JP2000202994A - Ink supply control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink supply control method by which the results of changing a print density during operation of a printing press are rapidly reflected in an actual printing operation. SOLUTION: An ink film thickness is increased by setting the opening of an ink key 14 larger and an ink fountain roller 2 is made to revolve rapidly so that the revolution reaches a velocity V2 during a section from the lower end gap part (position A) of the ink key 14 to a part (position B) which comes into contact with an ink ducting roller 5. That is, the tip (position C) of an already adjusted ink film is made to rapidly move to the position B by increasing or reducing the revolutional velocity of the ink fountain roller 2 in such a state that the ink fountain roller 2 is separated from the ink ducting roller 5. In addition, under such a state that the ink fountain roller 2 is in contact with the ink ducting roller 5 (positions following the position B), the ink fountain roller 2 is made to revolve at the same velocity V1 as a conventional set velocity corresponding to the velocity of a printing press.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink supply control method applied to, for example, an ink supply section of a sheet-fed printing press.

[0002]

2. Description of the Related Art As shown in FIG. 6, a sheet-fed printing press includes an ink reservoir 1, an ink source roller 2 forming one side surface of the ink reservoir 1, an ink feeding roller 5, a transfer roller 6, and various ink rollers. Group 7, inking roller 8, printing plate 10
Cylinder 9, blanket cylinder 12, dampening water device 1
5 and a control device 3 for appropriately controlling the unit group. The ink reservoir 1 includes an ink source roller 2, left and right side walls 16a and 16b, a bottom plate, and the like. The bottom plate has a plurality of plates called ink keys arranged side by side along the axial direction of the ink source roller 2. The ink keys 14a, 14b... (Hereinafter abbreviated as 14) are fulcrum shafts 1 at the rear end (left side in the figure).
7 are supported so as to be able to swing around the center, respectively, and are independently swung up and down by a swing driving device 18. Therefore, if the gap S between the lower end of each ink key 14 and the outer peripheral surface of the ink source roller 2 is adjusted for each ink key 14, the thickness of the ink film that is rotated and transferred via the ink source roller 2 can be reduced. In the axial direction. On the other hand, as shown in the drawing, the drive system of the ink source roller 2 includes a rotating body 19 and a shaft 2 configured to be continuously rotated by the machine (printing machine main body).
0, a link 21, a support shaft 22, and a latch (claw, ratchet) device (not shown) provided on the shaft of the ink source roller 2. When the rotating body 19 continuously rotates in the direction of the arrow J, the link 21 swings in a plane parallel to the paper surface via the shaft 20, and when the link 21 swings in one direction (when swinging rightward in the drawing). ), The latch device is activated, and the latch device does not operate (idle) during the reverse swing (when swinging leftward in the drawing). By such an operation, the ink source roller 2 performs an intermittent motion. That is, the ink source roller 2 moves the arrow K only when the link 21 swings in one direction (to the right in the drawing).
Rotate in the direction of. The rotation angle can be changed by adjusting a rotation radius R, which is a distance from a rotation center point of the ink source roller 2 of a latch (not shown) pivotally supported by the link 21. Under such a configuration, the ink feeding roller 5
Contacts at a predetermined timing corresponding to the rotation of the intermittently rotating ink source roller 2 to receive the ink 11 and transfer it to the transfer roller 6 on the downstream side. The ink supply amount is appropriately set according to the magnitude of the rotation amount (angle) of the ink source roller 2 and the gap S, that is, the opening of the ink key 14.

When printing is started, the image rate of the printing plate 10 to be provided for the next order is measured, and based on the image rate data, the opening degree of each ink key 14 in the ink reservoir 1 and the opening degree of the ink source roller 2 are determined. Set the amount of rotation (angle) for each operation. That is, the image ratio is input to the control device 3 as data, and the control device 3 performs a predetermined process for controlling the drive system and performs a predetermined setting. Under such a setting, the ink 11 filled in the ink reservoir 1 is rotated and transported through the gap S while adhering to the outer peripheral surface of the ink source roller 2, and is passed through the ink feeding roller 5 which swings and separates. Is transferred to the transfer roller 6. Subsequently, the ink 11 is appropriately kneaded during the transfer to the ink roller group 7, and is supplied from the ink forming roller 8 to the printing plate 10 wound around the plate cylinder 9. The image is transferred to the blanket cylinder 12 via the printing plate 10 as a picture. Then, the image is transferred onto the sheet 13 running while contacting the blanket cylinder 12, and printing of a predetermined color is completed.

