Abstract:
A method for processing a plurality of flat printed products is provided. The method includes the steps of determining one of at least two quality statuses for each flat printed product and for each flat printed product, storing a first information representing the determined quality status and a second information combining the first information with said flat printed product. The invention also relates to a corresponding device for processing flat printed products.

Description:
[0001]    Priority is hereby claimed to FR 10 54655 field on Jun. 11, 2010, the entire disclosure of which is hereby incorporated by reference herein. 
         [0002]    The present invention relates to a method for processing a plurality of flat printed products. 
       BACKGROUND OF THE INVENTION 
       [0003]    Known from the state of the art is a method in which an operator successively inspects the finished products, such as sections of a newspaper, printed using a printing press. The printed products that the operator considers to be of poor quality may be ejected and directed towards a bad copy outlet. The good copies are conveyed and stacked. The ejection is sometimes not very reliable and the possibility of the stack of good copies actually including bad ones as well cannot be dismissed. 
         [0004]    As a result, an unknown number of good quality printed products is combined with poor quality products and it is difficult to assess whether the production has already reached the necessary number of good quality copies. 
         [0005]    Another problem resulting from the prior art method is that the reliability of the inspection of the printed products depends on the operator and it is not guaranteed that all of the printed products stacked on the final pile will meet the quality requirements. This is all the more crucial when the production speed is high. 
         [0006]    In this way, the growth of the printing speed led to the design of printing presses that print on a substrate band that is successively cut into sheets. These sheets are then stacked at the outlet of the press. The speed of these printing presses is high enough that it is not feasible to direct the poor copies upstream of the press outlet. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    The present invention provides a method for processing flat printed products that allows them to be sorted effectively according to their quality. 
         [0008]    The present invention provides a method comprising the following steps of, for each flat printed product, determining one of at least two quality statuses, and for each flat printed product, storing a first information representing the determined quality status and a second information combining the first information with said flat printed product. 
         [0009]    According to other preferred embodiments, the method may include one or more of the following features:
       each flat printed product is a printed sheet;   the flat printed products are printed sections of a continuous band, in particular each section including the image of a page;   storing the first information and the second information in one or more storage means or a storage device;   stacking the flat printed products, without taking the first information into account, forming one or more piles;   the number of flat printed products stacked on each pile is measured continuously based on the height and/or weight of the stacked flat printed products;   the number of stacked flat printed products is counted continuously using a counter arranged upstream of each pile;   the step of stacking the flat printed products comprises stacking the flat products on at least one support, in particular a pallet;   the first information and the second information are grouped together per pile by forming a group of information and the or each pile is associated with the corresponding group of information;   the or each group of information is stored on a computer medium arranged on the support holding the pile with which the computer medium is associated;   for the or each pile and for the associated group of information, a reference information is created associating the group of information and the pile, and the reference information is stored together with the group of information as well as with the pile;   sorting stacked flat printed products according to the first information;   the quality status is determined using an inspection device comprising a detection device adapted to detect at least one feature of each flat printed product and a management device adapted to compare the at least one detected feature with a predetermined standard and to generate the first information based on the comparison;   the inspection device also comprises at least one totalizer, each totalizer being adapted to count, as a function of the first information representing a quality status, the number of flat printed products.       
 
         [0023]    The present invention also provides a device for processing flat printed products comprising an inspection device adapted to determine, for each flat printed product, one of at least two quality statuses, and one or more storage means or devices adapted to store, for each flat printed product, a first information representing the determined quality status and a second information associating the first information with the flat printed product, the processing device being adapted to implement a method as defined above. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0024]    The invention will be better understood upon reading the following description, provided solely as an example and done in reference to the appended drawing, in which the sole FIGURE is a diagrammatic view of a processing device according to the invention arranged at the outlet of a printing press with a cutter. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    The FIGURE shows a device for processing flat printed products, designated by general reference  5 . This processing device  5  is arranged at the outlet of a printing press  10 . 
         [0026]    The printing press  10  successively comprises an unwinder  15 , four printing units  20 , a traction device  25 , and a cutting device  30 . Nevertheless, the number of printing units  20  is not limited to four. The printing press  10  can comprise any number of printing units  20 . The unwinder  15  is adapted to unwind a continuous web or band  35  to be printed on which the printing units  20  print an image repeatedly. The traction device  25  is adapted to apply a predetermined mechanical tension on the continuous band  35  coming out of the printing unit  20  which is arranged the furthest downstream. The cutting device  30  is adapted to cut the continuous band  35  into a plurality of flat printed products  40 . Each flat printed product  40  is for example a printed sheet or a printed section of the continuous band  35 , each sheet and/or each section including the image of a page. A printing press of the aforementioned type is for example disclosed by French patent FR 2888527. 
