JPH03193350A - Ink lead-out method in printing press - Google Patents

Abstract

PURPOSE:To control an ink amount which is fewer than a minimum lead-out ink amount by a method wherein the number of lead-out times is set to be fewer than that when ink is led out at every lead-out timing in accordance with an ink lead-out amount per unit and an ink amount set value. CONSTITUTION:An ink amount to be led out is set in a condition setting device 38 per ink fountain roller 11. This ink amount is set to be 0.125% at a minimum and 120% at a maximum, thus being set in the range of 0.125% to 120% by 0.125% minimum set value. The minimum set value which is fewer than a minimum lead-out ink amount is also set in the setting device 38. In the setting device 38, the minimum or slightly larger lead-out ink amount is set as a minimum lead-out ink amount. A controller 36 equipped with a microcomputer 39 and the like controls a change-over device 14 for the ink fountain roller 11 on the basis of the set value for every output of a fountain signal.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION This invention relates to a method for feeding ink in a printing press.

BACKGROUND OF THE INVENTION As an ink drawing device for a printing press, a plurality of ink drawing rollers divided in the length direction are arranged between an ink source roller and an ink mixing roller of an ink fountain, and each ink drawing It has been proposed that the roller can be switched between a position where the roller contacts the ink source roller but does not contact the ink mixing roller and a position where the roller contacts the ink mixing roller but does not contact the ink source roller. In this device, the amount of ink is set for each ink-feeding roller, and the required ink-feeding roller is brought into contact with the ink source roller at a predetermined calling interval to draw ink, and the amount of ink set for each ink-feeding roller is adjusted to the amount of ink set for each ink-feeding roller. By controlling the time period during which the ink drawing roller is in contact with the ink source roller, it is possible to control the amount of ink drawn for each ink drawing roller.

However, in such conventional devices, the ink feed roller whose ink amount setting value is not 0 is called every time at each calling interval, so as explained next, minute ink amount control is not possible. There's a problem.

That is, since the surface portion of the ink feed roller is made of an elastic material such as rubber, it contacts the ink source roller with a certain width (contact width) in the circumferential direction. In addition, even if a command is issued to bring the ink feed roller into contact with the ink source roller and then immediately release it, the ink feed roller may be moved due to the response time of an actuator such as a solenoid for switching the position of the ink feed roller. It cannot be removed from the ink source roller immediately.

For this reason, when a single feeding operation is performed, more than a certain amount of ink is always drawn into the ink drawing roller.

If we call the amount of ink called out to the ink drawing roller while the ink drawing roller is in contact with the ink source roller for the minimum time the minimum amount of ink drawn, for example, for the ink amount setting f11100%, , the minimum amount of ink drawn may be about 5%.

In such a case, even if an ink amount of less than 5% is set, ink of 5% or more will always be called out, and an ink amount of less than 5% cannot be controlled.

An object of the present invention is to solve the above-mentioned problems and to control an ink amount that is less than the minimum amount of ink called to the ink feed roller while the ink feed roller is in contact with the inking source roller for a minimum period of time. The purpose is to provide a method.

Means for Solving the Problems In the method according to the present invention, a plurality of ink-feeding rollers divided in the length direction of the ink-feeding roller are disposed close to the ink-feeding roller for ink amount, and each ink-feeding roller is configured to ink. In a printing machine that can be switched between a position in contact with the ink source roller and a position away from the ink source roller, ink is drawn by bringing the required ink drawing roller into contact with the ink source roller at a predetermined calling interval. , a method of controlling the amount of ink drawn to the ink drawing roller by controlling the time period during which the ink drawing roller is in contact with the ink source roller according to the amount of ink set for each ink drawing roller, the ink drawing roller The minimum setting value is an amount of ink that is less than the minimum amount of ink called out to the ink drawing roller while the ink is in contact with the ink source roller for the minimum time, and the ink drawing roller is set to an amount of ink that is less than the minimum amount of ink called out. , the amount of ink drawn in one calling operation is set to be equal to or greater than the minimum amount of ink drawn, and the number of ink calls is reduced depending on the amount of ink drawn in one time and the ink amount setting value compared to the case where calling is performed every time at each calling interval. It is characterized by:

Function: If the ink amount is set to be less than the minimum amount of ink called to the ink feed roller while the ink feed roller is in contact with the ink source roller for the minimum time, the amount of ink drawn at one time will be greater than or equal to the minimum amount of ink called out. Therefore, it will be larger than the set value, but the number of calls will be reduced, so if you take the average of multiple call intervals, the amount of ink per time will be less than the minimum amount of ink called, and the ink amount will be equal to or close to the set value. Can be a value.

Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the part of the ink-priming device (lO) of a printing press.

In Fig. 1, an ink source roller (3) close to an ink amount adjusting plate (doctor blade) (2) constituting the bottom of the ink amount (1), and the first ink mixing roller ( 4) and the ink source roller (3).
) and the ink Q adjustment plate (2), remove the ink source roller (3).
) is provided with an ink drawing device (10) for transferring the ink appearing on the surface of the ink mixing roller (4).

The inking roller (4) rotates at a higher surface speed than the inking roller (3), and these surface speeds are varied in proportion to the printing speed.

As described later, the ink drawing device (I0) operates in the length direction of the ink source roller (3) (hereinafter referred to as the roller length direction).
A plurality of ink calling rollers (11) are provided.

The ink feed roller (11) is integrally moved back and forth in the roller length direction by a reciprocating device (12) which will be described later. In addition, each ink calling roller (11) is
It is forcibly rotated at the same surface speed as the ink mixing roller (4) by a calling roller drive device (13), which will be described later. Further, each ink feeding roller (11) is connected to an ink mixing roller (
4), and there is an operating position where the ink source roller (3) is in contact with the ink source roller (3) as shown by the chain line in Figure 1, and a non-operating position where it is away from the ink source roller (3) as shown by the solid line in the same figure. It can be switched to The reciprocating device (12), drive device (13), and switching device (14) of the ink drawing roller (11) are controlled by a control device (36) described later.

The ink in the ink amount (1) of the ink source roller (3) is
The ink passes through the gap with the ink amount adjusting plate (2) and emerges from the surface of the ink source roller (3). At this time, the ink source roller (3)
By adjusting the size of the gap between the ink amount adjusting plate (2) and the ink amount adjusting plate (2), it is possible to adjust the film thickness of the ink that appears on the surface of the ink source roller (3), that is, the amount of ink.

The ink that has appeared on the surface of the ink source roller (3) is transferred to the ink calling roller (II) while the ink calling roller (11) is switched to the operating position, and is transferred to each ink calling roller (11). The transferred ink is transferred to an ink mixing roller (4), which is in constant contact with the ink mixing roller (4), and further supplied to the printing surface via a plurality of rollers. By adjusting the time during which each ink feed roller (11) is switched to the operating position, the amount of ink supplied to the printing surface can be changed depending on its position in the width direction.

The ink feeding roller (11) is an ink kneading roller (4).
), so when it is switched to the operating position, the ink mixer roller (4) and ink source roller (3)
You will be in contact with both at the same time. Therefore, the ratio of the time during which ink can be transferred from the ink source roller (3) to the ink mixing roller (4) to the total operating time can be set to 1 at maximum.

Since the plurality of ink drawing rollers (11) are reciprocated in the length direction of the ink source roller (3), the surface of the ink mixing roller (4) that was generated due to the gaps between the ink drawing rollers (11) is removed. Vertical streaks, that is, non-uniform ink film thickness, are smoothed out and the ink film thickness becomes uniform.

In addition, the ink feeding roller (1) is driven by the drive device (13).
1) is forcibly rotated at the same surface speed as the ink mixing roller (4), so its rotation does not become unstable and the amount of ink is supplied accurately.

Arrangement of ink feed roller (11), reciprocating device (work 2), switching device (I4) and drive device! (13)
Although the configuration and the like are arbitrary, one example will be explained next with reference to FIGS. 2 to 4. Further, with reference to FIG. 5, an example of the electrical configuration of the ink drawing device (lO) including the control device 36) will also be described.

FIG. 2 shows the configuration of the reciprocating device (12).