[0004]

Next, problems of the ink supply device will be described with reference to FIGS. 7 and 8. FIG. In a printing machine, for example, when increasing the print density, that is, when increasing the amount of ink to be transferred and supplied via the ink source roller 2, the opening of the ink key 14 is adjusted as shown in FIG. With this setting, when the ink key 14 is opened in the gap S2 (gap S2) from the initial state (gap S1) shown in FIG. 8A (gap S2), as shown in FIG. The thickness of the ink film adhering to the surface gradually increases during operation of the ink key 14 with the rotation. Then, (c) of FIG.
When the state shown in (1) is reached, the ink supply amount to the ink feeding roller 5 becomes stable as the ink film thickness set for the first time. That is, the effect appears for the first time in FIG. In the drawings, the lead lines of the gaps S1 and S2 are
Although it is oblique due to the layout, the gap means the shortest distance. Therefore, even if the thickness of the ink film to be transferred to the outer peripheral surface of the ink source roller 2 is changed at the position A (see FIG. 7) depending on the opening degree of the ink key 14, the effect is not changed at the position B (see FIG. 7). It takes time to affect the ink feeding roller 5 during printing, and during that time, the printing surface density of the printed sheet 13 (see FIG. 6) becomes unstable, and waste paper increases. As an example, such a waste sheet is considered in consideration of the response of the ink roller group.
It takes about 70 to 100 sheets to complete the change. Today, there is a printing machine that employs a type in which the ink source roller 2 is continuously rotated.
Is controlled in conjunction with the machine speed, the speed is slow, and a large amount of waste paper is generated in the same manner as described above due to the problem of responsiveness.

As shown in FIGS. 9 and 11, the ink supply amount is the rotation amount (angle) of the ink source roller 2 even when the opening degree of the ink key 14, that is, the gap S is fixed.
Can be controlled to some extent arbitrarily. Hereinafter, a specific description will be given. The ink transfer amount is
From the state shown in FIG. 9 in which the ink feeding roller 5 is in contact with the ink source roller 2, it can be controlled by the rotation angle θ of the ink source roller 2 which rotates further as shown in FIG. 11A or 11B. If the rotation angle θ of the ink source roller 2 rotating from the contact of the ink feeding roller 5 to the separation thereof is adjusted to be small as shown in FIG. 11A (θ = θ
1) The ink supply amount can be reduced, and if the ink supply amount is largely adjusted as shown in FIG. 3B (θ = θ2), the ink supply amount can be increased. Note that the alternate long and short dash lines in FIGS. 7A and 7B indicate the amount of ink transferred to the ink feeding roller 5 side.

At the lower end of the ink key 14, an ink flow force is generated with the rotation of the ink source roller 2, and the ink key 14 and the ink source roller 2 exert an action force F (FIG. 9).
See). The ink flow force changes with a change in the rotation angle and the machine speed of the ink source roller 2 and a change in the gap S, and increases as the peripheral speed of the ink source roller 2 increases, and the gap S decreases. It increases indeed. Therefore, as another problem, as shown in FIG. 10, this action force causes the ink key 14 and the ink source roller 2 to bend, and the thickness of the ink film on the ink source roller 2 varies. That is, the film thickness (gap S) at the center in the axial direction of the ink source roller 2 is set at both ends (gap S0, S0 <S).
The gap tends to become thicker, and the smaller the gap S, the larger the gap. For this reason, there is a problem that the ink density on the printing surface fluctuates in the width direction of the sheet, thereby deteriorating the product quality. Further, even when the ink key opening degree is the same, if the peripheral speed of the ink source roller 2 is different, there is a problem that the density of the entire printed matter varies.

The present invention has been made in view of such circumstances, and has as its object to provide an ink supply control method in which a result of a print density changed while a printing press is operating appears quickly.

