JPH0712240U - Printer - Google Patents

Abstract

(57) [Summary] [Purpose] To facilitate inspection. [Structure] After the last one-side printing / one-printing area, the one-side printing side of each sheet is arranged in the cylinder of the whole machine, and the density measuring device or other color test for controlling the back-side printing is arranged. The container is located after the last backside printing area of the machine.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The invention provides a simplex printing system comprising a number of printing mechanisms and at least one sheet orientation changing device for switching from single-sided printing to single-sided and backside printing, between two printing mechanisms each. The present invention relates to a multicolor sheet printing machine for one-sided and backside printing.

[0002]

[Prior art and its problems]

 In recent developments in multicolor printing, density measuring devices or other color testers have been provided for different width areas of the printed sheet (Breitenzonen), which are used to provide a pre-determined standard for the actual print. Continuous monitoring of the agreement of the color densities of the various colors in the individual width areas between the values is carried out. If a pre-given color tolerance is exceeded with respect to the desired standard value, an alarm indication is generated, which indicates to the operator the need for adjustment of the inking device in one or more of the width areas, or Or immediately readjust the ink supply to the relevant width area in a closed loop. For simplicity, only the densitometer will be described below. However, all other types of color testers can be used instead.

Printing presses, in particular offset-sheet presses with multiple printing mechanism units, each including an inking device and multiple cylinders, have been hitherto specifically used for multicolor printing presses. In order to control the color density (Farbdensitaet), the printed sheet is taken out from the sheet storage (Bogenablage), and the color density at various positions of the color density-measuring stripes (meβstreiben) printed together is measured. When the measured deviations from the given color densities occur, both in the transverse direction of the printed sheet and for the individual colors, the individual inking devices are placed in the adjusting device acting on the ink blade. I needed to make adjustments. This method of operation requires constant monitoring of the prints. This method of operation is time consuming, interferes with the continuous printing process and cannot prevent the production of large amounts of waste.

Known attempts to eliminate this problem have been to measure the color density of the color test area of the print in at least one cylinder adjacent to the outward-facing, at least partially printed surface. There is an adjusting device with standard value presetting (Soll-Vorgabe) in this case, and the inking device or inking devices are equipped with a control element (Stellgliede). ), Which is activated by the control output of the adjusting device. In this known solution, a densitometer is arranged in the measuring cylinder, which is arranged between the transfer cylinder of the last printing mechanism unit and the sheet feeder (Bogea sleger). The proposal is realized in that each printing mechanism unit is equipped with a density measuring device, which is arranged in an intermediate cylinder which directly connects to the printing mechanism unit. However, in fact, this known solution requires two additional cylinders each to reach the cylinder, where the printed side is on the outside and to which the concentration measuring device can be attached. it can. In this format, it is possible to switch from one-sided printing to one-sided and back-sided printing, and vice versa.In a multicolor sheet printing machine, when adjusting one-sided and back-sided printing, it is not necessary to control various color densities on both sides of the sheet. Or, it can't be implemented unless there are other measures.

Therefore, the object of the present invention is based on printing a multi-color printing machine that can switch from one-sided printing to one-sided and back-sided printing, in which the user does not Regardless of how it is adjusted, it is possible to continuously inspect the color density when printing on the front and back sides, and at the lowest possible cost (number) of the density measuring device. In this case it must be taken into account that such a density test on both sides of the sheet can be carried out at any possible adjustment of the machine. For example, in a multi-color sheet printing machine in which many sheet transport devices are located between individual printing mechanisms or printing areas, for example, in the case where the printing machine operator (Betreiber) has a total of five printing mechanisms. 1 color for 1 sided printing, 4 colors for backside printing, 2 colors for 1 sided printing, 3 colors for backside printing, 3 colors for 1 sided printing and 2 colors for backside printing, or 4 colors for 1 sided printing Depending on whether you want to print on the press and one color on the back side, and optionally on five sides, on one side, one sheet transport device at one time and another sheet transport device at another time It is conceivable that can be used as a sheet direction changing device.

[0006]

[Means for solving problems]

 For this purpose, according to the invention, a density measuring device or other color tester for the control of one-sided printing is provided in the cylinder of the entire machine after the last one-sided printing and one printing area in the sheet running direction (here The front side of the sheet is on the outside) and a densitometer or other color tester for controlling the backside is placed after the last backside printing area of the machine. Will be solved.

In such an arrangement, each sheet can be checked for density on both sides or on one side or on the back side at the lowest possible cost, yet continuously and on one side and one back side. It can also be checked during each arbitrary adjustment of the process.