A reciprocating rod (15) with a rectangular cross section extending in the longitudinal direction of the roller is disposed above between the ink source roller (3) and the ink mixing roller (4). Both ends of the moving rod (15) are received by U-shaped guide members (16) fixed to a frame (not shown). A guide pin (17) is fixed to each guide member (16), and a movable rod (15)
has an elongated hole (18) into which these guide pins (17) fit.
is formed.

The moving rod (15) is guided by the guide member (1B) and the guide pin (17) so that it can move only in the longitudinal direction of the roller. An electric motor (19) for reciprocating movement is installed at an appropriate location on the frame, and the rotation of this motor (19) is converted by a crank mechanism (20) into a reciprocating linear movement of the moving rod (15) in the roller length direction. It looks like this. Note that the reciprocating stroke of the moving rod (15) is larger than the gap between adjacent ink-feeding rollers (11) to ensure the uniformity of the ink film thickness described above. Further, the motor (19) is connected to the control device (36), and the motor (19) moves the rod (1).
5) That is, the reciprocating speed of the ink drawing roller (11) is also changed in proportion to the printing speed. Although the gap between the ink-feeding rollers (11) is exaggerated in FIG. 2, it is preferable that the gap be small. However, due to mechanical reasons, it is not possible to eliminate this gap.
In reality, it is, for example, about 3 to 10 ■■. Second
The figure shows three ink feed rollers (11), but
The number is arbitrary. Furthermore, the configuration of the reciprocating device (12) is not limited to that shown in FIG.

An ink feed roller (11) is attached to each of the movable rods (15) via a switching device (14), the details of which are shown in FIGS. 3 and 4.

The solenoid (21) case (
22) is attached, and an iron core (23) movably passes through the case (22) and the movable rod (15).

A bifurcated roller support member (24) is fixedly provided at the lower end of the iron core (23) protruding from the movable rod (15), and the roller support member (24) is fixed between the tips of the support member (24). An ink feed roller (11) is attached to the shaft (25). A flange (2B) is integrally formed in a portion of the iron core (23) in the case (22) so as to move slightly up and down above the solenoid (21).

An adjustment nut (27) that also serves as a spring receiver is screwed into the upper end of the iron core protruding from the case (22), and between this nut (27) and the upper surface of the case (22)
3) is attached with a compression coil spring (28) that urges it upward. The solenoid (21) is connected to a control device (36) via an electric wire (29).

By controlling the energization to the solenoid (21), the ink feeding roller (11) can be moved to the ink mixing roller (4).
is switched between an activated position and a non-activated position while being in constant contact with the While the solenoid (21) is not energized, the iron core (23) is moved to the upper end by the spring (28), thereby switching the ink feed roller (11) to the non-operating position. At this time, the flange (26) of the iron core (23) hits the top wall of the case (22), thereby regulating the position of the ink feed roller (11). When the solenoid (21) is energized, the iron core (23)
is attracted by this and moves to the lower end position, which causes
The ink ductor roller (11) is switched to the active position. At this time, the adjustment nut (27) hits the top surface of the case (22), thereby regulating the position of the ink-feeding roller (11), and by adjusting the position of this nut (27), the position of the ink-feeding roller (11) is regulated. The operating position can be adjusted. 1 and 3, the distance from the straight line (C) on which the center (B) of the ink drawing roller (11) moves to the center (D) of the ink mixing roller (4) is It is approximately equal to the sum of the radius of (11) and the radius of the ink mixing roller (4), and the line from the center (D) of the ink mixing roller (4) to the above straight line (
If the foot of the perpendicular line (E) drawn at C) is (F), then (F
) is the center of the ink feed roller (11) in the operating position (
B) and the center (B) of the ink ductor roller (11) in the inactive position. By doing so, it becomes possible to switch the ink feed roller (11) between the operating position and the non-operating position while always contacting the ink mixing roller (4).

Such switching of the ink drawing roller (11) and control of the time during which it is switched to the operating position are performed by a control device 36), as will be described later.

Figures 1 and 3 show the ink source roller (3) when the ink feed roller (II) is switched to the non-operating position.
Although the gap between the two is shown exaggerated, it is actually much smaller, for example, about 1 ml. Switching device (14
) is not limited to that shown in FIGS. 2 to 4. In this embodiment, the ink drawing roller (11) moves linearly to switch, but the ink drawing roller (11) may be attached to a swing arm or the like and move in an arc to switch. . Furthermore, an air cylinder or the like may be used as a driving means for the switching device (14).

