JPH1170637A - Method and apparatus for controlling supply of ink in printing press - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for markedly improving the transfer of ink between an ink fountain roller, an ink doctor and ink rollers arranged therebehind and avoiding the enhanced abrasion of those rollers in the ink amt. adjusting region outside a printing format and an apparatus for executing this method. SOLUTION: In a method and apparatus for controlling the supply of ink in an ink fountain type inking arrangement of a printing press, especially, a sheet-fed offset press, a film thickness of a prescribed value is regulated corresponding to the required ink amt. of a plate in each of ink amt. adjusting regions arranged side by side on an ink fountain roller 1 and no ink is supplied in the ink amt. adjusting regions outside a printing format. In order to form an ink film on the ink ductor within the range outside the printing format, ink film thickness not equal to zero is regulated at least at every predetermined time at least in one ink amt. adjusting region on the ink fountain roller 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the supply of ink in a printing press, in particular in a recall inking unit of a sheet-fed offset printing press, comprising an ink metering device which is positioned side by side on an ink delivery roller. The present invention relates to a method in which a predetermined film thickness is adjusted in the area according to the required ink amount of the plate, and no ink is supplied in the ink metering area outside the printing format. The invention also has an ink fountain roller that extends over the format width of the machine and an ink metering member that cooperates with the ink fountain roller so that these ink metering members can be external to the print format. The present invention relates to a device for controlling the ink supply in a printing press, in particular a reciprocating inking device of a sheet-fed offset printing press, which is operatively connected to an ink remote control having a format storage device for preventing the ink supply.

[0002]

2. Description of the Prior Art In sheet-fed offset printing presses, the ink is adjusted in the form of an ink film by means of an ink metering element on an ink delivery roller. The ink is transported from the ink fountain roller to the plate via the other ink rollers by means of an ink transfer roller which oscillates between the ink fountain roller and, in particular, an ink roller formed as a first ink kneading roller. On the inking roller, a plurality of, in particular remotely controllable, ink metering elements adjust at least one ink film, each corresponding to the required ink level in each ink metering zone. Thickness (thickness) of this ink film
Depends on the required ink amount of the plate in each printing area.

[0003] From EP 0 353 625, a console is known for a printing press, in particular for a rotary offset printing press, in which the individual remotely controllable ink metering elements in the inking unit can be adjusted. 1 for each ink metering area
With the aid of a pair of operating members, the ink metering member can be opened or closed in the selected inking unit and the desired ink metering zone to form the desired ink film thickness on the ink delivery roller. it can. In addition, this console
By double operation of the key pair, each ink metering area (of the corresponding ink metering element) is locked for global or percentage adjustment, or by double operation of the two key pairs different ink metering areas. In this case, it is possible to attach ink metering sections, which are respectively located between the ink metering sections, to a printing format. Outside the printing format, i.e. in the ink metering area where ink is not received by the printing form, the ink metering member is completely in contact with the ink fountain roller. That is, ink is not supplied via the ink discharging roller. Here, the ink is constantly scraped off because the ink metering member is constantly in contact with the ink discharge roller. That is,
In these ink metering zones, the ink fountain roller rotates in a stripping manner.

[0004] Two disadvantages result from the fact that the ink metering element is completely in contact with the ink fountain roller in the ink metering zone outside the print format. First, in the first stage, the ink transfer roller contacts only the ink metering area inside the format area. This contact takes place at the beginning of the contacting phase in the ink metering zone in which the ink metering element is adjusted at the greatest distance from the inking roller, based on the high required ink volume, i.e. the ink metering zone in which the maximum ink film thickness is present. Done in In addition, this step of forming a gap between the ink delivery roller and the ink transfer roller or between the ink transfer roller and the ink kneading roller, which depends on the ink film thickness, usually involves pressing between the rollers, which is performed at the center. That is, a corresponding deflection occurs in the roller pairs that contact each other at predetermined time intervals.

Second, since the ink metering member is completely in contact with the ink discharge roller outside the printing format, the ink discharge roller and the ink transfer roller, and the ink transfer roller that does not transfer ink in these areas. It is considered disadvantageous that the ink and the dough rollers interact with each other without ink. Particularly with the use of ink metering elements which allow very good scraping of the ink, this stripping rotation leads to increased wear of the corresponding rollers or their surfaces.