[0008]

SUMMARY OF THE INVENTION An ink supply control method according to the present invention has been made in order to solve such a problem, and has been applied to an ink source roller, left and right side walls, a plurality of ink keys forming a bottom, and the like. Ink supply for controlling the amount of ink supplied to the ink feed roller which comes into contact with and separates from the ink source roller by adjusting the gap between the lower end of the ink key and the outer peripheral surface of the ink source roller and the amount of rotation (angle) of the ink source roller. In the apparatus, the rotary drive system of the known ink source roller is separated and independent from the drive device of the printing press main body, and is configured to be rotatable independently via a motor that can be arbitrarily increased and reduced. At a timing during which the ink source roller is separated from the ink source roller, the ink source roller is rotated at a high speed, and the gap adjusted above is adjusted. · The film was to be controlled to quickly move the ink transfer point of the ink ductor roller.

While the ink key is not adjusted, the rotation of the ink source roller may be rotated at a set speed following the machine speed, and the above control may be performed only during the adjustment of the ink key.

In the above configuration, when the ink feeding roller is in contact with the ink source roller, the ink feeding roller is rotated at a predetermined rotation speed that follows the machine speed, and the ink feeding roller is moved away from the ink source roller at a timing. After rotating the ink source roller at a constant speed and at a constant angle (that is, at least the angle at which the ink feeding roller contacts and rotates with the ink source roller), an ink film is formed on the outer peripheral surface of the ink source roller. Rotate the ink supply roller at high speed until the tip of the ink film formed on the outer surface of the supply roller reaches the position where the ink supply roller comes in contact with and separates from the ink supply roller. The operation of the roller may be controlled at a set speed that follows the machine speed.

According to the present invention, the rotational speed of the ink supply roller is set to a constant speed irrespective of the machine speed, and the length of time of the swinging of the ink supply roller contacting the ink supply roller is controlled so as to be proportional to the machine speed. Including.

[0012]

Next, an embodiment of an ink supply control method according to the present invention will be described with reference to the drawings.
FIG. 1 shows an overall schematic configuration of an ink supply device according to a first embodiment to which the ink supply control method of the present invention is applied. As shown in FIG.
The ink 11 is transferred and supplied to the printing plate 10 wound around the plate cylinder 9 via the ink feeding roller 5, the transfer roller 6, the ink roller group 7, and the ink forming roller 8, and further transferred to the blanket cylinder 12. A predetermined printing is performed on the sheet 13 traveling while contacting the blanket cylinder 12. In addition,
Such a series of functions are the same as those of the conventional technology, and therefore, detailed description thereof is omitted. In this apparatus, as shown in the figure, the rotation drive system of the ink source roller 2 forming one side surface of the ink reservoir 1 is separated and independent from the drive device of the printing press main body. That is, it is configured to be rotatable by the motor 4 which can be independently and arbitrarily increased / decreased via the control device 3. It should be noted that the motor referred to here may be of a type that is generally used independently and arbitrarily to accelerate and decelerate.

Next, the control by the control device 3 will be described with reference to FIG.
This will be described with reference to FIGS. When the printing density is increased during operation of the printing press, for example, the opening degree of the ink key 14 is adjusted (enlarged) to increase the amount of ink to be transferred and supplied via the ink source roller 2, and the gap S (see FIG. 1)). Thereafter, as shown in FIG. 2, the ink source roller 2 is accelerated to the speed V2 in a section from the lower end gap portion (position A) of the ink key 14 to a portion (position B) in contact with the ink feeding roller 5. Rotate (high speed). Then, after the position B, the motor is decelerated (low-speed) so as to be at the same speed V1 (V1 <V2) as the conventional set speed corresponding to the machine speed. The rotational speed of the machine is detected and confirmed by, for example, an encoder or the like.
Is set so that the ink feeding roller 5 does not come into contact with the ink source roller 2 at the time of high-speed rotation.