         [0027]    The printing press  10  can also comprise a counter  42 . The number of flat printed products  40  leaving the printing press  10  is counted by the counter  42 . 
         [0028]    The processing device  5  comprises an inspection device  45  and one or more storage means or storage devices  50 . 
         [0029]    The inspection device  45  comprises a detection device  55  and a management device  60 . 
         [0030]    The detection device  55  is adapted to detect, for each flat printed product  40 , at least one printing quality feature. The detection device  55  is for example a CCD camera that generates an image showing the at least one printing quality feature. The at least one print quality feature is for example the superposition or the relative position of several print layers applied on the flat printed products  40 . Alternatively, one print quality feature is the optical density of the printed image. Also alternatively, the quality feature is the characteristic of the sheet (good/bad sheet). 
         [0031]    The management device  60  is connected to the detection device  55  using a first data line  62 . Information representing the at least one print quality feature is transmitted from the detection device  55  to the management device  60  via this first data line  62 . 
         [0032]    The management device  60  comprises a memory  64  and a processor  66 . The processor  66  is adapted to compare the information representing each print quality characteristic detected for each flat printed product  40  by the detection device  55  to a corresponding standard defined for each of the at least one feature, in order to evaluate the print quality of each flat printed product  40 . As a function of this comparison, the management device  60  attributes the print quality of each flat printed product  40  to one among at least two quality statuses. The processor  66  generates, for each flat printed product  40 , a first information  77  representing the determined quality status. The processor  66  also generates, for each flat printed product  40 , a second information  78  that associates the first information with the flat printed product  40  for which the first information  77  has been created. The second information  78  is for example a serial number of the associated flat printed product  40  or can be the location of the first information  77  in the storage device  50 . 
         [0033]    Alternatively, the inspection device  45  can be replaced by the operator himself. 
         [0034]    The or each corresponding standard is stored for the or each print quality characteristic, for example in the memory  64  of the management device  60 . If applicable, the or each standard can be stored elsewhere than in the memory  64  of the management device  60 , for example in an external memory. 
         [0035]    The storage device  50  is connected to the management device  60  of the inspection device  45  using a second data line  80 . The second data line  80  is adapted to transmit information, such as the aforementioned first information  77  and second information  78 , from the management device  60  to the storage device  50  and/or from the storage device  50  to the management device  60 . 
         [0036]    The storage device  50  is adapted to store, for each flat printed product  40 , the first information  77 . The storage device  50  is also adapted to store, for each flat printed product  40 , the second information  78  that associates the first information  77  with the flat printed product  40  for which the first information  77  was created. The first information  77  and second information  78  of a plurality of flat printed products  40  can be grouped together so as to form one or more groups of information  85  for the corresponding plurality of flat printed products  40 . 
         [0037]    After passage near the detection device  55 , the flat printed products  40  are stacked, independently of the first information  77 , forming one or more piles  87 . 
         [0038]    The processing device  5  also comprises at least one support  90  and at least one measuring means or measuring device  95 . 
         [0039]    The or each support  90  is adapted to receive the flat printed products  40  and to support the pile  87  thus formed. Preferably, a support  90  supports a single pile  87  of flat printed products  40 . The support  90  is for example a pallet. The aforementioned groups of information  85  can be formed so that for each pile  87  or support  90 , a group of information  85  is created. 
         [0040]    The or each measuring device  95  is adapted to determine, continuously or at predetermined intervals, the number of flat printed products  40  stacked on a pile  87  supported by a support  90 . Preferably, an individual measuring device  95  is associated with each support  90 . That means, preferably, one individual measuring device  95  is associated with each pile  87 . Such a determination of the number of stacked flat printed products  40  is done in that the or each measuring device  95  measures the height of the pile  87  and/or the weight of the pile  87 . In both cases, an individual calibration of the measuring device  95  is necessary for each production. Preferably, the calibration is done using a curve relating several values for the number of stacked flat printed products  40  with the weight or height of the corresponding piles  87 . 
