FIELD OF THE INVENTION
The present invention is directed to an ink metering device of a printing couple and to a method of controlling the ink metering device. The ink metering device has a number of physical zones that are arranged side by side in the longitudinal direction of the printing couple cylinders. These zones can be adjusted separately using metering elements for each zones.
BACKGROUND OF THE INVENTION
A control device for controlling the printing of webs of material is known from DE 198 56 675 A1. An analysis table, with a group of keys for individually controlling the opening and closing of ink duct screws, is provided. The spacing of the keys from one another corresponds to the physical spacing of the respective ink duct screws.
A control element, which is situated beneath a sheet of paper that has been inspected by the press operator, and which is brought into a position that corresponds to a strip of the printed image that is to be corrected is disclosed in DE 42 16 440 B4. An automatic recognition system adjusts the relevant ink key for this zone and also for adjacent zones.
DE 10 2004 018 743 A1 discloses a device for visualizing ink metering element settings using a number of display devices. The number of display devices corresponds to the number of ink metering elements.
An ink metering device is known from DE 10 2004 022 700 B3. A panoramic ink zone, which is located between two single pages, is assigned on a display screen to both a display bar for one printed page and to a display bar for the other printed page. To prevent a contradictory adjustment via one and the same control element, a mean value for the two values that are desired by the press operator is determined. The mean value is taken into account by the shared control element.
DE 10 2004 054 599 A1 discloses a forme cylinder of a printing press. The forme cylinder supports a plurality of printing formes side by side in the axial direction.
SUMMARY OF THE INVENTION
The object of the present invention is to provide an ink metering device of a printing couple and a method of controlling such an ink metering device so as to allow standardization for different machine widths.
The object is attained in accordance with the present invention by the provision of an ink metering device of a printing couple including a forme cylinder and an inking unit. The ink metering device has a number of physical zones which are arranged longitudinally side by side in the direction of the forme cylinder. Each of these physical zones can be adjusted individually using metering elements. These metering elements control the quantity of ink to be applied in each physical zone. A control station is provided with a number of operator elements which are assigned to virtual zones of a printed page and which are usable for controlling the metering elements.
The benefits to be achieved in accordance with the present invention consist particularly in that a cost-effective and standardizable solution for inking units in newspaper printing presses is devised. The previous high cost of the customary small series production of each ink fountain and the corresponding metering elements specific to the widest variety of press and/or product formats can be decreased substantially, at least over broad areas or for series of related printing formats.
By adjusting the offsets, which arise as a result of the standardized metering elements, to the technical operating conditions using algorithmic calculations, and particularly by using a computer-supported software solution, operation can be carried out in the customary manner without significant cost to the printer.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention are represented in the set of drawings and will be specified in greater detail in what follows.
The drawings show in
FIG. 1 a schematic representation of a printing couple and a control station for a first machine width; in
FIG. 2 a schematic representation of a printing couple for a second machine width, with an inking unit having a lower zonal segmentation in relation to the control station; and in
FIG. 3 a schematic representation of a printing couple with an inking unit having a higher zonal segmentation in relation to the control station.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A printing couple 01 of a printing press is indicated only schematically in FIG. 1. This printing couple 01 may preferably be a newspaper printing couple 01 of a newspaper printing press. Printing couple 01 has at least one printing couple cylinder 02, such as for example, a forme cylinder 02, and also has an inking unit for use in inking the forme cylinder 02. The inking unit has at least one ink roller 03 and an ink metering device 04, which ink metering device 04 works in cooperation with the ink roller 03 to achieve inking of the forme cylinder 02. A print substrate 06, especially a paper web 06, can be printed by the printing couple 01. The printing couple 01 is preferably embodied as an offset printing couple for newspaper printing, and has a transfer cylinder, which is not specifically shown, and which is situated between the forme cylinder 02 and the paper web 06. In newspaper printing, as opposed to in high-quality commercial or sheet offset printing, uncoated or only lightly coated paper, such as, for example, with a coating weight of up to 20 g/m2, and especially with a coating weight of up to a maximum of 10 g/m2, is printed as the print substrate. Depending upon the type of inking unit, which is being used one or more additional rollers can be arranged between ink roller 03 and forme cylinder 02. The inking roller 03 can be provided as an ink fountain roller of a film inking unit, as an ink fountain roller of an ink pumping system or as an anilox roller of an anilox or short inking system. The forme cylinder 02 has a plurality of removable printing formes, which are not specifically shown, such as, for example two, four or six, printing formes depending upon the web width, arranged on its outer periphery. These printing formes can be arranged for example, side by side in the axial or longitudinal direction of the forme cylinder 02.