German Patent DE 40 38 574 discloses a method for controlling inking in the production of multicolor printed products in combination with special color control strips. In this method, a color control strip is used, which for each specific ink is provided with a measuring area only in the second ink metering zone. In particular, when the proportion of the printing surface is small, the ink metering member must be completely inked in areas where the plate does not have a proportion of the printing surface and where the color control strip for each ink also has no measuring area. It can be brought into contact with a roller. Confirmation of the ratio of the printing surface to each ink metering area is performed by plate scanning (temporary adjustment).

[0007] From DE-A-4 429 481, in printing with a printing plate having a small proportion of the printing surface, in order to improve the transient characteristics between the two fixed inking states, printing is not equal to zero. A method for supplying ink on a printing press is known in which the supply of ink does not take place in at least one ink metering area corresponding to the printing area having a surface area. If the proportion of the printing surface is small and evenly distributed over the plate, the ink metering members are respectively opened according to the required ink amounts required only in the second ink metering zone, The ink metering zones located between the zones can be made permanently closed.

With the two methods for controlling the ink supply described above, the ink metering and the ink flow caused thereby are optimally adapted to the needs of the printing form. But,
No suggestion can be read from this prior art as to how the ink metering member is adjusted outside the printing range, i.e. beyond the format boundaries.

[0009]

SUMMARY OF THE INVENTION The object of the present invention is described in the generic part of the method or device claim.
A method for controlling the ink supply on a printing press and an apparatus for implementing the method have been improved to enable a significant improvement in the ink transfer between the ink fountain roller, the ink transfer roller and the ink roller arranged behind it. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for avoiding the increased wear of these rollers in the ink metering zone outside the printing format and a device for implementing this method.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the method of the present invention comprises the steps of forming at least one ink layer on an ink transfer roller in order to form an ink film on an ink transfer roller outside a print format. In each of the ink metering zones, an ink film thickness which is not equal to zero was adjusted at least every predetermined time.

Furthermore, in order to solve the above-mentioned problem, in the configuration of the apparatus of the present invention, the ink remote control device has a format control device operatively connected to a format storage device, and the format control device uses the format control device. At least one ink metering element is operable outside of the print format to form an ink film thickness not equal to zero at least every predetermined time on the dispensing roller. Advantageous configurations of the invention are set out in the dependent claims.

In accordance with the invention, beyond the boundaries of the print format, the ink metering element of a particular ink metering zone is adjusted to an adjustment value that is not equal to zero toward the ink fountain roller. That is, at least one ink metering area beyond the format boundary,
The ink metering member on the ink delivery roller produces an ink film thickness that is not equal to zero at least every predetermined time. In this case, this ink film thickness which is not equal to zero can be made permanent, ie during the entire printing operation. Prior to the start of the printing operation, the ink metering zones located outside the print format are determined, and the ink metering element is adjusted to a predetermined value in each selected ink metering zone.

By appropriately adjusting the ink metering element and thus the ink film (film thickness) formed on the ink fountain roller in areas outside the printing format, the ink flow in these areas is controlled by the ink fountain roller. To the first ink mixing roller via the ink transfer roller.
At this time, the flow of the ink in the transverse direction (particularly, the action of the first ink mixing roller behind the ink transfer roller) causes
In the ink metering zone located between these zones (the ink metering element is completely in contact with the ink fountain roller), the ink is returned to the ink fountain roller again. In this case, in the ink metering zone outside the print format, the film thickness value produced by the ink metering member that is not completely in contact with the ink fountain roller is determined by the ink transferred from the ink fountain roller to the ink transfer roller. It is conveyed to the milling roller and is selected so that the ink metering element is fed back into the ink channel again through the ink metering zone which is completely in contact with the ink fountain roller. The adjustment value provided for this purpose depends on the geometry of the inking unit and in particular on the diameters of the inking roller, the ink transfer roller and the first inking roller.

In this case, the thickness of the ink film formed on the ink discharge roller is such that an ink film is formed on the ink transfer roller and the ink roller (ink mixing roller) disposed behind the ink transfer roller even outside the printing format. The ink supplied to the inking unit is selected in such a way that it is fed back towards the ink channel or ink fountain roller in the area where the ink metering member is closed. Therefore, there is no flow of ink that extends as a whole to the plate cylinder or to the inking roller cooperating with the plate cylinder. In this way, the rollers (ink transfer roller, first ink mixing roller) in the upper part of the inking unit rotate without ink, and the accumulation of ink in the lower part (inking roller) of the inking unit. It is avoided.