As shown in detail in FIG.
) has a double structure consisting of an inner cylindrical part (30) made of a hard material such as metal and an outer cylindrical part (31) made of an elastic material such as rubber, and both ends of the inner cylindrical part (30) are equipped with rolling bearings. (32) and is rotatably supported by the support shaft (25). A drive device (electric motor) (13) is built in between the inner cylindrical portion (30) and the support shaft (25). This drive device (13) consists of a stator (33) attached to a support shaft (25) and a rotor (34) attached to the inside of an inner cylindrical part (30). The ink feed roller (11) is rotated by energizing the stator (33).At this time, the control device (36) controls the ink feed roller (11). Calling roller (
The drive device (3) is controlled so that the surface speed of the inking roller (11) is equal to that of the inking roller (4).

In the case of FIG. 4, the driving device (13) is built into the ink calling roller (11), but the driving device may be one that drives the ink calling roller from the outside.

As shown in FIG. 5, the control device (3B) includes a motor (19) of the above-mentioned reciprocating device (12), a switching device (1
In addition to the solenoid (21) and drive device (13) of 4), a call signal generator (37) and a condition setter (38) are connected.

The call signal generator (37) outputs a call signal at predetermined time intervals in synchronization with the rotation of the ink source roller (3).

The condition setting device (38) includes an ink calling roller (11).
The amount of ink to be recalled is set for each time.

This amount of ink is expressed as a percentage, with a time slightly shorter than the interval between ringing signals taken as 100%. For example, the minimum setting value is 0.125%, the maximum ink setting value is 120%, and 0.
．． The minimum setting value between 125% and 120% is 0, 12
It is set in 5% increments. This minimum set value is smaller than the above-mentioned minimum ink volume, and is also set in the setting device (38). Further, in the setting device (38), the above-described minimum ink amount or a value slightly larger than this is set as the minimum ink amount. For example, if the minimum call-up ink amount is 5% or slightly less,
% is set as the minimum ink volume.

The control device (3B) includes a microcomputer (39), etc., and controls the switching device (14) of the ink calling roller (11) based on the above-mentioned setting value every time a calling signal is output.

FIG. 6 shows the relationship between the set value of the ink amount and the amount of ink actually drawn into the ink drawing roller (11) at one time. Suppose that the contact width between the ink feed roller (11) and the ink source roller (3) is very small, and the minimum time that the ink feed roller (11) is in contact with the ink source roller (3) is very short. For example, as shown in FIG. 6(a), even if the set value becomes small, the amount of ink actually drawn into the ink drawing roller (II) at one time can be made equal to the set value. However, in reality, since the outer cylindrical portion (31) of the ink feed roller (11) is made of an elastic material such as rubber, the contact width with the ink source roller (3) is increased to some extent. Furthermore, due to the response time of the solenoid (21) of the switching device (14), the minimum time that the ink feed roller (11) is in contact with the ink source roller (3) becomes longer to some extent. For this reason, Figure 6 (b
), if the set value is greater than the above-mentioned minimum ink supply amount, take into account the contact width between the ink supply roller (11) and the ink source roller (3), the response time of the solenoid (21), etc. By controlling the switching device (14), the amount of ink drawn into the ink feeding roller (11) at one time can be accurately controlled according to the set value, but the set value may be smaller than the minimum amount of ink drawn. Even if 1
The amount of ink actually drawn into the ink drawing roller at a time cannot be made smaller than the minimum amount of ink drawn. That is, if the set value becomes smaller than the minimum amount of ink to be drawn, the amount of ink that is actually drawn to the ink drawing roller (11) at one time cannot be made equal to the set value.

Therefore, even if the set value of the ink amount is less than the minimum call-out ink amount, the control device (3B) performs the following procedure so that the average call-out amount while the call signal is output multiple times is equal to the set value. is in control.

