JP2002248737A - Method for changing ink of printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent mixing of a cleaning waste liquid with an ink when an ink color in a corrugated fiberboard printer is to be changed. SOLUTION: A method for changing the ink of the printer comprises the steps of recovering the ink of an ink reservoir 11 formed between a form roller 1 and a squeezing member 20 pressure contacted with the form roller, then cleaning the roll 1 with a cleaning liquid while rotating the roller 1, recovering the cleaning waste liquid stored in the reservoir 11, supplying the ink to a substantially central part of the reservoir 11 by an ink supply/recovery nozzle 4, pushing away an infinitesimal amount of the waste liquid of recovery leakage retaining at the bottom of the reservoir 11 by the ink flowing out from the nozzle 4 to the end of the reservoir 11, discharging the waste liquid by a waste liquid discharge means 80 at the end of the roller, and hence preventing mixing of the waste liquid of the leakage with the supplied ink as much as possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for changing ink in a printing machine for corrugated cardboard sheets.

[0002]

2. Description of the Related Art In a flexographic printing method for corrugated cardboard printing, the procedure of ink replacement is to recover old ink accumulated in an ink reservoir between an inking roll and a squeezing roll, then wash the roll, and wash waste liquid. After recovering the ink, a desired color ink is supplied to the ink storage unit.

[0003]

The washing waste liquid is collected in the ink storing section and is collected by suction from the nozzle.
The bottom of the ink reservoir formed between the rolls is narrowed in a wedge shape by the peripheral surface of the roll, and a small amount of waste liquid remains in the ink reservoir without being completely sucked up from the nozzle, and this waste liquid mixes with the next ink. There was a problem that the color of the ink was adversely affected. The present invention clarifies an ink replacement method that can solve the above problems.

[0004]

SUMMARY OF THE INVENTION The present invention relates to an ink reservoir (1) formed between an inking roll (1) having fine irregularities on its surface and a squeezing member (20) pressed against the inking roll. Ink is stored in 11) and the ink is transferred from the inking roll (1) to the printing plate attached to the plate cylinder (9) by the rotation of the inking roll (1). Then, after collecting the ink in the ink storage section (11), the ink is washed with the cleaning liquid while rotating the inking roll (1), and the cleaning waste liquid accumulated in the ink storage section (11) is recovered, and the ink supply and recovery is performed. Nozzle (4) with ink reservoir (11)
Supplies ink to the approximate center of the
By the ink flowing out of (4), a small amount of washing waste liquid collected and collected at the bottom of the ink storage section (11) is flushed to the end of the ink storage section (11), and the collected leakage waste liquid discharge means ( 80).

[0005]

[Operation and effect] The collected and washed waste liquid remaining in the ink storage section (11) is pushed by the ink and moves toward the end of the ink storage section (11). Since the waste liquid is discharged to the outside of the storage section (11), the waste liquid does not mix with the next ink, and even if mixed, the waste liquid is in a very small amount, and does not affect the color of the ink as visually noticeable.

[0006]

FIG. 1 shows a main part of a printing unit of a cardboard printing machine. The printing press feeds the cardboard sheets one by one to the printing unit.
(Not shown), a plurality of printing units corresponding to the number of printing colors, a punching device for punching a printed sheet in a box shape, and a ruler for forming ruled lines in accordance with a folding line.

The printing unit is provided with an inking roll (1) and a squeezing roll (2) so as to be able to come into contact with and separate from each other. A part (11) is formed. Inking roll (1)
A plate cylinder (9) is arranged in contact with the roll (1) below
A receiving roll (91) under the plate cylinder (9) facing the plate cylinder (9).
Is deployed. Ink is supplied to the ink storage section (11) from an ink supply / recovery nozzle (4) described later, and the liquid level is controlled to a set height by a liquid level sensor (not shown). As is well known, the inking roll (1) and the squeezing roll
(2) rotate in the direction of squeezing the ink in the ink reservoir (11), and the ink on the surface of the inking roll (1) is transferred to the printing plate on the plate cylinder (9) and received by the plate cylinder (9). Printing is performed on the cardboard sheet S supplied between the roll (91).

