventing ink denaturation caused by mixing of an old order ink with an existing order ink when exchanging the ink and further collecting the ink. It is in.
[0011]
[Means for Solving the Problems]
In order to solve the problems of the related art, the present invention includes an ink supply device configured to form an ink reservoir by a pair of rolls that are in contact with each other, and an ink cleaning device that cleans the ink path. In a flexographic printing press provided with a liquid exclusion block that can reciprocate in the axial direction of the roll and that can move up and down in contact with the roll peripheral surface, and a cleaning device that cleans the liquid exclusion block, A cleaning device is provided at one end of the liquid rejection block in the reciprocating direction and above the ink collecting end pan, and provided with a cleaning brush, a cleaning liquid ejecting unit, and a seal brush for preventing scattering of the cleaning liquid. The box is provided .
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail based on illustrated embodiments.
[0013]
1 to 4 show an embodiment of a flexographic printing press according to the present invention. Here, FIG. 1 is a schematic configuration view of a flexographic printing press according to an embodiment of the present invention, FIG. 2 is a schematic side view thereof, and FIG. FIG. 4 is a view for explaining the configuration and functions of the cleaning device, and FIG.
[0014]
As shown in FIGS. 1 and 2, the flexographic printing press according to the embodiment of the present invention includes a scraping-type ink collecting and cleaning apparatus equipped with the liquid removing block 3 described in the section of the related art. A cleaning device 23 is provided.
The liquid exclusion block 3 is in sliding contact with the roll nip portion 2 between the pair of anilox rolls 1 and the rubber roll 17 that are in contact with each other, that is, in contact with the peripheral surfaces of the rolls 1 and 17 located above the roll nip portion 2 in the roll axial direction. It is arranged so that it can reciprocate and move up and down.
For this reason, the lower part of the liquid exclusion block 3 is formed in a substantially triangular shape cut out in a direction facing each other at a part of an arc corresponding to the roll peripheral surface of the roll nip portion 2. The upper part of the liquid exclusion block 3 is attached to a rail 29 via an elevating means supported by a moving device (not shown) in the roll axis direction, for example, an air cylinder 28. The air cylinder 28 can be moved up and down at an arbitrary timing.
[0015]
On the other hand, as shown in FIGS. 3 and 4, the cleaning device 23 for the liquid exclusion block 3 is located at the downstream (one side) end in the moving direction of the liquid exclusion block 3 and above the ink recovery end pan 19. One end of the discharge pipe 13 is connected to the bottom of the end pan 19. The cleaning device 23 includes a cleaning brush 24 having a plurality of brushes 24a, 24b, a cleaning box 27 provided with a plurality of sets of cleaning liquid jet nozzles 25, seal brushes 26a, 26b for preventing the cleaning liquid 22 from scattering, and the like. Have been.
[0016]
In the cleaning device 23 having the above structure, the ink 18 formed in the roll nip 2 between the anilox roll 1 and the rubber roll 17 and the cleaning liquid 22 for cleaning the ink 18 in the ink reservoir. Is forcibly discharged by the liquid exclusion block 3, and then the liquid exclusion block 3 is sent to the installation location of the cleaning device 23 via a moving device such as a rail 29.
Thereafter, in the cleaning device 23, the high-pressure cleaning liquid 22 is injected from the injection nozzle 25, and the liquid exclusion block 3 is moved up and down by the air cylinder 28. As a result, the ink 18 remaining on the liquid exclusion block 3 is completely removed by the washing with the cleaning liquid 22 and the scraping action of the cleaning brush 24.
[0017]
Further, scattering of the cleaning liquid 22 to the outside due to the ejection is regulated by the side walls constituting the cleaning device 23 and the seal brushes 26a and 26b provided on the carry-in side of the liquid removing block 3, and the ink collecting end located below. It falls into the pan 19 and is collected. Then, similarly to the recovery of the cleaning liquid 22, the cleaning liquid 22 is discharged from the end pan 19 through the discharge pipe 13 into the bucket 20. After the cleaning, the liquid removal block 3 is moved to the same position or to a predetermined standby position, and waits until the next operation according to the order change.
[0018]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made based on the technical idea of the present invention.
[0019]
【The invention's effect】
As described above, the flexographic printing press according to the present invention includes an ink supply device configured to form an ink reservoir by a pair of mutually contacting rolls, and an ink cleaning device that cleans the ink path. contact with reciprocable in the axial direction of the roll, and provided with a vertically movable liquid elimination block, which provided a cleaning device for cleaning the liquid exclusion block, the cleaning apparatus of the liquid exclusion block, the a the reciprocating direction of the one end of the liquid exclusion block, located above the ink collecting end pans, cleaning brush, provided with a washing box having a seal brush to prevent scattering of the cleaning liquid injection means and wash This eliminates the problem that ink of the old order remains on the surface due to the complete cleaning of the liquid exclusion block. When the ink is replaced with another ink, and the same ink is further recovered, it is possible to prevent the denaturation (decrease in viscosity and color contamination) of the ink caused by mixing the old order ink with the current order ink. As a result, high quality printing can be performed.
The reason is that, in the case of flexographic printing presses, order change (color change) is usually performed frequently, so shortening the ink replacement time greatly affects productivity, and preventing ink denaturation reduces print quality. This is because it is the most important factor to keep high.
[Brief description of the drawings]
FIG. 1 is a front view showing a schematic configuration of a flexographic printing press according to an embodiment of the present invention.
FIG. 2 is a side view showing a schematic configuration of the flexographic printing press in FIG.
FIG. 3 is a side view schematically showing a cleaning unit of a liquid removing block provided in the ink collecting and cleaning device of the flexographic printing press.
FIG. 4 is a view taken in the direction of arrows AA in FIG. 3;
FIG. 5 is a perspective view illustrating an ink supply method and an ink cleaning method of a general flexographic printing press.
FIG. 6 is a perspective view showing an ink roll section in a conventional flexographic printing press.
FIG. 7 is a schematic side view showing an ink roll section in FIG. 6;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Anilox roll 2 Roll nip part 3 Liquid exclusion block 13 Discharge pipe 17 Rubber roll 18 Ink 19 End pan 20 Bucket 22 Cleaning liquid 23 Cleaning device 24 Cleaning brush 25 Cleaning liquid injection nozzle 26 Seal brush 27 Cleaning box 28 Air cylinder (elevating means)

Claims (1)

An ink supply device comprising an ink reservoir formed by a pair of rolls in contact with each other and an ink cleaning device for cleaning the ink path are provided, and are capable of reciprocating in the axial direction of the roll in contact with the roll peripheral surface on the upper side of the roll nip. In addition, in the flexographic printing press provided with a liquid exclusion block that can be moved up and down and a cleaning device for cleaning the liquid exclusion block, the cleaning device for the liquid exclusion block is provided at one end in the reciprocating direction of the liquid exclusion block. A flexographic printing press comprising a cleaning box , which is located above an ink recovery end pan and is provided with a cleaning brush, a cleaning liquid ejecting unit, and a seal brush for preventing scattering of the cleaning liquid.

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