JPH0756195Y2 - Ink supply device for flexographic printing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an ink supply device in a flexographic printing machine, and in particular, it includes an anilox roll and a rubber roll.
The present invention relates to a mechanism for lubricating and sealing (preventing ink leakage) a dam engaging portion provided at the nip portion of a pair of ink rolls.

[Conventional technology]

The roll arrangement in the flexographic printing apparatus is shown in FIGS. 4 and 5. In the figure, 2 is an anilox roll, 3 is a rubber roll, 6a and 6b are ink dams, 14 is ink, and N is a roll nip portion.

6 and 7 are explanatory views of a conventional flexographic printing apparatus,
3 illustrates a method of supplying ink and a method of cleaning the ink.

An outline of the ink circulation device, which has been filed as a utility model application as Japanese Patent Application No. 63-50851, will be described below.

In this type of ink circulation device, (a) dams 6a and 6b are provided at the nipple portion N between the anilox roll 2 and the rubber roll 3, and ink is provided only inside the dam.
(B) Unnecessary excess ink between the dams 6a and 6b is collected by the collection pump 4. (c) The dams 6a and 6b move according to the printing width B of the corrugated cardboard to be printed. , (D) The outer regions of the dams 6a, 6b are lubricated with the lubricating liquid 15 on the surfaces of the anilox roll 2 and the rubber roll 3, and (e) The parts where the ink 14 and the lubricating liquid 15 are partitioned by the dams 6a, 6b are lubricated. Therefore, the dam 6 reciprocates constantly or intermittently. (F) When changing the ink, the dam 6 moves inward while collecting the ink 14 or the cleaning liquid 19 between the nips.

Hereinafter, the structure and function of this device will be described in detail.

As shown in FIGS. 6 and 7, the flexo ink 14a is supplied from the ink container 20a by the ink pump 21 through the supply pipe 22 to the nipple portion N formed by the anilox roll 2 and the rubber roll 3. The ink 14a supplied to the nip portion N is doctored by the rubber roll 3, is uniformly transferred to the surface of the anilox roll 2, and is further transferred from the surface of the anilox roll to printing on a printing cylinder (not shown). It should be noted that the corrugated cardboard sheet is adapted to be subjected to predetermined printing by contacting the printing plate.

During the printing operation, the ink 14a is constantly or intermittently supplied to the central portion of the nip portion N substantially in the roll axis direction, and the two dams 6a and 6b provided in the nip portion N are provided.
Stored in between.

The dams 6a and 6b can be moved in the roll axis direction according to the print width dimension B of the corrugated board sheet.

The ink 14a supplied to the nip portion N naturally flows from the central portion in the axial direction of the roll toward both dams 6a and 6b, and the excess ink is collected by the recovery pump 4 as shown in FIG. The ink is collected in the ink container 20a through the ink sucking nozzles 5a, 5b and the ink collecting pipes 23a, 23b provided in the.
On the other hand, the surfaces of the rubber roll 3 and the anilox roll 2 are in contact with each other with a predetermined pressure over the entire width in the axial direction, and rotate at their own surface speeds. By the way, dams 6a and 6a are used for the purpose of lubricating the roll surface and reducing wear.
Lubricating liquid 15 such as water is supplied to both outer sides of b, that is, a portion where the ink 14 does not flow, from the lubricating liquid supply ports 24a and 24b provided outside the dams 6a and 6b constantly or intermittently. The lubricating liquid 15 overflows from both ends of the nip portion N of the rubber roll 3 and the anilox roll 2, and the end pans 25a, 25
It flows down to b and is further discharged into the drainage groove 27 through the discharge pipes 26a and 26b. In this way, the inner surfaces of the dams 6a and 6b are lubricated by the ink 14a, and the outer surfaces of the dams are lubricated by the lubricating liquid 15 to lubricate the surfaces of the anilox roll 2 and the rubber roll 3, thereby improving the wear resistance.

As described above, the ink 14a is continuously or intermittently supplied into the dams 6a, 6b placed at the predetermined widthwise positions for printing, and the excess ink 14a is collected by the recovery pump 4 to remove excess ink 14a. Circulate to 20a. Ink 14a like this
It is possible to continuously print by circulating the.