A machine width M1, and specifically an effective width of the printing couple cylinder 02, is usually adjusted to the maximum width of the print substrate or of the web of material to be printed. In newspaper printing, this machine width corresponds, for example, substantially to somewhat more than a whole number multiple of the width of one newspaper page of the desired maximum product format, or to the width of all of the printing formes that can be arranged side by side on the forme cylinder 02. Press manufacturers therefore design and supply newspaper printing presses of different machine widths for use by different publishing houses or for use by the print shops that serve them.
The print images to be applied to the print substrate 06 ordinarily require an amount of ink that varies across the width of the print image. This ink amount varies, based upon the print image, in order to achieve the desired ink density and thereby the desired inking across the width of the print image.
To ensure proper individual ink zone inking, over the entire printing width, the ink metering device 04 has a plurality of individually adjustable metering elements Di (i=1 . . . m; with mε![]()
), side by side in an axial direction, with which plurality of individual adjustable metering elements Di the supply of ink can be controlled in each corresponding zone ZP,i (i=1 . . . m; with mε![]()
); index wherein P is used for identification of “physical” zones. The ink metering device 04, having a plurality of adjustable zones ZP,i can be configured in a variety of ways. In the several drawing figures, the ink metering device 04 is embodied with a plurality of metering elements Di which are configured as so-called ink blades Di, or scraping elements, which ink blades D can be adjusted individually, in terms of their distance from the circumferential surface of the roller 03, via drives, which are not shown here. Based upon the gap width of this distance, the scraping by the ink blades Di leaves a thicker or a thinner film of ink on the circumferential surface of the inking roller 03, which has been placed in contact beforehand with an ink reservoir. In order to successfully ensure individual inking over the printing width or over the width of the ink fountain 04, the gap between inking roller 03 and metering element Di is adjusted by zone ZP,i, for example, by using the drives, which are not shown here, for the individual metering elements Di.
In an embodiment of the present invention, which is not specifically illustrated here, a plurality of pumps Di or a plurality of outlet openings Di, each of which is provided with valves that are controllable with respect to flow and which are arranged in the flow path, can also be provided for use as the metering elements Di. The ink metering device 04 and the method for controlling the ink metering device 04 will be described, by way of example, within the context of a so-called ink fountain 04 having an ink reservoir, such as an ink trough, and including the plurality of ink blades Di. The principle which will be described in relation to the ink blades Di can also be applied to every other embodiment of metering elements Di that form physical zones ZP,i.
