JP2998893B2 - Printer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the switching of a number of printing mechanisms and at least one, each between two printing mechanisms, from one-sided printing to one-sided and back-side printing. And a multicolor sheet printing machine for one-side and back-side printing, comprising a switchable sheet-direction changing device. BACKGROUND OF THE INVENTION In the recent development of multicolor printing, densitometers or other color testers have been provided for different width areas of a printing sheet. Is used to continuously monitor the consistency of the color densities of the various colors in the individual width regions between the predetermined standard values of the actual printed matter. If a pre-given color tolerance for the desired standard value is exceeded, an alarm indication is generated, which indicates to the operator that adjustment of the inking device is necessary in one or many width areas, or Immediately re-adjust the ink supply to the corresponding width region in a closed loop. Only the densitometer will be described below for simplification. However, all other types of color testers can be used instead. In printing presses, in particular in offset-sheet printing presses with a large number of printing units, each including an inking device and a large number of cylinders, and in multicolor printing presses up to now the printing of the printed matter Color density (Farbdensi
For the control of (taet), take out the printed sheet from the sheet storage (Bogenablage), measure the color density at many positions of the printed color density-measurement stripe (meβstreiben) together with the density, When deviations from the pre-determined color densities occur, it is necessary to adjust the individual inking devices by means of adjusting devices acting on the ink blades, both in the transverse direction of the printed sheet and for the individual colors. There was. Such a method of operation requires constant monitoring of the printed matter. This method of operation is time consuming, hinders the continuous printing process and does not prevent the production of large amounts of debris. [0004] Known attempts to eliminate this problem include:
Disposing, in at least one cylinder facing the outwardly directed, at least partially printed surface, a density measuring device for measuring the color density of a color test area of the printed matter, in which case Standard value presetting (Soll-Vorgabe)
And an inking device or a plurality of inking devices is provided with a control element (Stellglied), which is activated by the control output of the adjusting device. In this known solution, a density measuring device is arranged in a measuring cylinder (meβzylinder), which is the transfer cylinder and sheet feeder of the last printing unit.
(Bogeuasleger). This proposal,
Each printing unit is provided with a density measuring device, which is arranged on an intermediate cylinder which is directly connected to the printing unit. However, in practice this known solution requires two additional cylinders each to reach the cylinder, where the printed side is outward and to which a densitometer can be attached. . In this form, in a multicolor sheet printing machine, which can be switched from one-sided printing to one-sided and backside printing, and vice versa, when adjusting one-sided and backside printing,
The control of the various color densities on both sides of the sheet cannot be performed at all or without any other measures. [0005] The object of the present invention is therefore based on the printing of a multicolor printing press, which is switchable from single-sided printing to single-sided and back-side printing, in which the user has to press the machine at the time. Regardless of how it is adjusted,
The color density can be continuously inspected when printing on one side and the back side, and the cost of the density measuring device is as small as possible (number)
Can be inspected. In this case, it must be taken into account that such a density test on both sides of the sheet can be performed at any possible adjustment of the machine. For example, in a multi-color sheet printing machine where many sheet transport devices are between individual printing mechanisms or printing areas, for example, if the operator of the printing press (Betreiber) is a machine having a total of five printing mechanisms, one color is used. To one-sided printing, and four colors to backside printing,
Or two colors for one-sided printing and three colors for back-side printing, three colors for one-sided printing and two colors for back-side printing, or four colors for one-sided printing and one color for back-side printing, in some cases. However, depending on whether one wants to print five colors in one-sided printing, it is conceivable that sometimes one sheet transport device and sometimes another sheet transport device can be used as a sheet redirection device. SUMMARY OF THE INVENTION In accordance with the invention, it is an object of the present invention to provide a densitometer or other color tester for control of one-sided printing, each in the sheet running direction of the last one-sided printing. Place the entire machine cylinder (where the one-sided side of each sheet is on the outside) after the area, and install a densitometer or other color tester for control of backside printing at the end of the machine. This is solved by placing the back side printing after one printing area. [0007] In such an arrangement, each sheet can be inspected for density on both the double-sided or single-sided and the reverse-side printed side with as little cost as possible, and continuously and with one-sided and reverse-sided printing. Can also be checked during each optional adjustment. [0008] The present invention can be realized by various means. For example, it is also possible to mount a density measuring device for one-sided printing on the last printing cylinder, respectively, after the last one-sided printing area and before the next sheet one-way turning device. However, it is also possible to arrange this density measuring device for one-sided printing on the cylinder of the sheet-reversing device after the last one-sided one-printing area (here the one-sided printing side of the sheet is on the outside). In addition, the density measuring device for one-sided printing may be placed on the cylinder of the sheet transfer device between the one-sided printing area or the cylinder after the last one-sided printing area (here, the one-sided printing side of each sheet). (Located outside) is also possible. In a further embodiment of the invention, it is reasonable for the individual densitometers of the concentration measuring device to be mounted on a common Bruecke, which are removable.