For example, control is performed at a timing as shown in FIG. In the figure, two different time charts are shown. In FIG. 7A, the speed of the ink source roller 2 is controlled at the following timing. When the ink supply roller 5 is rotating at the speed V1 while being in contact with the ink supply roller 5, the ink supply roller 5 is accelerated as soon as the ink supply roller 5 is separated from the ink supply roller 2, and the ink supply roller 2 is rotated at the speed V2. . Before the acceleration (during the operation at the speed V1), the ink key 14 is adjusted to form an ink film having a desired thickness on the outer peripheral surface of the ink source roller 2. By rotating the ink source roller 2 at the speed V2, the adjusted ink film is moved to the position B (see FIG. 2) faster than in the conventional case. After the ink film reaches the position B, the speed V2 of the ink
Is reduced to the speed V1. Then, the ink source roller 2 comes into contact with the ink feeding roller 5 at the speed V1. Thereafter, the same operation is repeated. Another time chart is as shown in FIG. That is, when the ink source roller 2 is in contact with the ink feeding roller 5, the speed V is equal to that in the case of FIG.
It is rotating at 1. The ink source roller 2 does not immediately accelerate even when separated from the ink feeding roller 5,
It rotates at the same speed. Ink roller 2 after a predetermined time
Accelerates and rotates at the speed V2, and the ink feeding roller 5
Is reduced from the speed V2 to the speed V1 before coming into contact with.
Thereafter, the same operation is repeated.

As described above, the ink supply roller 2 is separated from the ink supply roller 5 while the ink supply roller 2 is separated from the ink supply roller 5.
The tip (position C) of the adjusted ink film is quickly moved to position B by increasing or decreasing the rotation speed of.
Here, the timing of rotating the ink source roller 2 at the speed V2 may be any time between (a) and (b) in FIG.
That is, at least when the ink supply roller 2 is in contact with the ink supply roller 5, the ink supply roller 2
Is controlled so that the rotation speed of the motor becomes the speed V1. Speed V2
The condition for the rotation in the condition is that the length L1 (see FIG. 2) of the ink film (section from position A to position C) of the ink source roller 2 in a state where the film thickness is adjusted (operating at the speed V1). Is longer than the maximum length L2 (see FIG. 3) of contact between the ink feeding roller 5 and the ink source roller 2. The control described above may be performed regardless of whether or not the ink key 14 is adjusted. Also, the control is performed only when the ink key 14 is adjusted, and when the ink key 14 is not adjusted, the operation is performed at the speed V1 as in the related art. You may do so. The timing for adjusting the ink key 14 may be any time, and there is no restriction on the timing. That is, the ink source roller 2 may be rotating at the speed V1 or may be rotating at the speed V2. The updated state so adjusted is quickly moved to position B.

In the present embodiment, the construction and function are as described above. When the opening of the ink key 14 is adjusted in order to change the density of the printed matter, the result is promptly converted to the ink roller group 7.
Therefore, the response delay of the density correction is shortened, the print quality can be kept high, and the waste paper due to poor quality can be greatly reduced.

Next, a second embodiment will be described.
In the present embodiment, the configuration is the same as that of the first embodiment, and the ink source roller 2 can be driven to rotate independently of the speed of the printing press main body. . Other description is omitted.

The control of the control device 3 will be described with reference to FIG. As shown in the drawing, when the ink source roller 2 is in contact with the ink feeding roller 5, the ink source roller 2 is rotated at a predetermined rotational speed (speed V1) that follows the machine speed, as in the first embodiment. Rotate. When it is separated from the ink feeding roller 5, the rotation of the ink source roller 2 is controlled as follows. The ink source roller 2 is rotated at a fixed angle at a speed V3 to form an ink film on the outer peripheral surface of the ink source roller 2. The speed V3 corresponds to the ink key 14
A sufficiently low speed at which the ink flow force at the lower end is small and the deformation of the ink key 14 and the ink source roller 2 is not more than an allowable value, and is a value appropriately determined according to printing conditions and the like. For example, the speed may be V3 'as shown in FIG. In addition, the predetermined angle is equal to or larger than the angle at which the ink feeding roller 5 comes into contact with the ink source roller 2 and rotates.
In this way, the speed of the ink source roller 2 is controlled when the ink film is formed. Then, the ink source roller 2
Is rotated at a high speed (speed V2) to a position where the ink leading end of the ink feeding roller 5 comes into contact with or separates from the ink tip.