The present invention can be implemented by various means. For example, it is also possible to mount a density measuring device for one-sided printing on the last printing cylinder after the last one-sided printing and one printing area and before the next sheet one-direction diverting device, respectively. However, it is also possible to place this density measuring device for one-sided printing in the cylinder of the sheet redirection device after the last one-sided one-sided printing area (here the one-sided printing side is outside). . In addition, the density measuring device for one-sided printing may be installed in the cylinder of the sheet transfer device between the backside printing and one printing area, or in the cylinder after the last backside printing and one printing area. It can also be located (outside).

In yet another configuration of the present invention, it is reasonable for the individual densitometers of the densitometer to be mounted on a common Bruecke, which are removable and replaceable. It is fixed in the printing machine. It is necessary in printing presses with many redirectors (in this case, of course, only one sheet redirector always works), which requires only one density measuring device, which can be located in different places in the press. It can be fixed, i.e. fixed in front of each effective sheet turning device. In this way the cost of the densitometer or color tester is particularly reduced.

If the width area of the sheet to be inspected for color density is made very narrow for reasons of high accuracy, even with a densitometer or other color tester, even a densitometer for single-sided printing, Even with densitometers for backside printing, it may happen that they cannot be mounted side by side on a common bridge. Therefore, for this case, according to the invention, it can be mounted on one or many cylinders of the entire printing machine, here either on the one-sided printing side or on the back-sided side of the sheet to be inspected, respectively. Proposed. In this case, the densitometer can be divided into two bridges by different colors to which the individual densitometers respond, eg if two bridges are provided for their attachment, or one bridge To hold densitometers for the first, third, fifth, etc. width areas of the sheet, and other bridges to hold densitometers for the second, fourth, sixth, etc. width areas of the sheet. You can also

The invention will be described in detail below by means of embodiments schematically illustrated in the drawings.

[0012]

【Example】

 The printing mechanism is shown in succession from 1 to 6 in FIGS. It is represented by the 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 machine according to FIG. 1 has six printing mechanisms 1 to 6 and relates to a six-color printing machine. The sheet feeder is shown at 7 and the sheet feeder is shown at 8. Each printing mechanism has a printing plate cylinder 9, a rubber cylinder 10 and a pressure cylinder 11, which cylinders are provided with reference characters only for the printing mechanism 1. Between the two printing mechanisms 1 and 2 is a Ubergabe device comprising a small cylinder 12, 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 blackened to distinguish them from pure sheet transfer machine cylinders. If the sheet diverting devices 17, 18 are intended for pure sheet transport, the whole machine operates in 6-color single-sided printing, so only one density measuring device 16 is required after the last printing machine 6. The reason for this is that only the surface of the sheet is printed in 6-color printing. On the other hand, if the sheet turning devices 17, 18 are switched to single-sided and back-printing, then another density measuring device 19 is required, which is the last one with the sheet turning devices 17, 18. ) Between printing areas, that is, in the printing area of the printing mechanism 2. The sheet is now printed on one side in two-color-one-sided printing by the printing mechanisms 1 and 2 and in four-color backing in the printing mechanisms 3 to 6, in which case this first two-color printing is performed by the density measuring device 19 , And the four-color press on the other side of the sheet is controlled by the densitometer 16.

FIG. 2 likewise shows a 6-color printing press with 6 printing mechanisms 1 to 6. This machine has two sheet redirectors 17, 18, one between the printing mechanisms 1 and 2 and the other between the printing mechanisms 2 and 3. If both sheet redirectors 17, 18 are excluded, the machine operates in 6 colors-one sided printing. If only the sheet redirecting device 17, 18 is inserted between the printing mechanisms 1 and 2 (einschalten), the sheet redirecting device between the printing mechanisms 2 and 3 is excluded in the opposite (ansschalten). The machine operates in one color, one side and five colors-back side. On the other hand, when the printing mechanism includes only the left of the sheet direction changer 17, 18 between 2 and 3, and the preceding direction changer between the print mechanisms 1 and 2 is excluded, The machine operates in two-color one-sided printing and four-color backside printing. In this machine, in addition to the density measuring device 16 after the last printing mechanism 6, between the printing mechanism and the sheet diverting device 17, 18 which first arrives on the one hand in the sheet running direction, and the second sheet diverting device. Another density measuring device 19 is provided between each of the devices 17 and 18 and the printing mechanism 2. The density measuring device which is one of these two density measuring devices 19 and in front of the excluded sheet turning device 17, 18 can, of course, also be excluded or completely removed from the machine. Can be done. However, only one densitometer can be used for a reasonable total cost reduction, which is removably fixed in the machine and is the last single-sided printing area in the press. It is fixed between (1 or 2) and the next direction changing device 17, 18.