It is exchangeably fixed in the printing press. That is, in a printing press provided with a number of direction change devices (in this case, of course, only one sheet direction change device always works).
Only one density measuring device is required, which can be fixed at various places in the printing press, i.e. each can be fixed before an effective sheet diverter. In this way, the cost of the densitometer or color tester is particularly reduced. When the width area of the sheet to be inspected for color density is very narrow for reasons of high accuracy, it may be necessary to use a densitometer or other color tester, even a densitometer for one-sided printing, on the back side. Even with densitometers for printing, it may happen that they cannot be mounted side by side on a common bridge. It is therefore proposed according to the invention for this case to be mounted on one or many cylinders of the entire printing press, wherein the one-sided or back-sided side of the sheet to be inspected respectively lies outward. ing.
In this case, for example, if two bridges are provided for their mounting, the densitometer can be divided into two bridges by different colors to which the individual densitometers respond, or one bridge Are the first, third and fifth sheets
It is also possible to maintain densitometers for the same width region, while other bridges hold densitometers for the second, fourth, sixth, etc. width regions of the sheet. BRIEF DESCRIPTION OF THE DRAWINGS The invention is explained in more detail below by means of an embodiment schematically illustrated in the drawings. DESCRIPTION OF THE PREFERRED EMBODIMENTS The printing mechanism is shown consecutively from 1 to 6 in FIGS. It is represented by an offset printing mechanism as a pure example. However, the application of the invention can be used for any other kind of printing mechanism. The printing press according to FIG. 1 has six printing mechanisms 1 to 6 and relates to a six-color printing press. The sheet feeder is indicated by 7 and the sheet feeder is indicated by 8. Each printing mechanism has a printing plate cylinder 9, a rubber cylinder 10 and a pressure cylinder 11, these cylinders being provided with reference characters only in the case of the printing mechanism 1. A small cylinder 12 between the two printing mechanisms 1 and 2
And a sheet transfer (Ubergabe) device comprising a double cylinder 13 and a second small cylinder 14. Reference numeral 15 denotes a delivery cylinder of the sheet feeding device 8. A standard small cylinder 12 of the sheet transfer device is provided between the printing mechanisms 2 and 3, but a sheet redirection device (Wendeeinrichtung) in the form of a larger cylinder 17 and a smaller cylinder 18 is provided. . Both cylinders 17 and 18 are painted black to distinguish them from the cylinders of a pure sheet transfer device. Sheet direction changing device 17,
If 18 is intended for pure sheet transport, the entire machine operates with six colors-one-sided printing, so that only one density measuring device 16 is required after the last printing machine 6 because the sheet surface This is because only six colors are printed. On the other hand, when the sheet direction changing devices 17 and 18 are switched to one-side printing and back-side printing, another density measuring device 19 is required.
It is between 7, 18 and the last single-sided printing area, i.e. in the printing area of the printing mechanism 2. Here, the sheet is printed on one side in two colors-one-sided printing by the printing mechanisms 1 and 2 and in the printing mechanisms 3 to 6 in four-color backing, where the first two-color printing is carried out by the density measuring device 19. , And the four color prints on the side of the other sheet are controlled by a density measuring device 16. FIG. 2 shows a six-color printing press, also provided with six printing mechanisms 1-6. The machine has two sheet-reversing devices 17, 18, one between the printing mechanisms 1 and 2, and the other between the printing mechanisms 2 and 3. Both sheet direction change devices 17, 18
Is excluded, the machine operates with six colors-one-sided printing. Sheet direction changing device 1 between printing mechanisms 1 and 2
When only 7, 18 have been inserted (einschalten), the sheet-reversing device between the printing mechanisms 2 and 3 has been removed (ansschalten), on the other hand, and the machine has a single-color one-sided printing and a five-sided printing.