In this embodiment, since such control is performed, regardless of the feed amount of the ink source roller 2 or a change in the machine speed,
A stable ink film can be supplied. Further, regardless of the opening degree of the ink key 14, that is, the gap S, a stable supply of the ink can be always performed. As described above, in the present embodiment, it is possible to solve a problem which has conventionally been a problem, such as an unstable ink supply state due to a change in machine speed or setting.

Next, a third embodiment will be described.
Note that, also in the present embodiment, the configuration is the same as that of the first embodiment, and a description thereof will be omitted. As shown in FIG. 5, in the present embodiment, a swing actuator 24 is provided as a swing source of a swing mechanism 23 of the ink feeding roller 5. Then, the swing actuator 24 is controlled so that the outer peripheral length of the ink source roller that contacts the ink source roller changes according to the machine speed. As the swing actuator 24, there are various methods such as a variable speed motor, a combination of a cam and a solenoid, and a combination of a cam and an air cylinder. In this manner, the adjustment of the rotation speed of the ink supply roller 2 is omitted, and the time for which the ink supply roller 5 is in contact with the ink supply roller 2 is changed according to the machine speed. I try to keep it constant. Second
As in the embodiment, the ink flow force at the lower end of the ink key 14 is constant, and the film thickness of the ink film does not fluctuate due to the machine speed, so that a stable ink film can be supplied.
Therefore, since the result of the ink adjustment appears on the paper surface, the print quality can be stabilized.

[0021]

According to the ink supply control method according to the present invention, an ink supply roller, which forms one side of an ink reservoir, is rotated by a drive system, and an ink film adjusted to a predetermined thickness by an ink key on an outer peripheral surface of the ink supply roller. In the ink supply control method for transferring and supplying the ink film to the ink feeding roller which can be brought into contact with and separated from the ink source roller, the driving system is constituted by using a driving system independent of the printing press main body. A single motor that can be arbitrarily accelerated and decelerated. The ink source roller, which is separated from the ink feed roller, rotates at high speed. When the ink key is used to adjust the ink film thickness, the result is quickly transmitted to the downstream side. However, the response delay of the density correction is shortened, the print quality can be kept high, and the waste paper due to poor quality can be greatly reduced.

Further, if the ink source roller is configured to rotate at the high speed only when the thickness of the ink film is adjusted by the ink key, it is possible to reduce the number of times the rotational speed of the ink source roller is increased or decreased. The life of the device is prolonged.

In the ink supply control method according to the present invention, an ink source roller forming one side of an ink reservoir is rotated by a drive system,
An ink supply control method comprising: forming an ink film adjusted to a predetermined thickness with an ink key on an outer peripheral surface of the ink source roller; transferring the ink film to an ink feed roller that can be separated from and contacted with the ink source roller; When the ink source roller is rotated by a motor that can be independently and arbitrarily increased / decreased using a drive system that is independent of the printing press main body, and is separated from the ink feed roller. The ink source roller is rotated at a predetermined speed at a predetermined angle to form the ink film, and the ink source roller is rotated at a high speed until the tip of the ink film reaches a position at which the ink source roller comes into contact with or separated from the ink feeding roller. When the ink feed roller is in contact with the ink source roller, it rotates at a predetermined speed that follows the machine speed of the printing press main body. When the ink film thickness is adjusted by the key, the result is quickly transmitted to the downstream side, the response delay of density correction is shortened, the print quality can be kept high, and the wasted paper due to poor quality can be greatly reduced. it can. Further, a stable ink film can be supplied irrespective of a change in the feed amount or the machine speed of the ink source roller. In addition, a stable ink film can always be supplied regardless of the opening of the ink key.

According to the ink supply control method of the present invention, an ink source roller forming one side of an ink reservoir is rotated, and an ink film adjusted to a predetermined thickness by an ink key is formed on an outer peripheral surface of the ink source roller. In the ink supply control method, in which the ink film is transferred to and supplied to an ink feeding roller that swings so as to be able to contact and separate from the ink source roller, the ink source roller rotates at a constant speed independent of the machine speed of the printing press body. Since the ink feeding roller swings so that the length of time in contact with the ink source roller is proportional to the machine speed, the ink flow force is constant, and the film thickness of the ink film does not fluctuate due to the machine speed. A stable ink film can be supplied.

