DE7518920U - DEVICE FOR ADJUSTING PRINTING PLATES ON THE PLATE CYLINDER OF PRINTING MACHINES BY MEANS OF A READING DEVICE AND FITTING CROSSES COPIED IN ON THE PRINTING PLATES - Google Patents

Description

ROLAND Offaetmaachinenfabrik Fabar & Sehlaioher AG 605 Offenbach am Main

Device for adjusting printing plates the plate cylinder of printing machines with the help a reading device and on the printing plates einkooierten_Paßkreuzan

With offset machines that use several colors in a row or to print in one pass of a sheet, it is necessary that for each color to be printed one soparate Pressure plate is available. In order for all the colors on the printed sheet to be exactly one above the other in multicolor printing, it is necessary that all the printing plates; are congruent on top of each other. This aligning is until now one more work that takes a relatively long time saying takes and a high level of skill at the Printer provides, because after a test print is made the printer must check this and any existing passport errors by setting the printing *. ' correct plates. |

It is known that check-in on the plate cylinder holders X

who have the task to open a plug-in magnifying glass

take with which the printing plate towards the plate cylinder a

can be aligned (DT-OS 2 261 084). Where |

it is necessary that the magnifying glasses are in their holder |

and on a marking on the plate |

cylinder can be adjusted. Then the magnifying glasses are removed |

taken and the printing plate pulled onto the plate cylinder g · - ^r. Then the already set magnifying glasses are attached again and the printing plates are aligned with the magnifying glasses. Before starting the machine, the magnifying glasses must be removed again

- 2nd

The invention is based on the object of creating a device BU which shortens and simplifies the setting up of the printing plates and also during the Operation can remain on the machine

According to the invention, the object is achieved in that aa plate cylinder outside the printing area in a fixed position a zero mark is provided, One discharge device each on the inside widths of the The side stand is displaceable and can therefore be brought into a certain position relative to the zero mark, and the The difference between the zero mark and the registration marks on the printing plate can be read.

The advantage of the invention is that sjan the The plate cylinder with the registration marks or the zero marks only moves approximately exactly into the viewing area of the reading device (- 1-2 mm) and then by following the Reading device sets the exact position of the reading device to the pass mark or to the zero mark. Because of this construction, the reading device can also remain on the machine when it is in operation. The difference determined by the reading device enables the pressure plate to be adjusted quickly and precisely. For some work it is advantageous to also make the zero marks adjustable.

Another variant of the invention is that the zero mark outside the printing area with the matching marks on the printing plate by means of a combined optically electronic Depositing device is scanned and the resulting difference is passed to a central control unit, which displays the value of the difference or ala Forwards the control impulse to the machine control

Exemplary embodiments are further described on the basis of the following drawings. Bs shows:

Fig. 1 shows a plate cylinder 1 with the

device according to the invention attached on both sides,

Fig. 2 shows an end of the plate cylinder with the holder and adjusting device the device,

Fig. 3 the magnifying glass k with the scaled ground glass 7 and

FIG. K shows the reading device with the symbolically represented optically electronic transmitter and receiver unit 11a and 11b.

On the plate cylinder 1 outside of the printing surface on both sides βληβ is provided in their position zero mark 2, which marks the start of printing. By means of an attached to the inside of the side stand and in Circumferential direction to the plate cylinder 1 pivotable reading device 3 is the difference between zero mark 2 and the registration marks 5 on the printing plate 6 readable.

The measurement of the difference is done by adjusting the Ablas evorrichtung 3 with the scaled ground glass 7 below the magnifying glass 4 on the registration mark 5 on the plate cylinder and compared with the superimposed zero mark 2. With the help of the scaled ground glass 7, the difference between the zero mark 2 and the pass mark 5 can be read off. Another possibility is to place the reading device with the scaled ground glass 7 over the PaB mark 5 on the pressure plate 6 and by means of a

ι t "is

• I · ·

• Micron tera screw 9 crouched down the depositing device 3 • ο to be adjusted far, see the reflected * zero mark 2 with the scale of the ground glass "7 previously set on the registration mark 5 of the printing plate 6. The The resulting difference can be read on the scale of the micrometer screw 9.

If the reading device is equipped with optically electronic transmitters and receivers, the Device can be constructed as follows: The reading device 3 is moved eo that the Registration mark 5 on the printing plate 6 with the scaled ground glass 7 covers. The reading device is then over a micrometer screw 9 ″ with a sliding resistance Io is provided, shifted so far in the circumferential direction until the optically electronic transmitter and receiver unit 11a / 11b covers the zero mark 2 outside the printing area. The resulting displacement is made visible via an electronic display or it is passed on to the machine control system as a control pulse. The now visible difference can be readjusted manually by the printer on the circumference register or from the machine control a remotely controllable circumferential register can be passed on, which automatically compensates for the difference.

Claims (1)

• · Protection claims 1.) Device for adjusting printing plates on the plate cylinder of printing machines with the help of a reading device and register marks copied onto the printing plates,
characterized in that a) a zero mark on the plate cylinder (1) outside the printing area in a fixed position (2) is provided and b) one reading device (3) each slidable on the inside of the side stand and so that it can be brought into a certain position relative to the zero mark (2) the difference between the zero mark (2) and the pass marks (5) of the printing plate (6) in the reading device (3) is visible. jf 2.) Device according to claim 1, dadu-ch marked that f a) a magnifying glass (4) in the reading device (3) is brought, which has a ground glass (7) with an incised line on its underside, b) the zero mark (2) can be displayed in the beam path of the magnifying glass (4), ί c) the reading device (3) has a lighting unit has the registration marks (5) on the printing plate (6) and the zero mark (2) on the plate cylinder (1) illuminated in such a way that the difference between the zero mark (?) And the registration mark (5) of the printing plate (6) is visible on a scale on the focusing screen (7). ι · · * 9 9 tt λ mm · · 4 ι · · · ■ · «· 3.) Device according to claim 1, characterized in that the reading device (3) by a micrometer screw (9) adjustable and its adjustment is visible. 4.) Device according to claim 1-3, characterized in that a) the reading device (3) is provided with a magnifying glass (4) and a ground glass (7) with a scale is, b) an optically ectronic one in the reading device (3) Transmitter and receiver unit (11a, 11b) is available, c) a sliding resistance on the micrometer screw (9) (10) is attached.