FIG. 3 shows an optional cylinder 20 of the printing machine, in the vicinity of which density measuring devices 16 to 19 are mounted which extend laterally over the entire cylinder width. It comprises a densitometer bridge 21, which is mechanically and electrically removably mounted in the machine and is individually short for each individual width region of the sheet. Holds a densitometer 22 shown as a line.

Instead of the arrangement shown in FIGS. 1 and 2 in which the density measuring device for one-sided printing is located by the pressure cylinder after the last one-sided printing area, this density measuring device is It can also be placed in the cylinder of the next sheet redirection device on the outside of the single side of the sheet. However, it is also possible to arrange it in the cylinder of the sheet transfer device 12, 13, 14 located between the back surface printing area and the printing area of the density measuring device 19 for the one-sided printing (here, the one-sided printing side is outside). . This possibility does not lead to any disadvantage in monitoring the color density of the one-sided printing (Farbdensitat), but rather it allows the one-sided printing side to automatically have a certain effect on the side of the one-sided printing within the backside area of the printing press. It has the advantage that it is considered together when monitoring the printing side.

As mentioned, the individual zone-densitometers 22 are used both for the printing side of one side of the printing sheet, the densitometer for the back side of the printing sheet, and the densitometer for the back side of the printing sheet. It can be mounted on at least two or more bridges, each of which is mounted on one or many press cylinders, each of which is on one side of the printing sheet to be inspected. Or, the back side is on the outside. This is because the individually controllable width areas have been chosen to be narrow, so that for inspection of all width areas and of the colors printed in all machines all in line due to the constructional width of the thermometer, That is, it is suitable when it cannot be attached to a common bridge.

[Brief description of drawings]

1 shows a side view of the main part of a multicolor printing machine with six printing mechanisms and one sheet redirector.

FIG. 2 likewise shows a printing machine with six printing mechanisms, but with two sheet redirection devices, each of which can be selectively switched from transfer operation to redirection operation. it can.

FIG. 3 shows the mounting of individual zones-densitometers or individual zones of all color testers-color testers on a common bridge near the cylinder of the printing press.

[Explanation of symbols]

 1 Printing Mechanism 7 Sheet Supply Device 11 Pressure Cylinder 16 Density Measurement Measurement 17 Cylinder (Direction Changer)

Claims (6)

[Scope of utility model registration request] 1. A multi-printing mechanism and at least one printing mechanism between two printing mechanisms, each of which has a sheet direction changing device capable of switching from one-sided printing to one-sided and back-sided printing, and various sheets. Have a densitometer or other color tester for the width of the area of interest, which will give an alarm indication when they deviate from the desired standard value of the area concerned or of the area concerned in closed loop. In a multi-color sheet printing machine for one-sided printing and one-sided and back-sided printing for readjustment of ink supply, a density measuring device (19) or other color tester for controlling one-sided printing is the last in the sheet running direction. Density measuring device (16) for controlling the back side printing, where the one side printing side of each sheet is placed outside the cylinder of the whole machine after the one side printing side printing area The printing machine, characterized in that the other colors tester is placed after the last backside printing one print area of the machine. 2. The density measuring device for single-sided printing (1
2. A printing machine as claimed in claim 1, wherein 9) is mounted on the last pressure cylinder (11) after the last one-side-on-one printing and thus in front of the next redirecting device (17, 18). 3. A density measuring device (1) for one-sided printing.
2. A printing machine according to claim 1, wherein 9) is arranged in the cylinder of the sheet redirecting device (17, 18) after the last single-sided single-printing area (where the single-sided printing side is outside). . 4. The density measuring device (1) for one-sided printing
9) is a sheet delivering device (1
2. The printing machine according to claim 1, which is arranged in a cylinder (here the front side of each sheet is on the outside) after the last back side printing area. 5. An individual area of the densitometer-densitometer (2
2) to the individual area of the full-color tester (16, 19) -the color tester being removable and replaceably mounted on a common bridge (21) fixed in the press. The printing press according to any one of 1 to 4. 6. The individual area-densitometer (22) of the densitometer or the individual area-color tester of the full color tester (16, 19) is mounted on at least two bridges (22). And said bridges (22) are attached to one or a plurality of cylinders of the printing machine (here the printing sheet to be inspected is on the one-sided printing side or the back-sided side, respectively), which are preferably 5. A printing press as claimed in any one of the preceding claims, wherein the printing press is detachably and replaceably fixed in the printing press.