The inking roll (1) has fine irregularities formed on the surface of a hard roll such as a ceramic roll or a hard plating roll. The drawing roll (2) has a surface formed of rubber. Both rolls (1) and (2) have a length of 1.5 to 4.7 m depending on the size of the printing press. Both rolls (1)
Both ends of (2) are pressed against weir members (8) and (8) for closing the ends of the ink reservoir (11). The weir member (8) has an L-shaped discharge hole (81) opened on the side surface and the upper surface on the ink storage part (11) side. The discharge hole (81) of the weir member (8) is connected to a closed collecting can (50) described later by a suction collecting pipe (52).

The rolls (1) and (2) and the weir member (8) are covered by a cover.
It is covered by (6). As shown in FIG.
(6) is formed in a housing that accommodates both rolls (1) and (2),
In the ceiling plate (65), the running openings (61) of the nozzles (4), (5), (34), and (70) described later corresponding to the ink storage section (11) are connected to the ink storage section (11). The printing cylinder is opened at the corresponding position, and the lower surface is provided with an opening (62) for a printing cylinder intrusion through which a printing plate attached to the printing cylinder (9) comes into contact with the inking roll (1). The bottom plate (63) of the cover on the side of the squeezing roll (2) is bent obliquely upward toward the inking roll (1) beyond the ink reservoir (11), and the leading edge is extended over the entire length of the inking roll (1). Closing plate approaching
(63a).

A squeezing roll for the upper opening (34) of the cover (6)
The opening edge (34a) on the (2) side is close to the squeezing roll (2) at a position almost directly above the axis of the squeezing roll (2). Therefore, the inside of the cover (6) is drawn by the drawing roll on the drawing roll (2) side.
A mist chamber (60) having narrow slits (66) and (67) opened with respect to (2) and the inking roll (1).

In the mist chamber (60), one or a plurality of fine spray nozzles (21) are provided. The fine spray nozzle (21)
This is for actively wetting the surface of the squeezing roll (2) by spraying the thinning liquid in the form of fine mist to maintain the mist chamber (60) at a high humidity near saturation. The fine fog has a particle size of 50 μm or less, preferably 30 μm or less. In the embodiment, a pair of fine mist spray nozzles (21) and (21) are provided at a small interval in the longitudinal direction of the roll under the central portion side of the squeezing roll (2), and the spray-side tips are rolled to each other. It is in a slightly diagonally upward position toward the far end. A humidity sensor (68) is installed in the mist chamber (60),
Spraying and stopping of spraying are controlled by the sensor, and the mist chamber (60) is maintained in a saturated state or a high humidity close to the saturated state.

A closed box (3) is slidably provided along the axis of the squeezing roll (2) above the squeezing roll (2) with the ceiling plate (65) of the cover (6) interposed therebetween. As will be described later, the closed box (3) is a main component for ink supply and recovery, and also serves to support and move the ink supply / recovery nozzle (4) and the washing waste liquid recovery nozzle (5). And is connected to a slide drive device (not shown). The slide drive device can be switched between at least two modes: an ink recovery / washing liquid recovery mode and an ink circulation mode.

In the ink collecting / washing liquid collecting mode, the closed box (3) is reciprocated one or more times over the entire length of the ink storing section (11). The ink circulation mode is a mode during a printing operation, and as shown in FIG.
The closed box (3) that was waiting at the center of 1) is
As shown in (1), the ink storage unit (11) is moved to one end, and is slid from the moved position toward the center of the ink storage unit (11) by a predetermined section, for example, 50 cm. Next, as shown in FIG. 3C,
The closed box (3) is moved to the other end of the ink reservoir (11), and is slid from the moved position toward the center of the ink reservoir (11) for a predetermined section. Next, the closed box (3) is moved to a position distant from the slide section, in this embodiment, to the center of the ink storing section (11), and temporarily stopped here. This cycle is repeated during the printing operation. At the end of the above-mentioned two operation modes, the closed box (3) stands by at the center in the longitudinal direction of the ink storing section (11).

