Patent Application
20080017060
The sole FIGURE illustrates a flow chart of a preferred embodiment of the method according to the invention with various further developments.
In the preferred embodiment described herein, an RFID chip is attached to or integrated into a pallet of a pile of paper sheets to be processed in a printing press, in particular an offset printing press. An RFID chip integrated in a pallet of a paper pile may be written on and/or read in a touch-free wireless way. Information about the paper and the job are stored on the RFID chip in a touch-free way. The producer of the paper may be the first to write information about the paper, in particular the properties of the material, onto the RFID chip. Alternatively, the paper may be re-stacked onto specially equipped pallets in the print shop and the associated information about the paper may then be written onto the RFID chip. Re-stacking is a common feature in print shops with special logistics systems, so that this additional feature of the invention does not require any disadvantageous additional work. As an alternative to receiving an integrated RFID chip in the pallet, an RFID chip may be attached to a conventional pallet (that may or may not carry paper) in the form of a sticker or mechanically, for example by stapling. At the feeder of the printing press, this information will be read into the control unit of the printing press, so that the control unit may check whether the paper is suited for the current print job and may preset the printing press.
In the delivery, processed paper sheets are deposited in a pile on a pallet that includes an RFID chip. As mentioned above, a pallet with an integrated RFID chip or a conventional pallet to which an RFID chip has been attached, in particular by an operator, may be used. Data on the properties of the printed paper sheets, in particular which sheets in the deposit pile are defective, are stored in a touch-free manner on the RFID chip. In further processing steps in a further processing machine, in particular in a die-cutter or a folding machine, the defective products may be removed.
Referring now to the sole FIGURE of the drawing in more detail, there is shown a flow chart of a preferred embodiment of the method of the invention with various further developments of a workflow in the production of print media.
The RFID chip of a paper pile, which is received on a pallet, is read out in the feeder of a sheet-fed offset printing press, so that information on the properties of the material of the paper may be read into the control unit of the sheet-fed printing press. The workflow of the preferred embodiment of the method of the invention thus comprises a step 10 of reading in the properties of the printing material. As the reading and writing range of common RFID chips at the moment may be as much as a few meters, the pallet does not have to be aligned with particular precision in the feeder (nor in the delivery). The printing press reads the information about the paper as it is stored on the RFID chip, checks whether the paper is suited for the current job, and starts presetting.
Defective products are created during printing for different reasons. In particular, the operator must adjust the press before acceptable sheets are printed. In other words, all sheets up to a first sheet that meets the requirements (acceptable sheet) are defective products. In addition, defective products are created when the machine is stopped and restarted (start-up waste), when the press speed is changed (for example because the printing units are no longer in register when the speed is changed), and when disruptions of the power supply occur.
In a step 12, the defective products that have been created are identified. There are in particular two ways of establishing which part or parts of the production are defective and which part or parts are not. On the one hand, the operator may input into the control of the press which printed sheets are to be counted as defective and which are not. On the other hand, an automatic inspection of the sheets, in particular an optical evaluation of the printed image, may take place to identify individual sheets or a number of sheets as defective. In other words, the control unit may have an identifying value that may assume at least two states (one for defective products and one for acceptable sheets). The states can be switched, for example by input via a human/machine interface or by an automatic control. It is possible to determine whether individual blanks of a sheet with multiple blanks are unusable while other individual blanks of the same sheet may be usable because they meet the quality requirements in particular by evaluating the entire printed image.
In a step 14, the defective products are electronically marked. In the delivery of the printing press, the information about which sheets or blanks on a sheet with a number of blanks are defective is written onto the electronic storage medium, for example the RFID chip in the pallet of the delivery pile. Advantageously, as a result of the invention, the location of the defective products in the pile does not have to be marked, the defective products do not have to be optically marked themselves, and they do not have to be removed from the pile. Another non-negligible advantage of this embodiment including an RFID chip is that contaminations as they may occur in the delivery of a printing press for example due to powder dust, do not have any negative influence on the functioning of the method because a wireless or touch-free, non-optical way of data exchange between the control unit and electronic medium is used. In this embodiment, additional job data such as the job number and job data indicated in the JDF specification are stored on the RFID chip.
For correct further processing of the pile, the association of the information stored on the RFID chip with the individual sheets in the pile, which are in a certain order, must be maintained. This necessity in particular incurs that no operator may remove sheets from the pile or rearrange sheets in the pile without informing the relevant processing machine in the workflow or correcting the data on the RFID chip in a corresponding way. As a consequence, the device for removing samples in the delivery of the printing press is designed so that the removal of sheets is taken into account when the information is written on the RFID chip. Moreover, the delivery has an input device for the printer to input the number of the removed sheets and other information required for identifying the defective products and/or the order of the sheets in the pile to make this information available to the control unit of the printing press.
In a step 16, the sheet pile including at least some defective sheets and the RFID chip that has been written on are transported together to a further processing device, for example a die-cutter. In this way, both the printed sheets to be processed and the relevant values of processing parameters associated therewith are jointly supplied to the further processing machine in a correlated manner.
In a step 18, values of processing parameters are transferred to the further processing machine by means of the RFID chip so that the defective products are taken into account during further processing. The control unit of the further processing machine, in this case the die-cutter, reads the information stored on the RFID chip so that the further processing machine may be set accordingly and/or may react in an appropriate way to every individual sheet to be processed.
It is to be noted here that if the described further processing operation is only a first further processing operation such as cutting, printing a special or spot color, or varnishing in a special machine, additional defective products may be created. For subsequent further processing operations, the information about these defective products is stored on a RFID chip in an analogous way in addition to the remaining other relevant information. In other words, the method of the invention may be iterated for a number of successive processing operations.
In a step 20, the defective products are removed. According to the invention, the removal of the defective products present in a pile of sheets takes place in a processing step of the printed product in which removal is easy. In the case of a die-cutter, the defective products may be disposed of in the container for the cutting waste. It is even possible to remove individual defective blanks by means of a removal device and to dispose of them in the container while acceptable blanks continue to be processed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2006 033 365.9 | Jul 2006 | DE | national |