Next, the ink exchange accompanying the order change will be described.

As shown in FIGS. 6 and 7, the ink exchange device of the flexographic printing machine is an ink supply for circulating ink between the ink containers 20a and 20b described above and an ink roll composed of a rubber roll 3 and an anilox roll 2. It is composed of a circulation device, a cleaning liquid supply device for supplying a cleaning liquid to the ink circulation path, and an exchange mechanism for operating the ink circulation supply device and the cleaning liquid supply device in a predetermined procedure.

As a procedure for ink replacement, first, the ink supply is stopped by stopping the ink pump 21, and a predetermined time is set by the timer setting, during which the ink 14 in the nip portion N between the rubber roll 3 and the anilox roll 2 is The ink container passes through the ink suction nozzles 5a, 5b of the dams 6a, 6b and the ink recovery pipes 23a, 23b by the suction pump 4 which continues to operate.
It is forcibly recovered to 20a. At this time, in order to further improve the ink recovery efficiency, the dams 6a and 6b move inward, respectively, and the ink of the Nip N is picked up by the dam 6 and sucked and recovered. Further, the ink in the ink supply pipe 22 and the pump 21 is allowed to spontaneously flow out within the set time of this timer and is similarly collected in the ink container 20a. Next, the lower end of the ink supply pipe 22 and the ink recovery pipe 23 is moved to a predetermined position on the bucket 30 by an ink recovery completion signal after a predetermined time of the timer, and then the solenoid valve 31 of the ink cleaning device is activated. The ink circulation supply path is cleaned by supplying the cleaning liquid 19. After the ink is collected, the dams 6a, 6b have moved to both end positions of the rolls, and when the cleaning liquid is collected, the dams 6a, 6b are moved inward while the cleaning liquid in the nip portion N is collected by the recovery pump 4 like the ink. . The cleaning liquid 19 collected by the collection pump 4 is forcibly discharged onto the bucket 30. Next, after a predetermined time, the supply of the cleaning liquid 19 is stopped by stopping the solenoid valve 31, and the predetermined time is set by the timer setting, and the cleaning liquid 19 in the ink supply pipe line 22 and the ink pump 21 is naturally discharged onto the bucket 30. Let it drain. Next, when the cleaning liquid recovery work end signal is received by the timer, the process proceeds to the return process, that is, the dams 6a, 6b that have been closer to the inside of the roll spread to the preset position (print width direction dimensional position) and stop. The lower ends of the ink supply pipe 22 and the ink recovery pipe 23 are connected to the connection ports 28b and 29b of the next-order ink container 20b by the exchange mechanism. When the ink pump 21 is started in this state, the next-order ink 14b is supplied again to the nipping portion N as described above, and the next printing is performed.

[Problems to be solved by the device]

As described in the section of the prior art, the ink dam that has been installed in the ink circulation device up to now has an ink width setting in the axial direction of the central portion, which is opposed to the ink dam, and a suction circuit for excessive excess ink or cleaning liquid. The main purpose of this is (a) ink leaks outward in the axial direction of the roll,
(B) There is a problem that the lubrication of the contact portion of the dam engaged with the ink roll is uncertain. In addition, excessive contact and uncertain lubrication of the dam that engages with the rubber roll will cause damage due to wear on the surface of the rubber roll,
This will significantly impair the doctoring and transfer functions of the ink.

As a countermeasure against these problems, there has been a method of providing an air nozzle formed substantially vertically toward the roll nip portion. However, structurally, (1) the inside of the air seal nozzle is clogged due to ink sticking, and the sealing effect is reduced.

(2) Ink may adhere to the outer peripheral surface of the roll in the seal portion, and the roll may be damaged (lubrication effect is small).

(3) When the air is blown vertically, the air flows into the ink suction nozzle located inside, and the recovery pump sucks the air and the ink suction action is reduced.

(4) If the air is blown vertically, the air blows out inside the dam and the accumulated ink is scattered to the outside.

There were problems, etc.

An object of the present invention is to provide an ink circulation device in a flexographic printing machine that solves these problems (defective points).