The closed box (3) accommodates an ink tank (31) so that it can be taken out, and the outside can be moved up and down a nozzle mounting plate (33) by connecting it to a lifting drive (32) such as a cylinder device. Have. The nozzle mounting plate (33) is located horizontally above the ink reservoir (11) along the length direction of the ink reservoir (11), and has two ink supply / recovery nozzles (4) at both ends. ), (4), two cleaning waste liquid collecting nozzles (5), (5) are provided inside thereof in a downward direction. The horizontal distance between the two ink supply / recovery nozzles (4) (4) depends on the size of the printing press,
It is appropriate to set the size to 20 to 60 cm depending on the size of the closed box (3) depending on the size of the ink tank (31).

The lower ends of the ink supply / recovery nozzle (4) and the waste liquid recovery nozzle (5) are obliquely cut on the side of both rolls (1) and (2) corresponding to the bottom shape of the ink reservoir (11). Being sharp. Ink supply / recovery nozzle (4) and waste liquid recovery nozzle
The height position of the lower end of (5) is aligned, and the lifting drive
The nozzle mounting plate (33) can be switched between a two-stage position of an ascending position and a descending position with the lower end of the nozzle (4) (5) at the ascending position. The lower end of the nozzles (4) and (5) at the lower position is slightly lower than the set height of the surface, and the lowermost part of the ink reservoir (11) is barely bitten between the rolls (1) and (2). Invade.

A pipe (4a) through which a closed box (3) is hermetically and detachably penetrated through the ink supply / recovery nozzle (4).
Is connected, and the tip of the pipe (4a) is connected to the ink tank (31).
I am immersed in. The length from the tip of the ink supply / recovery nozzle (4) to the tip of the pipe (4a) in the ink tank (31) is
It can be suppressed to about 1.2 m. Closed box (3)
Is connected to a suction pipe for pressure reduction (35) and an air supply pipe for pressurization (36).
The pressure inside the closed box (3) is increased by pumping the pressurized air into the ink tank (31), and the ink in the ink tank (31) is pushed out to supply the ink from the ink supply / recovery nozzle (4) to the ink reservoir (11). . The air in the closed box (3) is sucked by the depressurizing suction pipe (35), and the inside of the closed box (3) is depressurized. The ink of 11) can be sucked and collected in the ink tank (31). In the drawing, the suction box (35) for decompression and the air supply pipe (36) for pressurization are separately connected to the closed box (3), but suction and pressurization can be performed by a common pipe.

The waste liquid recovery nozzle (5) is connected to a suction recovery pipe (51) and to a closed recovery can (50). A vacuum suction pipe (53) is connected to the closed collection can (50), and the air inside the closed collection can (50) is suctioned by the suction pipe for vacuum (53) so that the inside of the closed collection can (50) is removed. After the ink reservoir (11) has been washed through the discharge hole (81) of the weir member (8) through the suction recovery pipe (51), the waste liquid recovery nozzle (5), and the recovery pipe (52). Waste liquid can be collected by suction.

In the closed box (3), the nozzle (4)
In addition to (5), two cleaning liquid supply nozzles (34) and (34) and a thinning liquid supply nozzle (70) are provided. Further, thinning liquid supply nozzles (7) and (7) are provided at fixed positions which do not collide with the closed box (3) at both ends of the ink storage section (11).

The cleaning liquid supply nozzles (34) and (34) are located above the inking roll (1) and closer to the squeezing roll (2). It is connected to a cleaning liquid supply device (not shown) for spraying a fixed amount of cleaning liquid by spraying or dropping. Thinning liquid supply nozzle (7) (7)
(70) is connected to a thinning liquid supply device (not shown),
The thinning liquid supply device continuously feeds the thinning liquid to the ink storage section (1).
Depending on the amount of ink used and the amount of ink supplied, the ink in the ink storage section (11) may become too thin, such as dropping it in 1) or supplying a certain amount of thinning liquid to the ink storage section (11) at regular intervals. The diluting liquid is supplied to the storage part (11) within a range not present.