Works with color-back printing. On the other hand, the printing mechanism is 2
When only the left side of the sheet reversing device 17, 18 located between the first and second printing units 1 and 2 enters, and the preceding direction reversing device between the printing mechanisms 1 and 2 is excluded, the two-color one-sided printing and 4.
It works with color reverse printing. In this machine, the last printing mechanism 6
The sheet direction changing device 1 arriving first in one direction in the sheet traveling direction, in addition to the density measuring device 16 located after
Other density measuring devices 19 are provided between the printing mechanisms 2 and 7 and 18 and between the second sheet direction changing devices 17 and 18 and the printing mechanism 2, respectively. The density measuring device which is one of these two density measuring devices 19, and which is in front of the excluded sheet redirection devices 17, 18 can of course be eliminated or completely removed from the machine. Can be done. However, only a single densitometer can be used for a reasonable overall cost reduction, which is removably fixed in the machine and in each case the last one-sided printing area (1 or 2) and the following direction change devices 17 and 18 are fixed. FIG. 3 shows an optional cylinder 20 of the printing press, near which is mounted a density measuring device 16 to 19 which extends laterally over the entire cylinder width.
It consists of a densitometer bridge 21 which is detachably mounted in the machine both mechanically and electrically and which, for each individual width region of the sheet, is simply short. It holds a densitometer 22 shown as a line. FIG. 1 shows the density measuring device for one-sided printing next to the pressure cylinder after the last one-sided printing area.
And, instead of the arrangement shown in FIG. 2, the density measuring device can also be arranged on the cylinder of the next sheet redirection device outside the one-sided printing side of the sheet, depending on the structural characteristics of the printing press. . However, it is also possible to arrange the cylinders of the sheet transfer devices 12, 13, 14 between the back printing-printing area of the density measuring device 19 for one-sided printing (here the one-sided printing side is on the outside). This possibility does not only result in no penalty for monitoring the color density (Farbdensitat) of the one-sided press, but rather, it automatically imposes a certain influence on the side of the one-sided print in the back-printing area of the printing press. This has the advantage that it is considered together when monitoring the printing side. As described, individual area-densitometers (Zonen-
The densitometer 22 can also be mounted on at least two or more bridges, both the area-densitometer for the one-sided printing side and the area-densitometer for the back-sided printing side of each stamp sheet. Each bridge is mounted on one or more press cylinders, each of which has one side or the other side of the printed sheet to be inspected facing outward. This is because the individually controllable width areas are selected narrow, so that all of the width areas and all of the printed color checks in the machine are in line due to the structural width of the thermometer, i.e. , When they cannot be attached to a common bridge.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows, in a side view, the main parts of a multicolor printing press having six printing mechanisms and one sheet direction changer. FIG. 2 also shows a printing press having six printing mechanisms, but having two sheet redirection devices, each of which can be selectively switched from a transport operation to a redirection operation. it can. FIG. 3 shows the mounting of individual zones (Zonen) -densitometers or individual zones of a full color tester-color tester on a common bridge near the cylinder of the printing press. [Description of Signs] 1 Printing mechanism 7 Sheet feeding device 11 Pressure cylinder 16 Density measurement Measurement 17 Body (direction changing device)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B41F 33/00-33/14 B41F 31/02

Claims (1)

(57) [Claims] Multiple printing mechanisms and two printing presses to convert from simplex to reverse printing
In the color area of the sheet, to adjust the sheet direction changing device between the frame and the color to be supplied
A color or color density measuring device for detecting color printing,
Multicolor sheet printing machine for one side and back side printing
A first color or color density measurement device for one-sided printing
A second color or color density measurement device for printing, wherein the first color or color density measurement device is printed in one-sided printing.
The installation position can be changed according to the number of colors to be printed, and the first color or color density measuring device is printed in one-sided printing.
Between the printing mechanism that prints the last color and the next printing mechanism.
Installed, a second color or color density measurement device downstream of the last printing mechanism
A multicolor sheet printing machine characterized by being provided in a multicolor sheet printing machine.