In newspaper printing such as, for example, in inking units of newspaper printing presses, different machine widths M1; M2 are offered for different maximum product formats. Ordinarily, however, inking units, that are adapted specifically to these respective machine widths M1; M2, are used for these different machine widths M1; M2. The segmentation of the physical zones ZP,i, which is based upon a width bs or a page width bs of one printed page S, is always chosen as a whole number wherein, for example, the number for Zp may equal 8. Thus, for example, for a newspaper printing press having a wider product format, an inking unit having a specific number of wider metering elements Di or zones ZP,i such as, for example, having eight such zones, has heretofore been used. For a newspaper printing press having a narrower product format, an inking unit having the same number, such as, for example, eight zones or having a different whole number of metering elements Di or zones ZP,i, each having a smaller physical zone width bp, has been used. Overall, an even number of zones ZP,m corresponds to the width of the printed page. The number of adjustable physical zones ZP,i is ordinarily reflected in the number of operator elements Bj (j=1 . . . n, with nε![]()
) with the corresponding virtual zones ZV,j (j=1 . . . n, with nε![]()
) on a control station 07. In FIG. 1, for each printed page S to be placed on the control station 07, a number, such as, for example, a virtual zone number Zv equal to 8, of operator elements Bj, or of pairs of operator elements, each characterized by + and −, and being embodied as push buttons, for example, are provided. With the use of these operator elements B, the press operator can control the metering elements Di and thereby can control the gaps to the physical zones ZP,i. By pressing “+”, for example, the flow of ink is increased, through an enlargement of gap width or through an increase in pump power, and by pressing “−”, for example, the flow of ink is decreased, through a reduction of gap width or through a decrease in pump power. In this connection, as depicted in FIG. 1, the numerical and the spatial segmentation of the virtual zones ZV,j on the control station 07, as also depicted in FIG. 1, corresponds to the numerical and to the spatial segmentation of the physical zones ZP,i on the inking unit. If a presetting system 08 is provided, the required area coverages or ink densities can also be converted to the positioning of this whole number of metering elements Di or zones ZP,i from product definition in the production stage, through the pre-printing stage, up to the presetting system 08. In FIG. 1, a double-sided newspaper page, with each page having a page width bS and the allocated operator elements Bj and/or virtual zones ZV,j, with the virtual zone widths bV, is represented schematically in the lower portion of the diagram. In this case, the virtual zone widths bV that apply to the pages placed on the platform correspond to the physical zone widths bP on the inking unit. The number of virtual zones ZV,j per printed page S corresponds to the number of active physical zones ZP,i. An active, effective width be of the ink metering device 04, such as, for example, the area with metering elements Di, which is required for the present machine width M1; M2, corresponds substantially to the machine width M1; M2 or to the maximum web width.
In the typical configuration of the ink metering device 04 as being specific to a particular machine width, it is a disadvantage that especially the metering elements Di, have a high structural design costs. The usual disadvantages, that are known for very small series production, apply.
The method and apparatus of the ink metering device, as will be described in what follows, is based upon the concept of eliminating the requirement of specifically configured ink metering devices 04, and especially on the elimination of the metering elements Di, for each specific machine width M1; M2 of a printing press 01 used in newspaper printing. Instead, in accordance with the present invention, the method and apparatus is directed to using at least the same metering elements Di, and advantageously even the same ink metering devices 04, at least within certain limits, for various different machine widths M1; M2.
In FIG. 2, there is depicted a printing couple 01 and a control station 07, which are illustrated schematically, and which are provided having a smaller product format and a narrower machine width M2 than the press which was depicted in FIG. 1. In this printing couple, a plurality of printing formes, which are narrower than those associated with the press of FIG. 1, are arranged side by side on the forme cylinder 02, for example. The support surface on the control station 07 and the width of the group of operator elements Bj or the totality of the virtual zones ZV,j is also smaller or narrower in configuration, corresponding to the product to be printed. In FIG. 2, an ink fountain 04, which was structured, for example, for use with a machine width M1 from FIG. 1, is shown. The number of virtual zones ZV,j on the control station 07 that are relevant to the printed pages S is the same, for example, as was the number of such virtual zones Zvj for the press from FIG. 1, but each of the virtual zones ZV,j have a narrower zone width bV in FIG. 2. However, the ink fountain 04 has metering elements Di or has physical zones ZP,i. The zone width bP of the physical zones ZP,i or of the metering elements Di is now different from the zone width bV of the virtual zones ZV,j of FIG. 2. In this case, it is larger. The virtual segmentation of the zones ZV,j, on the control station 07 or at the pre-print stage, which is based upon the printed page width, or the machine width M1; M2, is different from the physical segmentation of the zones ZP,i on the ink metering device 04, which is based upon the printed page width, or on the machine width M1; M2. Whereas the virtual segmentation is always a whole number, a virtual segmentation that is based upon the printed page width or effective width be can also deviate from a whole number. For example, in FIG. 2 this virtual segmentation can be approximately 6.3 per printed page S. In this case, segmentation is understood as the quotient of the number of side by side printed pages S taken into consideration and the number of allocated zones ZV,j, ZP,i projected across this width bS. For example, in FIG. 2: virtual segmentation 8/1 or 16/2, etc., and physical segmentation 6.3/1 or 12.6/2, etc. The segmentations of the physical and virtual zones ZP,i, ZV,j can also differ in terms of spatial positioning, based upon the printed page S. In the present case, the differences consist in segmentation with respect to the number and the positioning of the zones ZP,i, ZV,j.