The washing liquid, the thinning liquid, and the thinning liquid sprayed from the fine mist injection nozzles (21) and (21) are tap water in the embodiment. However, an additive may be added to the tap water, or other than tap water. However, it is also possible to adopt a liquid corresponding to the characteristics of the ink.

However, in order to supply the ink to the empty ink reservoir (11), the ink supply / removal on the closed box (3) is performed while sliding the closed box (3) along the ink reservoir (11). The ink is supplied from the recovery nozzle (4). At this time, the inking rolls (1) and (2) are rotated to prevent the lines of the ink surface from adhering to the rolls (1) and (2), and to stimulate the ink to obtain a stirring effect. The ink supply / recovery nozzle (4) is in the up position, but if some amount of ink is collected, the tip of the ink supply / recovery nozzle (4) is immersed in the ink surface, and is immersed together with the closed box (3). Since the ink is laterally moved, the ink is agitated, and the viscosity of the ink is prevented from increasing.

During the ink supply and printing operation, the thinning liquid is ejected from the fine spray nozzles (21) and (21) to squeeze the roll (2).
The surface is covered with fine particles of the diluting liquid to actively wet (wet), and the mist chamber (60) is filled with fine mist. Since the mist chamber (60) is maintained at a high humidity close to saturation with fine fog, when the squeezing roll (2) rotates, fine particles of the thinning liquid covering the roll surface continue to the ink reservoir (11). Be brought in. When an ink thinner such as water is dropped directly into the ink storage section (11), the thinner does not immediately adapt to the ink and is difficult to mix due to differences in the specific gravity, viscosity, etc. of the thinner and the ink. (2) The surface of the squeezing roll (2) is wetted from the ink storage unit (11) by diluting the peripheral surface into a thin film with liquid fine particles and bringing the wetting into the ink storage unit (11) by rotating the roll. ) And blends well with the ink of (1) and does not cause unevenness in the viscosity of the ink.

As shown in the embodiment, the fine mist spray nozzles (21) and (21) are slightly inclined to the roll side under the squeezing roll (2), so that the squeezing roll (2) is more positively arranged. Has the effect of wetting the surface.

Further, since the fine mist escaping from the outlet (66) above the squeezing roll (2) of the mist chamber (60) creates a high humidity atmosphere in the vicinity of the ink storage section (11), the moisture in the ink storage section (11) is reduced. Evaporation is suppressed to prevent viscosity increase of ink.

If ink is supplied up to the set liquid level,
The ink supply is stopped by the function of the liquid level sensor, and the closed box (3) temporarily returns to the center of the ink storing section (11) (FIG. 3A). When the printing operation is started by rotating the inking rolls (1) and (2), the closed box (3) moves to one end of the ink reservoir (11). Therefore, the ink supply / recovery nozzle (4) on the closed box (3) also moves to one end of the ink storage section (11) while the tip is immersed in the ink. The ink supply / recovery nozzle (4) sucks and recovers the ink in the ink reservoir (11) while moving a predetermined distance from the movement position to the center side of the ink reservoir (11), for example, about 50 cm (FIG. 3B). . Ink supply
When the collecting nozzle (4) sucks and collects ink in the collecting section at the end of the ink storing section (11), the ink level moves down from the center of the ink storing section (11) to the collecting section. Then, a flow of ink occurs.

Next, the suction and recovery of the ink is stopped, and while the tip of the ink supply / recovery nozzle (4) is immersed in the ink, the closed box (3) is moved to the end opposite to the ink reservoir (11). Move. While sucking and collecting ink from the moving position by the ink supply / collection nozzle (4) in the same section as above,
The closed box (3) and the ink supply / recovery nozzle (4) are moved. In the same manner as described above, the ink level moves down from the center of the ink storage section (11) by lowering the liquid level in the collection section, and the ink flows in the ink storage section (11).

Next, with the ink suction and collection stopped,
The closed box (3) is moved to a position away from the suction / recovery position, and in the embodiment, is returned to the center of the ink reservoir (11), and the ink supply / recovery nozzle (4) is moved to the ink reservoir at that position.
Supply ink to (11). With the liquid level sensor, the liquid level does not exceed the set height. During the printing operation, the above cycle is repeated, and the ink reservoir (11) and the ink tank (31)
Circulate ink between and. Also, during the printing operation, an appropriate amount of the thinning liquid is supplied from the thinning liquid supply nozzles (7) at both ends of the ink storage section (11) and the thinning liquid supply nozzle (70) on the closed box (3). .

