This invention relates to a device and process for handling printed sheets leaving digital sheet printers, able to be directly connected in line with the printer to obtain an integrated system for printing sheets of various formats containing several single-page or multiple-page documents, and their conversion into documents by cutting them transversely to the sheet movement direction and by other operations subsequent to the transverse cut.
The handling device and process are applicable both to digital sheet printers in which the paper moves from right to left in the printer and to digital sheet printers in which the paper moves from left to right in the printer.
In the state of the art, those offices and departments using industrial digital printers for sheets, for example for printing employee's pay-packets, print on sheets of A4 format which, after printing, are sorted, then stacked in vertical receivers and subsequently inserted into a machine for envelope filling or for binding.
Currently, the printing cost is dependent not on the size of the printed sheet but on their number, hence for those offices which process large document quantities, the total printing costs are proportional to the quantity of sheets handled by the printers.
It is very common to use industrial digital sheet printers to print documents consisting of several A4 sheets with sheet quantities variable between one document and the next in their printing sequence. Whatever their format, the printed sheets are commonly collected in receivers which stack the sheets vertically by laying them extended one on another. In order not to interrupt the printing process, when a first vertical receiver is full the A4 sheets are fed to a second vertical receiver via a bypass device of the first vertical receiver.
With current printing programs commonly used for printers, it is never possible to ensure that all the documents of variable sheet quantities are completely collected in the first vertical receiver, so that it can happen that a document has part of its sheets collected in the top of the pile of the first vertical receiver and part of its sheets in the bottom of the pile of the second receiver.
For subsequent post-print handling of the documents, whether envelope filling or binding, the documents have to be worked while maintaining them in the sequence in which they were printed.
If the machines used for envelope filling or binding were to handle the piles of sheets of the vertically collected documents as extracted by the printers which withdraw the sheets from the top of the pile, the document printing sequence would be altered and there would be the risk of not being able to complete document processing where part of the sheets have finished at the bottom of the first row of the first vertical receiver and the remaining sheets of the same document have finished at the bottom of the pile of the next vertical receiver.
The solution universally used consists of manually unloading the sheets from the various vertical receivers of the printers, taking care that the document print sequence is maintained when loading the sheets onto the sheet feeders of the envelope or binding machines. This manual procedure implies risks of error in the post-print processing stages besides a general productivity loss in the entire document processing, printing and distribution procedure.
With usual print cost debiting mechanisms based on the “click charge” concept, the cost of printing an A3 sheet is the same as the cost of printing an A4 sheet, hence the user of digital printers for sheets could print A4 page documents on A3 sheets, collect them in the usually used vertical receivers and, before passing to subsequent envelope filling or binding, divide the pile of A3 sheets into two piles of A4 sheets using industrial guillotines. However this procedure would not be practicable because all control over the sheet sequence in the documents would be completely lost.
Similar considerations also apply to sheet formats other than A4 and A3.
An object of the present invention is therefore to provide a device and process which overcome the aforesaid drawbacks.
A particular object is to reduce the print costs and times by printing documents on A3 sheets, forming coherent A4 documents by cutting each A3 sheet along its short side, and collecting the documents in A4 format.
A further object is to simplify the feed of sheets to the envelope or binding machine by providing a process for collecting A4 documents on horizontal receivers insertable into the printing machine, which maintain the sheets in a vertical position and in the correct print sequence even if the collection of a document print flow is divided between two or more horizontal receivers.
A further object of the invention is to provide a device connectable directly to digital sheet printers upstream and to other devices and/or machines downstream of the device itself, to allow post-print operations and processes which are very flexible while at the same time enabling the digital printers to totally utilize their printing versatility towards a plurality of applications in the most varied sectors in which digital printing is used.
In particular, according to the invention the sheets being handled (of A3 or other than A3 format) can be cut in various ways for their conversion into documents (of A4 or other than A4 format) or the cutting step can be bypassed and the documents (i.e. the cut sheets) be collected differently according to specific requirements.
Another object of the invention is to provide a device and process adaptable to the downstream processes and machines.
For example, according to the invention the documents are collected in piles, the flow of these document piles being adaptable to the characteristics of the printer (which for example may not be able to accommodate frequent successive stoppages and starts) and/or to the specific needs of the downstream machines or processes which, for example, may require the sheets to be fed in a specific direction or in a predetermined manner.
These and further objects are attained according to the present invention by a device and process in accordance with the accompanying claims.
The reference to A3 and A4 formats is given by way of example only, similar considerations and advantages also applying to formats other than A3 and A4.
Further characteristics and advantages of the invention will be more apparent from the ensuing description of a preferred but non-exclusive embodiment of the device and process of the invention, illustrated by way of non-limiting example in the accompanying drawings, in which:
Current printers are controlled electronically and can print on either A4 sheets or A3 sheets, distributing the print on the sheets in the manner desired by the user.
In an alternative configuration the sheets can be stacked horizontally by resting them one on the other on their faces.