If the press operator were to perform an adjustment, using the operator element B3 for its virtual zone ZV,3, for example, and thereby actuating the drive of the metering element D3, as is customary in newspaper printing, and without taking into account the different zone widths bp; bV and/or the different zone positions, this would be incorrect, as may be seen in FIG. 2. To allow inking units having the same physical zone width bp to be used for different machine widths M1; M2, an algorithmic calculation A, which will be referred to here as an algorithm, is provided, which algorithm takes into account the differences between the virtual and physical zones ZV,j, ZP,i in terms of number and/or position and/or width, and converts these appropriately.
As is shown in FIG. 2, the inking unit or the metering device 04 can have more than the number of metering elements Di that are absolutely necessary, or can have only as many metering elements Dm as are required to fully cover the effective width be, such as, for example, the present machine width M2. In the configuration of FIG. 2, seven metering elements Di are required per margin side, because six are insufficient. In the first case, the same metering device 04 can be used for different machine widths M1; M2, and in the second case at least the same metering elements Di can be used for different widths of the metering device 04.
If, in the example depicted in FIG. 2, the print operator uses the operator element B3 to adjust the virtual zone ZV,3 assigned to a printed page strip, for example, the algorithm A is then used to perform a conversion, so that the drive of the metering element D4 is actuated. Advantageously, the magnitude of the coverage or of the overlap between the position and the width of the virtual and physical zones ZV,3 and ZP,4 is taken into account with respect to the magnitude of the actuation signal. Because, in this case, the physical zone ZP,4 is wider than the allocated virtual zone ZV,3, the required actual change in the gap width is smaller than the virtually required change. If, as shown in FIG. 2, the virtual zone ZV,2 affects a plurality of the physical zones ZP,i, in this case affecting ZP,4 and ZP,3, a suitable conversion is performed such that a plurality of metering elements Di, in this case D4 and D3, are correspondingly positioned, or their drives are correspondingly actuated, advantageously taking their coverage into account. The same conversion principle provides the basis for the, or for an algorithm for a presetting system 08, or for the prepress stage, if the preset values for the physical zones ZP,i are to be determined from the otherwise customary standardized, whole number coordinated zones. It is advantageous, however, if, in the presetting system 08 or in the prepress stage, the actually implemented physical zones ZP,i are already accounted for in the calculation of the preset values from the required area coverages or ink densities, and are stored there in the corresponding programs.
In another preferred embodiment of the principle of the present invention, as described in connection with FIG. 1 and FIG. 2, in FIG. 3 another embodiment of a metering device 04 is shown. In this embodiment, the width bp of each of the physical zones ZP,i is narrower than is the width bV of the corresponding virtual zones ZV,j on the control station 07 or in the standard settings of the presetting system. What has been described above, in reference to FIGS. 1 and 2, is similarly applicable in the embodiment of FIG. 3. The virtual and the physical or the effective segmentation of the zones ZV,j, ZP,i are again different from one another. The algorithm A again ensures that when a specific virtual zone ZV,j is selected, a corresponding transfer to the relevant metering element Di or to the corresponding metering elements Di, or to their drive or drives occurs. Here, the physical segmentation is in whole numbers, in this case nine, by way of example. However it could also differ from a whole number, based upon the printed page width or on the effective width be of the ink metering device 04. The virtual segmentation, or the number of zones ZV,j or operator elements Bj per printed page S, is a whole number and, in this case, is eight.
In the embodiment which is depicted in FIG. 3, if the press operator wishes to use the operator element B12 to modify the virtual zone Zv,12 which is allocated to a printed page strip, for example, the algorithm A will perform a conversion such that the drives for the metering element D14 and for the metering element D15 are both actuated. The magnitude of the respectively necessary changes to the gap can then again take into account the degree of coverage or overlap between the relative position and width bV; bp of the relevant virtual and physical zones ZV,j, ZP,i.