As described above, during the printing operation, the ink storage section
Suction and recovery of ink at both ends of (11) and the ink storage section (1
1) The ink supply at the center is repeated, and the movement of the ink supply / recovery nozzle (4) is performed while the tip of the nozzle is immersed in the ink, so that the ink reservoir (11) constantly generates ink flow, Stir the ink. Thinning liquid supply nozzle (7)
(7) Although the viscosity of the ink is reduced in the portion where the thinning liquid is supplied in (70), the flow of ink caused by ink suction and recovery in the predetermined section of the ink supply / recovery nozzle (4) is described.
Ink supply / recovery nozzle immersed in ink (4)
The ink is replenished in accordance with the lateral movement of the ink, the amount of ink collected for printing, and the amount of ink used for printing, thereby preventing the increase in the viscosity of the ink and the unevenness in the viscosity of the ink.

In particular, as in the embodiment, the thinning liquid supply nozzle
(7) An ink supply / recovery nozzle (4) collects the portion of the ink whose viscosity has been temporarily reduced by the supply of the diluting liquid from (7) into the ink tank (31), thereby providing an ink tank.
The effect of adjusting the ink viscosity in (31) is obtained.

In order to carry out the ink change, the rotation of the rolls (1) and (2) is stopped, and the ink is
The collection nozzle (4) and the waste liquid collection nozzle (5) are connected to the ink storage section.
Lower to the deepest position of (11). The reason why the rotation of the rolls (1) and (2) is stopped is to prevent the nozzles (4) and (5) from being caught between the rolls.

While the closed box (3) is slid, the ink in the ink reservoir (11) is sucked and collected by the ink supply / recovery nozzle (4) on the box (FIG. 4A). In the case of a method of sucking and collecting ink by vacuum pressure as in the embodiment, the ink supply / recovery nozzle (4) is connected to the ink storage section (11).
Reciprocating once or twice over the entire length of the ink reservoir (1
Most of the ink in 1) can be collected by suction. When replacing ink, replace the ink supply / recovery nozzle (4), pipe (4a) and ink tank (31) as one set. It is a small amount of ink that has not been sucked and collected in the ink storage section (11) and remains in the ink storage section (11). It does not cause a large amount of ink loss.

With the ink supply / recovery nozzle (4) and the waste liquid recovery nozzle (5) raised, the rolls (1) and (2) are rotated, and in this state, the cleaning liquid is supplied while the closed box (3) is slid. Roll (1) for applying the cleaning liquid from the nozzle (34)
(FIG. 4B). Almost all of the ink adhering to the inking roll (1) in the form of a thin film is washed away, and the washing waste liquid accumulates in the ink reservoir (11). Since the amount of the ink adhering to the inking roll (1) in the form of a thin film is very small and the ink is water-based, the amount of the cleaning liquid required for cleaning is small.

The rotation of the rolls (1) and (2) is stopped, and the ink supply / recovery nozzle (4) and the waste liquid recovery nozzle (5) are lowered to the deepest position of the ink reservoir (11), and sealed in this state. While sliding the box (3), the waste liquid is sucked and collected by the waste liquid collecting nozzle (5) into the closed collecting can (50). Sealed collection cans
When the suction of (50) works, suction force also acts on the discharge holes (81) of the weir members (8) at both ends of the ink reservoir (11), and the weir members (8)
The washing waste liquid is collected in the closed collecting can (50) (see FIG. 4).
C).

In the case of a system in which the cleaning waste liquid is suctioned and recovered by vacuum pressure as in the embodiment, if the waste liquid recovery nozzle (5) is reciprocated once or twice over the entire length of the ink storage section (11), Most of the washing waste liquid in the ink storage section (11) can be collected by suction.