The sheet handling device of the invention operates connected directly to the digital sheet printer, i.e. the printed sheets are directly fed to the device and handled in such a manner as to obtain a single process from printing to the finished document, i.e. without continuous production of complex documents.
The same control member 3 is able to feed the sheets cut into A4 format to two interceptor and receiver devices 8 and 9 should any irregularities occur while printing the sheets or reducing the sheets from A3 format to A4 format. Depending on the requirements of the subsequent post-print process, the sheets converted into A4 format can be stacked vertically resting either on their short side or on their long side. The receivers comprise a sheet carrier belt and a movable wall ensuring that the sheets are compacted, hence enabling them to be stacked vertically on the horizontal receivers while maintaining the correct print sequence.
The text which is to be carried on two A4 sheets is printed on one A3 sheet, resulting in both a reduction in cost, which is calculated on the basis of the number of sheets printed independently of their dimensions, and a reduction in time due to the elimination of the time required for feeding a double quantity of A4 sheets to the printer.
The A3 sheet is then cut into two A4 parts by a cutting member 1 fed by a conveying member 2.
After the printing and cutting operation, the resultant A4 sheets are inserted into a control member 3, able to shift the sheets towards the right or left, to distribute them to suitable receivers 4 and 5. These horizontal receivers 4 and 5 in which the sheets are vertically stacked, are preferably of horizontal stacking type and present the characteristic of being removable and usable as loaders for envelope machines 6 or binding machines 7. This characteristic is particularly advantageous because it enables the sheets to be inserted into the envelope machines 6 and binding machines 7 in the order in which they were printed.
In these embodiments the device 10 comprises a printer connection module for transporting sheets 13 with registration 12, which receives said sheets 13 from an industrial digital sheet printer 14 and feeds them to a cutter 15 (for example of rectilinear blade and counter-blade type with electronically controlled reciprocating movement) which transversely cuts (at 90° to the direction in which the sheets originating from the printer move) the sheets 13 and generates two or more documents 13a, 13b (in this description the term “document” means any sheet part which is cut, such documents 13a, 13b being able to be combined to generate complex documents comprising a plurality of pages).
From the latter (cutter 15) the documents 13a, 13b are fed to a receiver 17 which receives them, stacks them while maintaining their print sequence and transfers them to a discharge device 18.
The receiver 17 stacks the documents 13a, 13b horizontally face to face and maintained in the sequence in which they were printed; this is shown in
The cutter 15 cuts the sheets 13 into two or more parts to form documents 13a, 13b of equal or different dimensions; in particular,
The documents can be stacked into a single pile 19 (
The documents 13a are all stacked into a first pile and the documents 13b are all stacked into a second pile or, alternatively, the documents 13a and 13b are all superposed into a single pile then, when this has reached the set limit, all the parts 13a, 13b are stacked into another pile.
The discharge device 18 is arranged to feed the document piles in a direction aligned to the direction in which the documents 13 advance during processing or, alternatively, in a direction inclined, preferably by 90°, to the direction in which they advance during processing; this is shown by the arrow F of
The device 10 comprises control means 21 interfaced with the printer 14 positioned upstream of the printer connection module for transport with registration 12; these control means 21 implement the offset function in the receiver 17 as shown in
The piles of superposed documents 13a, 13b can also be fed automatically to a finishing machine 20 to implement an automatic document forming system which starting with blank or pre-printed documents enables printed documents possibly composed of several bound pages to be obtained.
In this case a conveyor is preferably provided downstream of the device 10 (after cutting by the cutter 15) to feed an automatic booklet former of type CEM series CSG (
The device 10 can also comprise a trimming device 23 with one or more pairs of circular blades, to longitudinally trim the documents 13a, 13b already cut by the cutter 15; this trimming device 23 is interposed between the cutter 15 and the receiver 17.
Advantageously the device 10 comprises a longitudinal cutting device 25 for example of circular blade type, to cut the documents 13a, 13b along a longitudinal direction (in the direction in which the sheets move through the printer); the longitudinal cutting device 25 is also positioned between the cutter 15 and the receiver 17.
Advantageously, this embodiment of the device enables a continuous sheet flow to be achieved from the printer to the finishing devices by uninterruptedly forming packs of sheets and distributing them. These sheet packs are directed in the direction in which the paper flows or in a direction perpendicular thereto.
This embodiment is particularly suitable for satisfying book-on-demand requirements.
A member for intercepting and discarding defective sheets is also suitably provided (not shown), to ensure the quality of the documents produced; this device is of a type known to the expert of the art. The member is integrated into the device 10 and is positioned between the exit of the cutter 15 and the receiver 17 and comprises an intermediate collection station enabling the converted documents to be accumulated during pile discharge and offset in order not to have to temporarily halt the printer, hence allowing uninterrupted operation.
The control means 21 control the device operation and are arranged to implement bypassing of the cutter 15, to enable the sheets 13 to pass through the cutter without being cut into parts of smaller dimensions and hence be fed to the downstream processing unit without being stacked, by an additional conveyor device. Alternatively these uncut sheets can be fed to the stacking system by the already described methods.