[Brief description of the drawings]

FIG. 1 is an overall schematic configuration diagram of an ink supply device according to a first embodiment to which an ink supply control method of the present invention is applied.

FIG. 2 is a configuration diagram illustrating an enlarged portion of a vicinity of a lower end of an ink key in FIG. 1;

FIG. 3 is a time chart in the ink supply control method according to the first embodiment.

FIG. 4 is a time chart in an ink supply control method according to a second embodiment, and FIG.
(B) shows another example.

FIG. 5 is a configuration diagram in which the vicinity of a lower end of an ink key is partially enlarged in an ink supply control method according to a third embodiment.

FIG. 6 is an overall schematic configuration diagram of an ink supply device to which a conventional ink supply control method is applied.

FIG. 7 is a configuration diagram illustrating a part near the lower end of the ink key in FIG. 6 in an enlarged manner.

8A and 8B are configuration diagrams in which the vicinity of the lower end of the ink key in FIG. 6 is partially enlarged and shown, where FIG.
(B) shows the state immediately after the gap change, and (c) shows the state after a certain time has passed from (b).

FIG. 9 is a partially enlarged view showing the vicinity of the lower end of an ink key of another conventional ink supply device.

FIG. 10 is a view as viewed from an arrow X in FIG. 9;

11A and 11B are partially enlarged views of the vicinity of the lower end of the ink key in FIG. 9, wherein FIG. 11A shows a case where the rotation angle of the ink source roller is small, and FIG. Each case is shown as large.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 ink reservoir 2 ink source roller 3 control device 4 motor 5 ink feeding roller 6 transfer roller 7 ink roller group 8 ink application roller 9 plate cylinder 10 printing plate 11 ink 12 blanket cylinder 13 sheet 14 ink key 15 dampening device 16a, 16b Side wall 17 Support shaft 18 Swing drive device 23 Swing mechanism 24 Swing actuator A, B, C Position K Arrow L1, L2 Length S Gap t Time V1, V2, V3, V3 'Speed of ink source roller

Claims (4)

[Claims] An ink source roller forming one side of an ink reservoir is rotated by a drive system, and an ink film adjusted to a predetermined thickness is formed on an outer peripheral surface of the ink source roller by an ink key. In an ink supply control method for supplying and transferring to an ink feeding roller that can be separated from and contacted with a main roller, a driving system that is independent of the printing press body is used, and a motor that can independently and arbitrarily increase and decrease the speed of the driving system is used. An ink supply control method comprising: rotating the ink supply roller separated from the ink supply roller at a high speed. 2. The ink supply control method according to claim 1, wherein the ink supply roller rotates at a high speed only when the thickness of the ink film is adjusted by the ink key. 3. An ink source roller forming one side of the ink reservoir is rotated by a drive system, and an ink film adjusted to a predetermined thickness is formed on an outer peripheral surface of the ink source roller with an ink key. In an ink supply control method for supplying and transferring to an ink feeding roller that can be separated from and contacted with a main roller, a driving system that is independent of the printing press body is used, and a motor that can independently and arbitrarily increase and decrease the speed of the driving system is used. The ink source roller is rotated, and the ink source roller is rotated at a predetermined speed at a predetermined angle to form the ink film when the ink source roller is separated from the ink feeding roller. While rotating the ink supply roller at a high speed until the ink supply roller reaches the contact / separation position with the ink supply roller, while the ink supply roller is in contact with the ink supply roller, And rotating the printing press at a predetermined speed that follows the machine speed of the printing press body. 4. An ink source roller forming one side of the ink reservoir is rotated to form an ink film adjusted to a predetermined thickness with an ink key on an outer peripheral surface of the ink source roller. In the ink supply control method, wherein the ink supply roller is transferred to and supplied to the ink supply roller which swings so as to be able to come and go, the ink supply roller rotates at a constant speed irrespective of the machine speed of the printing press main body, and the ink supply roller is provided with An ink supply control method, characterized in that the ink supply roller is oscillated so that the length of time in contact with the ink source roller is proportional to the machine speed.