[Means for Solving the Problems]

The present invention provides an ink dam structure for controlling the ink supply width. (1) As shown in FIGS. 1 and 2, the tip of the ink sealing air nozzle is directed at a predetermined angle θ toward the outside of the opposing dam. And a predetermined amount of water (lubricant) is intermittently or continuously flowed into the air blowing port (air nozzle).

(2) As shown in FIG. 3, the tip of the blow-in port is inclined at a predetermined angle θ toward the outside of the opposing dam to allow air to flow in, and the supply holes (water (water () A nozzle for lubricating liquid) is provided to allow a predetermined amount of water (lubricating liquid) to flow in intermittently or continuously.

[Action]

The structure shown in FIG. 1, FIG. 2 and FIG.
Direct water (lubricant) to ink nozzle for ink seal
Water (lubricating liquid) into a nozzle (supply hole) provided in the vicinity of the ink seal air nozzle, whereby the ink is fixed in the ink seal air nozzle, or the seal is formed. There is no such problem as ink sticking to the outer peripheral surface of the roll at some portion and damaging the roll.

Also, by inclining the tip of the air nozzle to the outside of the dam, air flows into the ink suction nozzle inside the dam, or air is ejected inside the dam and the accumulated ink is scattered outside. The malfunction of the type ink lubricator is eliminated.

〔Example〕

In FIGS. 1 to 5, 2 is an anilox roll,
3 is a rubber roll, 4 is an ink recovery pump, 5 is an ink suction nozzle, 6 is an ink dam, 7 is an ink sealing air nozzle, 8 is air piping, 9 is pressure PA, 10 is a timer,
11 is a solenoid valve, 12 is a pipe for water passage, 13 is a pressure gauge PW, 14 is ink, 15 is water (lubricant), 16 is air, 17 is a flow control valve, 18 is a water nozzle, and B is on the seat. Printing width (distance between ink dams), PA is air pressure, PW is water pressure, θ is the tip inclination angle of the ink nozzle for ink sealing, and N is the nip portion of the ink roll.

The general structure of the flexographic printing apparatus, the supply of ink, and the method of cleaning the ink are the same as those described in the related art (FIGS. 6 and 7).

The ink dam 6 according to the present invention is supplied to the nip portion N via the ink supply pipe 22 (see FIG. 6) by moving relative to the printing width B of the traveling sheet 1 in the ink roll 2, 3 axis directions. It is possible to set the ink width in the roll axial direction of the ink to be used, and the ink suction nozzle 5 is provided for collecting excess ink, ink in the nipple portion N at the time of ink replacement, and the collected ink after cleaning via the recovery pump 4.

Hereinafter, the first to third embodiments of the present invention will be described with reference to FIGS.

In the first embodiment shown in FIG. 1, an ink seal air nozzle 7 is provided substantially in the center of an ink dam 6, and compressed air of a predetermined pressure is blown through an air pipe 8.

A water passage pipe 12 is connected in the middle of the air pipe 8 through an electromagnetic valve 11 which is operated by the control of a timer 10.

In the pair of ink dams 6a, 6b (see FIG. 4) provided opposite to each other, the ink sucking nozzles 5 provided inside each are the same as those of the conventional type.

Next, the operation will be described. The ink dam 6 is such that the air 16 having a predetermined pressure is continuously supplied from the normal air nozzle 7 to seal the gap between the ink rolls and the ink dams 6a and 6a arranged opposite to each other.
It functions to prevent the leakage (outflow) of the ink 14 supplied between b. The pressure PW of the water (lubricant) 15 is set to be slightly higher than the air pressure PA, and the solenoid valve 11
By the opening operation of the, the water 15 flows into the air pipe 8,
The air 16 and the air nozzle 7 flow out to the roll nip portion N. (The opening / closing operation time of the solenoid valve 11 can be arbitrarily variably set by the timer 10.) Due to the above-described function, there is a problem that ink adheres to the ink seal air nozzle 7 and the outer surfaces of the rolls 2 and 3 of the seal portion. It can be prevented.