The control means 21 enable the device to receive commands from the printer 14 and to feed the printer with data enabling the device and printer to operate in a coherent manner, including the error situations which can arise in both machines. The control means 21 can also be provided with systems for sensing control codes printed on the sheets by the printer to enable control and/or mechanical operations on the documents to be carried out.
With particular reference to those embodiments of the invention shown in
The printer 14 prints the desired information on the sheets 13.
For example the sheets are of A3 dimensions, the information being printed (by the digital sheet printer) on each half of the A3 sheet.
The sheets 13 are then fed, by the printer connection module for transport with registration 12, to the cutter 15 which transversely cuts the A3 sheets into two A4 sheets which are stacked by the receiver 17.
Stacking can take place by one of the previously indicated methods.
If the documents have to be further cut (for example to form documents of A5 size) the longitudinal cutting device 25 is also operated and the documents 13a, 13b are further cut longitudinally to obtain documents of the desired format.
The documents must be correctly printed on the sheet 13 fed to the printer, the subsequent cutting steps then separating each document from the others printed on the same sheet; this operation is executed flexibly and rapidly by the device of the invention.
The present invention also relates to a sheet handling process consisting of cutting the sheets 13 to separate documents 13a, 13b, collecting the cut documents 13a, 13b and stacking them to form the finished document.
In particular, the following steps are performed:
In a particular embodiment of the process of the invention, the following steps are also provided:
Preferably, according to the invention the documents 13a, 13b are collected by stacking them horizontally face to face while maintaining the print sequence, with continuous production of complex documents.
The sheets are divided into two or more documents of equal or different dimensions and are stacked into a number of piles.
In a first example of the process, after cutting, each of the documents 13a, 13b is stacked on a different pile. Thus enables reduced dimension documents to be printed, such as cheques or other documents, on sheets which can contain two columns of them, each column containing multiple names. By means of the invention two document piles are created, one for each of the two print columns, the documents of each pile being grouped on the basis of identical multiple names by the offset function, ready to pass to the subsequent post-print operations. A typical example is the processing of cheques or other documents to be formed into booklets by finishing machines not integrated with printers.
In another example, after cutting, all the documents 13a, 13b are stacked onto one and the same pile.
When necessary, as shown in
According to the process the cutting step can be bypassed, to obtain at discharge not only documents with smaller dimensions than those of the initial sheets because they have been converted into documents of the required dimensions, but also documents with the initial dimensions.
According to the invention the stacking operation can also be bypassed, both for sheets on which the conversion cut is not made and also for documents resulting from conversion by single or multiple cutting of the printed sheets. This enables sheets or documents to be fed to other post-print handling systems integrated with the printer while maintaining the device of the invention interposed and operating, ready at any moment to easily pass to other applications for which its main functions are required. The conversion cutting bypass and the stacking bypass functions, if associated with a configuration of the conveying device by which the document piles are conveyed in a direction at 90° to the paper flow, give an exceptional degree of flexibility and versatility to an automatic post-print finishing system completely integrated with the printers.
In this respect, a plurality of documents 31, 32, 33, 34, 35, 36 are printed on a single sheet 30 (
The transverse cuts 37 (
Finally the documents 31-36 are superposed on each other (
This is achieved by transferring the individual documents 31-36 from left to right or from right to left, according to the print sequence, to mutually superpose them in their exact print sequence by a known device of the type described in IT 1 244 770.
In this manner piles can be formed consisting of a single complex document (book or volume), to satisfy the book-on-demand sector for one-off books.
This is particularly advantageous because the market tendency indicates that in the digital book printing sector the run make-up now tends towards a single example per run.
Advantageously, with the process of the present invention, runs subsequent to the first can be produced, each consisting of a single complex document (evidently, this is also true for the first run); in other words, those runs subsequent to the first (and also the first run) can comprise even a single volume or book.
In practice, printing is carried out such that the document J (i.e. page J) is superposed on the other documents to form the Jth document (i.e. the Jth page) of the complex document (i.e. the book or volume).
It has been found in practice that the device and process of the invention are particularly advantageous because they enable documents to be formed in a vary flexible and economically convenient manner, even for very small print runs.
The device and process conceived in this manner, although applicable to all digital sheet printers of industrial type of currently known handlable format and printing speed, are susceptible to numerous modifications and variants, all falling within the scope of the inventive concept; moreover all details can be replaced by technically equivalent elements.
In practice the materials used and the dimensions can be chosen at will according to requirements and to the state of the art.
Number | Date | Country | Kind |
---|---|---|---|
MI2004A 001540 | Jul 2004 | IT | national |
MI2006A 001355 | Jul 2006 | IT | national |
This application is a continuation-in-part of my co-pending application Ser. No. 11/189,813, filed Jul. 27, 2005.
Number | Date | Country | |
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Parent | 11189813 | Jul 2005 | US |
Child | 11594195 | Nov 2006 | US |