As described above, the ink can be recovered with little loss at the time of ink replacement, and a small amount of washing water is required for washing the rolls, and the concentration of the washing waste liquid is low. Therefore, large-scale equipment is not required, and running costs for waste liquid treatment can be suppressed.

Next, the ink supply / recovery nozzle (4) and the waste liquid recovery nozzle (5) are raised, and while the rolls (1) and (2) are rotated, the length of the ink storage section (11) in the longitudinal direction is increased. Ink supply / recovery nozzle on closed box (3) waiting in the center
Supply ink from (4). In this case, the ink supply / recovery nozzle (4) is not moved laterally, but remains at the standby position.
In addition, the suction of the closed collection can (50) is made effective.

The ink flowing out of the nozzle (4) flows to the dam member (8) through the bottom of the ink storing section (11). A small amount of washing waste liquid that could not be recovered by the waste liquid recovery nozzle (5) is stored at the bottom of the ink storage unit (11) that narrowed in a wedge shape.
By the flow of the ink toward the weir member (8), the residual waste liquid is pushed away by the ink (FIG. 5A). The momentum of the ink flow,
Due to the difference in properties such as the specific gravity and viscosity between the waste liquid and the ink, the waste liquid is flushed to the weir member (8) without being mixed with the ink. As shown in FIG. 5B, both ink and waste liquid are weir members.
The liquid level rises together with approaching (8).

Since the suction force of the closed collecting can (50) acts on the discharge hole (81) of the weir member (8), the discharge hole of the weir member (8) is used.
The waste liquid pushed out to (81) is sucked and collected in the closed collecting can (50). As described above, the waste liquid is flushed toward the weir member (8), so that the liquid level of the waste liquid gradually increases, and the discharge hole (8
Since the opening on the side of the ink storage section (11) of 1) is closed by the liquid surface, the entrapment of air from the discharge hole (81) is suppressed, and the waste liquid can be sucked and collected with a strong suction force.

At a timing immediately before the ink is collected in the closed collecting can (50) from the discharge hole (81), the suction of the closed collecting can (50) is released. This is done by measuring the time required for the ink supplied to the center of the ink storage section (11) to flow to the end of the ink storage section (11) and setting it by a timer, or by setting the waste liquid and the liquid quality of the ink. This can be realized by disposing a liquid quality detector for detecting a difference at the end of the ink storage section (11). As described above, almost all the washing waste liquid can be recovered. Ink reservoir (1
Even if a thin film of waste liquid remaining on the wall surface in 1) or a small amount of waste liquid that could not be collected is mixed with newly supplied ink, it does not affect the color of the ink. In the embodiment, the ink supply is performed by two ink supply / recovery nozzles (4).
Since this is performed by (4), the residual waste liquid in a narrow area between the nozzles (4) and (4) is mixed with the ink, but the amount of this waste liquid is negligible, and the color of the ink Has no effect.

In the above-described embodiment, the collected leaked waste liquid is
It was recovered through the recovery pipe (52) from the discharge hole (81) of (8),
The collecting leakage waste liquid discharging means (80) is not limited to this, and the dam member (8) is separated from the end faces of the rolls (1) and (2) by raising or moving the dam member (8) outward. Then, the waste liquid can be drained and collected from the end of the ink storage section (11).

In the above embodiment, the surface of the squeezing roll (2) is wetted with fine fog and brought indirectly into the ink storing section (11), and the ink is supplied to the thinning liquid supply nozzles (7), (7) and (70). Reservoir (1
Although the direct bringing in of the diluting liquid is also used in 1), it is also possible to omit one of the direct carrying and the indirect carrying.

In the above-described embodiment, in the ink circulation cycle shown in FIG. 3 during the ink recovery and the ink supply during the printing operation, the ink supply / recovery nozzle (4) uses the ink storage unit.
The ink was collected while running the end of (11) for a predetermined section. However, the number of ink supply / recovery nozzles (4) was increased and the ink was collected and arranged in the longitudinal direction of the ink storage section (11) Are arranged at intervals in the long direction of the ink storage section (11).
The ink supply / recovery nozzle (4) can be sucked and recovered in a stopped state at the end of the inking roll (1) using the book nozzles (4) (4) alone, etc., and ink circulation is possible. In the suction and recovery of the ink in the cycle, it is not always necessary to run the ink supply / recovery nozzle (4) in a certain section.