In another embodiment of the invention, a specific number of ink metering members are brought into firm contact with the ink fountain roller in the transition area between the format (ie, the printing area on the plate) and the area outside the format. Have been left. In other words, ink supply is not constantly performed in these ink metering zones. In this case, one,
Two or three ink metering zones can be provided as ink-free passages on the inking roller. In this case, for example, areas without ink may be located in the print format. By means of this ink-free path, the ink flows from the ink metering zone of the printing format in which the transverse ink flow (lateral ink milling) has a proportion of the printing surface (ink metering member is open) from the format boundary. Out of the way, thereby causing an accumulation of ink on the ink rollers, plate cylinders and / or rubber blanket cylinders.

According to an embodiment of the present invention, in the ink metering zone outside the print format, the ink metering members of each second ink metering zone are adjusted to a specific value which is not equal to zero. This adjustment of the ink metering member in the ink metering zone outside the print format is maintained during the entire printing run. In another preferred embodiment of the invention, the adjustments made in the ink metering zone outside the print format can be changed at predetermined intervals. Outside the printing format, for example, there is a periodic exchange between the non-inked ink metering area and the ink metering area to which the ink is supplied.

An ink remote control constructed in accordance with the present invention includes a format control device in addition to a format storage device. With this format controller,
The above-mentioned adjustments take place in the ink metering zone outside the printing format via the ink remote control. Temporary adjustment data can be supplied to the ink remote control, the format storage device and the format control device, in particular on the basis of a plate scan or on the basis of correspondingly processed pre-stage data. From these preliminary adjustment data, the ink metering areas or components which are located outside the printing format and are supplied by an adjustment which is not equal to zero, and corresponding adjustment values are determined. Furthermore, based on the provisional adjustment data, the number of ink metering areas in the ink-free path, i.e., several ink metering areas are adjusted to zero inking as a transition between the print format and the area outside the format. The decision is also made. Based on the size of the print format and the proportion of the print surface in the print format (ink consumption of the plate), the format control unit causes the ink metering members external to the print format to be second or third or respectively. In the fourth ink metering area,
It may be adjusted to a predetermined metering value that is not equal to zero, or such adjustments or adjustment recommendations may be derived from plate scan data or pre-stage data.

[0018]

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

FIG. 1 shows an ink fountain roller 1 and an ink metering member 2 which cooperates with the ink fountain roller 1. Each ink metering member has a remotely controllable adjusting drive 3. The ink fountain roller 1 extends over the format width of the machine. Therefore, a plurality of ink metering members 2 are attached to the ink discharging roller 1 side by side (FIG. 2). The individual adjusting drives 3 of the ink metering element 2 are operatively connected to an ink remote control 4 embodied as a programmable computer. After selecting an appropriate inking device from the ink remote control device 4, an operation key (not shown) is used to operate the ink metering member 2.
Can be moved toward the ink discharging roller 1.

The ink remote control device 4 has a format storage device 4.1. Format storage device 4.1
Has an ink remote control device 4 for each ink device.
Can input the format boundary as an ink metering zone (ink metering zone Zi1; Zi2) that matches the format boundary. By means of the format storage device 4.1, in combination with the program running in the ink remote control device 4, the metering member 2 of each inking device outside the printing format can be adjusted for overall adjustment (for example, percentage adjustment, parallel adjustment). Locked. That is, in such a command, only the metering members located in the format are correspondingly operated.

In addition to the format storage device 4.1, the ink remote control device 4 has a format control device 4.2 for reading the format boundaries of the individual inking devices. In addition to the format boundaries (format storage 4.1), the format controller 4.2 has the number of ink metering zones provided for the ink-free path F and a zero outside the print format. The number of ink metering zones having unequal ink film thicknesses can be entered. The format control 4.2 sends these values or data for adjustment via the ink remote control 4 in the manner described below. Format control device 4.2
Thus, for the ink metering member 2 outside the format boundary FG, a stored adjustment value or an adjustment value which can be determined from the image area S of the plate DF (by plate scanning) can be formed and implemented. .

FIG. 2 shows the individual zones Z1, Z2,. . . Z
1 shows an ink dispense roller 1 and an ink metering member 2 cooperating with the ink dispense roller 1 at n. The individual ink metering zones Z1, Z2,. . . Above the ink fountain roller 1 containing Zn, a maximum format MF is shown. In this example (this inking unit), printing is performed on a plate D whose width (format width) is smaller than the maximum format MF.
Performed at F. On this plate DF, an image area for receiving ink with S is shown. The plate DF has a corresponding area Zi
1 and Zi2. These zone numbers can be entered via the ink remote control 4 into the format storage 4.1.