In general, the ink metering device 04 has a number “m” of metering elements Di such that the total of the widths bp of the zones of the number “m” of metering elements Di is greater than, or is equal to the machine width M1; M2 or the maximum web width. The width of the ink metering device 04 is thus configured accordingly. If, as in the case of the examples or the embodiments of FIG. 2 and FIG. 3, metering elements Di are provided in margin areas of the ink metering device 04 which are outside of the effective width be, then in the algorithm A, or in the press control or presetting, it can be provided that these margin area metering elements Di are generally adjusted to a closed gap. In an advantageous variation of the present invention in relation to FIG. 2 and to FIG. 3, it is provided that a varying total width of the ink metering device 04 is permitted, but only in stages of the same metering elements Di that are used for different machine widths M1; M2. In other words, the number “m” of metering elements Di in the ink metering device 04 is such that the total of the widths bp of the zones ZP,i is greater than, or is equal to the machine width M1; M2. However, an (m+1)th metering element Dm+1 would lie completely outside of the effective width be or would lie outside of the projection of the machine width M1; M2.
The control station 07 therefore continues to be embodied, as is customary, with a whole number, and advantageously with an even whole number, “n”, of virtual zones ZV,j and/or with the corresponding number “m” of operator elements Bj, such as, for example, “n” pairs of push buttons Bj. The ink metering device 04 is configured with a different segmentation of zones ZP,i of a standardized width bP and optionally with a different number “m”. The offsets between virtual and physical zones ZV,j, ZP,l, which are dependent upon format and/or number of zones and/or zone width, are converted and are taken into account using the algorithm A, especially with computer support. Corresponding computing assemblies, containing the algorithm, are provided for this purpose. The algorithm A can be a function, among other things, of the machine width M1; M2 defined by the maximum web width and/or of the number “m” of physical zones ZP,i or of metering elements Dm and/or of the number “n” of virtual zones ZV,j or of operator elements Bj and/or of a width bP of the physical zones ZP,i. The algorithm A contains fixed rules for the conversion or for the consideration of the offsets or of the difference in the number and/or the position of the zones ZV,j; ZP,i. These fixed rules and/or the aforementioned input parameters, such as machine width, “m”, “n”, and the like can be defined, but stored in the computing assembly so as to be modifiable by press operators.
In the presetting process, the preset values for the metering elements Di or for the area coverages can advantageously be based directly on the physical zone number “m” and on the physical zone width bP. It is also possible, however, for the preset values or for the area coverage values to be based on the zone number “n” on the control station 07, converted there using the algorithm A to accommodate the physical conditions in the manner described above, and acted upon by those of the metering elements Di or their drives.
For all the examples or embodiments depicted in FIG. 2 and in FIG. 3, or the operating types, in which the segmentation of physical and virtual zones ZP,i, ZV,j, based upon the printed page width, differs, a plurality of metering elements Di, such as, for example, at least two metering elements, are assigned to at least one of the operator elements Bj via the computing assembly or the algorithm which is implemented therein, or are relevant with respect to control. In turn, a plurality of operator elements Bj, and especially two such operator elements Bj, can be assigned to one of the plurality of metering elements Di, based upon overlap. The plurality of metering elements Di that are relevant to an operator element Bj are preferably positioned taking into account the degree of their coverage in relation to the operator element Bj.
For the aforementioned preferred embodiments of the present invention, which are illustrated in FIG. 2 and in FIG. 3, it is also characteristic not only for a metering element Di, which is situated between two printed pages S, to be assigned two operator elements Bj of two adjacent printed pages S, but also for an adjustment to the overlap to be made for a plurality of operator elements Bj and metering elements Di which are assigned to a printed page S, using the algorithm A. Therefore, based upon the printed page S, a plurality of zones are offset with respect to their position, or are different in terms of their number.
While preferred embodiments of an ink metering device of a printing couple and a method of controlling the ink metering device, in accordance with the present invention, have been set forth fully and completely hereinabove, it will be apparent to one of skill in the art that various changes in, for example, the drives for the cylinders, the specific ink being metered and the like could be made without departing from the true spirit and scope of the present invention which is accordingly to be limited only by the appended claims.
Patent Application
20090320702