In the above embodiment, the inking roll
(1) Squeezing roll as squeezing member (20) for squeezing ink on
(2) was used, but the present invention is not limited to this. As shown in FIG. 6, the band-shaped plate (22) was brought into pressure contact with the inking roll (1) over the entire length of the roll. An ink reservoir (11) can be formed between them. In the case of FIG. 6, the band-like plate (22) is oriented in a direction opposite to the rotation of the inking roll (1), and the block (23) supporting the band-like plate (22) is formed by the inking roll of the ink storing section (11). The wall of the opposite side of (1) is constituted, and the band-like plate (22) also serves as the bottom of the ink reservoir. The embodiment of FIG. 6 can also achieve the same effect as described above except that the mist chamber is filled with fine fog and the surface of the squeezing roll (2) is wetted.

In the above embodiment, supply and recovery of ink to and from the ink storage section (11) are performed by pressurizing and depressurizing the closed box (3), and recovery of washing waste liquid is performed by depressurizing the closed collecting can (50). However, it is also possible to use a tube pump. The tube pump is a known pump that presses the flexible tube intermittently by rubbing the flexible tube with a roller in the longitudinal direction, and conveys the fluid in the tube in the direction in which the roller is pushed out. The transport performance of the tube pump is inferior to that of the embodiment.

The present invention can be applied not only to aqueous inks, but also to glycol-based inks having a low viscosity and a good drying speed. Various changes are possible within the scope of the claims.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a printing unit.

FIG. 2 is a sectional view of the same.

FIG. 3 is an explanatory diagram of movement of an ink supply / recovery nozzle during a printing operation.

FIG. 4 is an explanatory view of the movement of a waste liquid collecting nozzle at the time of cleaning waste liquid collection.

FIG. 5 is an explanatory diagram in which the supplied ink pushes away the washing waste liquid.

FIG. 6 is a sectional view of another embodiment of the squeezing member for the inking roll.

[Explanation of symbols]

 (1) Ink roll (11) Ink reservoir (2) Squeeze roll (3) Closed box (4) Ink supply / recovery nozzle (5) Waste liquid recovery nozzle (6) Cover (60) Mist chamber (7) Thinner Supply nozzle (70) Thinner supply nozzle (8) Weir member

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B41F 35/04 B41F 31/02 B

Claims (5)

[Claims] 1. An ink reservoir (11) formed between an inking roll (1) having fine irregularities on its surface and a squeezing member (20) pressed against and in contact with the inking roll. A method of transferring ink from an inking roll (1) to a printing plate attached to a plate cylinder (9) by rotation of an inking roll (1), comprising: After the ink of (11) is collected, the ink is washed with the washing liquid while rotating the inking roll (1), and the washing waste liquid accumulated in the ink storage section (11) is collected, and the ink is supplied.
The recovery nozzle (4) supplies ink to the approximate center of the ink storage unit (11), and the ink flowing out of the ink supply / recovery nozzle (4) causes recovery leakage remaining at the bottom of the ink storage unit (11). A small amount of washing waste liquid is flushed to the end of the ink storage section (11) and discharged by the collecting waste liquid discharging means (80) at the end of the roll to minimize mixing of the collected washing liquid waste and supply ink. Printing machine ink change method. 2. The method according to claim 1, wherein the squeezing member (20) is a roll (2). 3. The method according to claim 1, wherein the squeezing member (20) is a strip (22). 4. A collection leakage waste liquid discharging means (80) is provided in an ink storage section (1) in a weir member (8) provided at an end of the ink storage section (11).
A discharge hole (81) communicating with (1) is opened, and a suction / recovery pipe (5
4. The method according to claim 1, wherein the method (2) is connected. 5. A collection leakage waste liquid discharging means (80) for moving a weir member (8) provided at an end of an ink storage section (11) to open an end of the ink storage section (11). 4. A method for changing ink in a printing press according to claim 1.