Inside the format boundary F, that is, between the zones Zi1 and Zi2, the ink profile (film thickness) is determined by the ink metering member 2 on the ink discharging roller 1 according to the required ink amount of the image area S on the plate DF. The distributions s1 to sn) are adjusted. Outside the format boundary FG, the format control device 4.2 alternately adjusts the ink metering elements 2 in predetermined areas to predetermined values, and completely inks in areas located between these areas. Roller 1
Is in contact with In the area that coincides with the format boundary FG of the plate DF, the ink metering member 2 was completely in contact with the ink discharge roller 1. As described above, the area within the format boundary FG is freely selectable to form an ink-free path F. That is, the ink metering member 2 can be completely closed at one, two, or three ink metering areas at the format boundary FG.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus for performing a method according to the present invention.

FIG. 2 is a principle diagram of ink supply according to the present invention.

[Explanation of symbols]

1 ink delivery roller, 2 ink metering member, 3
Adjustment drive, 4-ink remote controller, 4.1 format storage device, 4.2 format controller, DF plate, S object (plate), FG, format boundary, F ink-free path, MF maximum format, Z1 to Zn ink metering zone, Zi
1; Zin ink metering area (format boundary F
G), S1-Sn film thickness (ink metering zone Z1-Z
n)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ulrich Jung, Germany Limburg Frank Fürsterstraße 65a (72) Inventor, Peter Hummel, Germany Gieet Lung am Stein 26 (72) Inventor Karl-Heinz Franz Germany Aschaffenburg Auraweg 4

Claims (10)

[Claims] 1. A method for controlling the supply of ink in a recall ink device of a printing press, comprising a film having a defined value according to the required ink amount of a printing plate in an ink metering zone arranged on an ink delivery roller. In a method in which the thickness is adjusted and there is no ink supply in the ink metering zone outside the print format, at least one of the inks is formed on the ink delivery roller to form an ink film on the ink transfer roller outside the print format. A method for controlling ink supply in a printing press, comprising adjusting an ink film thickness not equal to zero at least every predetermined time in one ink metering zone. 2. The method according to claim 1, further comprising the step of forming a non-zero ink film thickness at defined ink metering zones outside the printing format and supplying ink in at least one ink metering zone between the ink metering zones. The method of claim 1, wherein the step is not performed. 3. Completely blocking the supply of ink in a defined number of ink metering zones within the boundaries of the print format.
The method according to claim 1. 4. The method as claimed in claim 1, wherein the adjustment of the ink supply made in the ink metering zone outside the printing format is maintained unchanged during the printing operation. 5. The method according to claim 1, wherein the adjustment of the ink supply performed in the ink metering zone outside the printing format is changed at predetermined intervals during the printing operation. 6. The method as claimed in claim 1, wherein the adjustment of the ink supply performed in the ink metering zone outside the printing format is defined on the basis of the required ink amount of the printing form. 7. Apparatus for carrying out the method according to claim 1, comprising an inking roller extending over the format width of the machine and cooperating with the inking roller. Ink metering members, which are operatively associated with an ink remote control having a format storage device to prevent ink supply outside of the print format.
Apparatus for controlling ink supply in a call-to-print inking unit of a printing press, wherein an ink remote control (4) has a format control (4.2) operatively connected to a format storage (4.1). The format controller (4.2) causes the ink film thickness (s1 to s1) not to be equal to zero on the ink discharge roller (1) at least every predetermined time.
sn) to form a print format (DF; F
Device for controlling ink supply in a printing press, characterized in that at least one ink metering member (2) is operable outside G). 8. An ink film thickness (s1 to sn) not equal to zero is adjusted by a prescribed ink metering member (2) outside the print format (DF; FG) by the format control device (4.2). In each case at least one ink metering zone (Z1-Zn) between these ink metering members (2), the ink metering member (2) is completely in contact with the ink delivery roller (1). Apparatus according to claim 7, which is capable. 9. An ink metering member (2) of a number that can be defined by a format control device (4.2) within a range of a boundary (FG) of a print format (DF) is completely attached to an ink discharge roller (1). 9. The device according to claim 7, which is abuttable. 10. The format controller (4.2) can be supplied with the proportion of the print surface of the print format (DF), from which the adjustment of the ink metering member (2) outside the format boundary (FG) can be performed. Apparatus according to any one of claims 7 to 9, which is definable.