That is, when the set value of the ink amount is equal to or greater than the minimum call-out ink amount, this set value is used as the one-time call-out amount, and the call-out operation is performed every time the call-out signal is output. In this case, since the set value is greater than or equal to the minimum ink amount, even if this value is used as the amount of ink for one time, the amount of ink for one time will be equal to or greater than the minimum amount of ink to be ejected. Therefore, as described above, the amount of ink drawn into the ink drawing roller (11) at one time can be accurately controlled in accordance with the set value. And since this kind of calling operation is performed every time,
The average call volume for multiple calls also exactly matches the set value.

If the ink amount setting value is less than the minimum ink amount,
The minimum callout ink amount is set as the amount of one callout, and the number of calls is made smaller than the number of times a callout signal is output. what if,
If a calling operation is performed each time with the amount of ink being drawn once being set as the minimum amount of ink being drawn, the average amount of ink being drawn out multiple times will be larger than the set value. However, by not performing the paging operation every time, the average number of paging operations can be made equal to the set value.

Next, referring to the flowcharts in FIGS. 7 and 8 and the time chart in FIG.
The operation of B) will be explained in more detail.

FIG. 7 shows a flowchart for setting conditions before printing.

When the power is turned on, first, in step 101,
Minimum amount of ink drawn from the setting device (38) (5%)
Load. Next, in step 102, the setting device (3
Read the minimum setting value from 8).

Next, in step 103, the setting value of the ink amount of each ink calling roller (11) is read from the setting device (38). Next, in step 104, the set value and the minimum amount of ink to be drawn are compared, and if the set value is less than the minimum amount of ink to be drawn, the process proceeds to step 105. In step 105, the minimum ink amount is divided by the minimum setting value, and the result is set as the number of decompositions M. If the minimum ink volume is 5% and the minimum set value is 0.125%, then M is 40. Next, in step 10B, the set value is divided by the minimum set value, and the result is set as the number of calls N. The setting value is 4.
In the case of 875%, N is 39, and if the setting value is 2.5%,
N is 20, and when the set value is 0.125%, N is 1. Next, in step 107, M and N are divided by their greatest common divisor, and the results are set as the final number of decompositions m and the number of calls n, respectively. The setting value is 4.875
%, m and n remain 40 and 39, and even when the set value is 0.125%, m and n remain 40 and 1. When the set value is 2.5%, m is 2 and n is 1. Next, in step 108, the amount of ink to be applied at one time is set to the minimum amount of ink to be applied, and the process is terminated. Step 10
In step 4, if the set value is equal to or greater than the minimum ink amount, the process proceeds to step 109.

In step 109, the number of decompositions m and the number of calls n are each set to 1. Next, in step 110,
The amount of calls per call is set to the set value, and the process ends.

FIG. 8 shows a flowchart for controlling the switching device (14) during printing.

When printing starts, first, in step 201, a decomposition number counter C1 is set to m. Next, step 20
In step 2, n is set in a call count counter Cn. Next, in step 203, it is checked whether a ringing signal has been outputted, and until this is outputted, step 203
Repeat step 03. When the calling signal is output in step 203, the process proceeds to step 204. In step 204, C
It is checked whether n has become 0 or not, and if it is not 0, the process proceeds to step 205. In step 205, a calling operation is performed. This calling operation is carried out by the ink calling roller (11).
This is done by switching the ink from the non-operating position to the operating position and then switching it back to the non-operating position, so that an amount of ink equal to the one-time dispensing amount set in the flowchart of FIG. as called,
The time period during which the ink feed roller (11) is in contact with the ink source roller (3) is controlled. Next, step 206
Then, 1 is subtracted from Cn and the process proceeds to step 207.

If Cn becomes 0 in step 204, the process directly advances to step 207.

In step 207, 1 is subtracted from CI, and in step 20
Proceed to step 8. Step 208 checks whether C- has become 0, and if it has become 0, returns to step 201 and returns 0.
Otherwise, the process returns to step 203.

When the set value of the ink amount is equal to or greater than the minimum ink amount (5%), m and n are both set to 1 in the flowchart of FIG. 7. Therefore, in the flowchart of FIG. 8, each time a calling signal is output,
The calling operation of step 205 is always executed (see FIG. 9).