The second embodiment shown in FIG. 2 is the solenoid valve of the first embodiment.
Instead of 11, water (lubricating liquid) 15 is configured to be continuously supplied into the air pipe 8, and the amount of water flowing into the ink seal air nozzle 7 is controlled via a flow rate adjusting valve 17. . The pressure PW of the water 15 is set to be slightly higher than the air pressure PA as in the first embodiment.

In the third embodiment shown in FIG. 3, water (lubricant) 15 is provided outside the ink dam 6 in the vicinity of the ink seal air nozzle 7.
Solenoid valve with dedicated nozzle 18 and operated by timer 10
Water 15 can be supplied intermittently via 11. The function of the ink suction nozzle 5 is the same as in the first and second embodiments.

In each of the above embodiments, the air nozzle 7 for ink seal
The tip of the ink is inclined to the outside of the dam at a predetermined angle θ with respect to the vertical line, functions to prevent the leakage of the ink 14, and the ink suction nozzle 5 located inside the dam 6
The inflow of air into the ink is prevented, and the action of the ink recovery pump 4 is ensured. In addition, due to the same structure, air is supplied to the inside of the dam 6.
Problems such as 16 jetting and scattering of the accumulated ink 14 are also solved.

Further, as a method of controlling the water (lubricating liquid) 15 in the third embodiment, if a flow rate adjusting valve 17 is provided in place of the solenoid valve 11, a predetermined amount of water can be continuously supplied.

[Effect of device]

The present invention relates to a pair of ink rolls that are horizontally supported adjacently to each other, a pair of ink dams that limit both ends of roll nip portions of these ink rolls, and an ink provided between these ink dams. In an ink supply device for a flexographic printing machine equipped with a supply pipe, an ink suction nozzle that opens inside the ink roll axial direction in the ink dam, and a predetermined slope outside the ink suction nozzle outside the axial direction of the ink roll. The following effects can be obtained by providing an air nozzle that opens with a groove and by allowing the lubricating liquid to flow into the air nozzle continuously or intermittently.

(1) Since the lubricating liquid is supplied to the air nozzle, clogging of the ink in the air nozzle can be prevented, and the reduction of the sealing effect can be eliminated (prevented).

(2) It is possible to prevent the ink from sticking to the outer peripheral surface of the roll of the seal portion, and solve the problem of damaging the roll.

(3) Since the direction of the ink seal air nozzles is inclined toward the outside of each dam, it is possible to prevent air from flowing into the ink suction nozzles located inside the dams, and thus the operation (efficiency) of the recovery pump. It can be improved.

(4) It is possible to prevent air from being blown out to the inside of the dam and prevent the problem that the ink accumulated in the roll nip portion is scattered to the outside.

[Brief description of drawings]

FIG. 1 is the first of the ink supply device of the flexographic printing machine of the present invention.
Roll axial sectional view of the ink dam portion in the embodiment,
FIG. 2 is a drawing similar to FIG. 1 in the second embodiment, and FIG.
The drawing is the same drawing as FIG. 1 in the third embodiment, FIG. 4 is an inclined view of an ink supply device in a general flexographic printing machine, and FIG. 5 is a sectional view taken along line YY of FIG. 4 and FIG. FIG. 7 is a side view of an ink supply portion of a conventional flexographic printing machine, and FIG. 7 is a perspective view of an ink and cleaning liquid circulation system in the conventional flexographic printing machine. 2 ... Anilox roll, 3 ... Rubber roll, 4 ... Ink collection pump, 5 ... Ink suction nozzle, 6 ... Ink dam, 12 ... Water supply piping, 14 ... Ink θ ... Air nozzle tip tilt angle N: Roll nip section

Claims (1)

[Scope of utility model registration request] 1. A pair of ink rolls that are horizontally supported adjacently to each other, a pair of ink dams that limit the ends of the roll nip portion of these ink rolls, and a pair of ink dams provided between these ink dams. In an ink supply device of a flexographic printing machine including an ink supply pipe, the ink dam, an ink suction nozzle opening to the inner side in the axial direction of the ink roll,
An air nozzle that opens outside the ink suction nozzle in the axial direction of the ink roll with a predetermined inclination is provided.
An ink supply device for a flexographic printing machine, characterized in that the lubricating liquid can be continuously or intermittently introduced into the air nozzle.