When the set value of the ink amount is 4.875%, m is set to 40 and n is set to 39 in the flowchart of FIG. Therefore, in the flowchart of FIG. 8, the calling operation of step 205 is executed 39 times while the calling signal is output 40 times (see FIG. 9). and,
Since the call volume per call is 5%, the average call volume per call during 40 ring signals is 4,875% (-5X3
9/40), and the ink can be recalled according to the set value.

When the set value of the ink amount is 2.5%, m is set to 2 and n is set to 1 in the flowchart of FIG. Therefore, in the flowchart of FIG. 8, the calling operation in step 205 is executed once while the calling signal is output twice (see FIG. 9). That is, a calling operation is performed every other time of the calling signal. Since the amount of ink called at one time is 5%, the average amount of ink called out per time between the two call signals is 2.5% (-5X1/2), and the ink can be called up as per the set value. .

When the set value of the ink amount is 0.125%, m is set to 40 and n is set to 1 in the flow chart of FIG. Therefore, in the flowchart of FIG. 8, the calling operation in step 205 is executed once while the calling signal is output 40 times (see FIG. 9). Since the amount of calls per time is 5%, the average amount of calls per inlet during 40 ring signals is 0.125% (-5X1/4
0), and the ink can be recalled according to the set value.

In the above embodiment, when the set value of the ink amount is less than the minimum ink amount, the amount of one ink to be called out is made equal to the minimum amount of ink to be called out, but it may be set to be slightly larger than the minimum amount of ink to be called out. For example, if the minimum ink volume is 5% and the set value is 3%, the amount of ink to be recalled at one time is set to 6%,
If the ringing operation is performed once every two ringing signals, the average number of calls per signal will be as per the set value (6X1/
2-3).

Further, the present invention provides a conventional ink feeding device in which a plurality of ink feeding rollers are switched between a position in which the plurality of ink feeding rollers contact an ink source roller and do not contact an ink mixing roller, and a position in which a plurality of ink feeding rollers contact an ink mixing roller and do not contact an ink source roller. It can also be applied to

Effects of the Invention According to the method of the present invention, as described above, it is possible to control the amount of ink that is less than the minimum amount of ink drawn to the ink drawing roller while the ink drawing roller is in contact with the ink source roller for the minimum time. It becomes possible.

[Brief explanation of drawings]

Fig. 1 is a schematic side view of an ink drawing device showing an embodiment of the present invention, Fig. 2 is a perspective view showing an ink drawing roller and its reciprocating device, and Fig. 3 is a cutaway of the switching device of the ink drawing roller. 4 is a cross-sectional view taken along line IV-IV in FIG. 3, FIG. 5 is a block diagram showing the electrical configuration of the ink drawing device, and FIG. 6 is a diagram showing the amount of ink. Graph showing the relationship between the setting value and the amount of ink actually drawn into the ink drawing roller at one time, Fig. 7 is a flowchart showing one example of the processing of the control device, and Fig. 8 shows other processing of the control device. FIG. 9 is a time chart showing an example of the ink drawing operation of the ink drawing device. (1)...Ink amount, (3)...Ink source roller,
(10)...Ink calling device, (11)...Ink calling roller, (14)...Switching device, (3B)
···Control device. Above Figure 4

Claims (1)

[Claims] A plurality of ink feeding rollers divided in the length direction of the inking source roller are disposed close to the ink source roller of the ink fountain, and each ink feeding roller is arranged at a position where it contacts the ink source roller. In a printing machine that can be switched to a position away from the ink source roller, the required ink feed roller is brought into contact with the ink source roller at a predetermined calling interval to draw ink, and the settings are set for each ink feed roller. A method of controlling the amount of ink drawn to the ink drawing roller by controlling the amount of time that the ink drawing roller is in contact with the ink source roller according to the amount of ink drawn, The minimum setting value is the amount of ink that is less than the minimum amount of ink called out to the ink drawing roller while in contact, and the ink amount of one calling operation is Printing characterized by setting the amount of ink to be called out to be equal to or more than the minimum amount of ink to be called, and reducing the number of times of calling according to this one time ink calling amount and the ink amount setting value compared to the case where calling is performed every time at each calling interval. How to call ink in the machine.