         [0041]    The or each measuring device  95  is also adapted to detect whether part of the stacked flat printed products  40  is taken from the pile  87 , for example by a user. Based on the weight and/or height difference due to the withdrawal of flat printed products  40  and based on the calibration, the measuring device  95  determines the number of flat printed products  40  that have been taken from the pile  87 . 
         [0042]    The or each measuring device  95  is connected using a third data line  97  to the management device  60 . The third data line  97  is adapted to transmit, continuously or at a predetermined interval, information representing the number of flat printed products  40  stacked on a pile  87  determined using the respective measuring device  95 . 
         [0043]    Alternatively, the determination of the number of flat printed products  40  stacked on each pile  87  can be done by synchronizing the counter  42  of the printing press  10  with the management device  60 , the counter  42  being arranged upstream of each pile  87 . 
         [0044]    The processing device  5  also comprises at least one computer medium  100 . The or each computer medium  100  is adapted to store information. The computer medium  100  is for example a RFID label. Preferably, one computer medium  100  is associated with one support  90 . The computer medium  100  is for example fastened on the corresponding support  90 . The information stored by the computer medium  100  are for example the first information  77  and the second information  78  grouped together in information groups  85 , for the flat printed products  40  stacked on the associated support  90 . In this case, the computer medium  100  stores the same group of information  85  as the storage means  50 . This is shown in the FIGURE by a broken line  105 . The computer medium  100  and the storage device  50  can coexist, in order to store each group of information  85  locally and centrally, respectively. Alternatively, the computer media  100  of all of the supports  90  can replace the storage device  50  that stores the groups of information  85  for all of the piles  87  supported by all of the supports  90 . 
         [0045]    In one embodiment, the management device  60  combined with the detection device  55  serves as a totalizer adapted to count the flat printed products  40  as a function of the first information  77 . That means, in the event the first information  77  represents at least two quality statuses, this totalizer is adapted to individually count the number of flat printed products  40  for each quality status. 
         [0046]    Alternatively, the processing device  5  can comprise one or more additional individual totalizers  110 . 
         [0047]    Also alternatively, the processing device  5  is adapted to provide a report  115 . The report  115  is a summary of information for a production comprising direct information such as, for example:
       the total number of flat printed products  40 ,   the total number of flat printed products  40  for each quality status,   for each pile  87 , the number of flat printed products  40  for each quality status,   the first information  77  and second information  78  for each pile  87 ,
 
and indirect information, such as statistical information, which result from the direct information.
       
 
         [0052]    The processing device  5  described above is adapted to implement a method for processing a plurality of flat printed products  40  as follows. 
         [0053]    The flat printed products  40  leave the printing press  10  on a conveyor conveying them towards the support  90  on which the flat printed products  40  are stacked. During transportation between the printing press  10  and the stacking support  90 , each flat printed product  40  passes the detection device  55 , which detects, for each flat printed product  40 , the at least one print quality characteristic, and which creates an information representing the at least one detected feature. 
         [0054]    One example is the case where a single print quality characteristic is detected for each flat printed product  40 . 
         [0055]    The information representing the detected characteristic is transferred using the first data line  62  to the management device  60 , which compares the information representing the detected characteristic to the corresponding standard and, based on that comparison, assigns the detected characteristic unequivocally to one of the at least two predefined quality statuses. In this way, the management device  60  generates the first information  77  representing the quality status determined by the management device  60 . The first information  77  representing the determined quality status is then stored in the storage device  50 . The second information  78  associating the first information  77  with the flat printed product  40  for which the first information  77  was created is also generated by the management device  60  and stored together with the first information  77  in the storage device  50 . 
         [0056]    Then, the flat printed products  40  are stacked on one or more piles  87 , independently of the first information  77 . The total number of flat printed products  40  of each pile  87  is measured continuously or at predetermined intervals, either by the device  95  for height- and/or weight-based measurement of the stacked flat printed products  40 , or by synchronizing the counter  42  of the printing press  10  with the management device  60   
         [0057]    Using the management device  60 , the first information  77  and second information  78  for all of the flat printed products  40  stacked on the same pile  87  are grouped together for each pile  87  forming the group of information  85  for each pile  87 . Each group of information  85  is stored in the storage device  50 . 
         [0058]    In the case of several piles  87 , it is necessary to be able to identify, for each pile  87 , the group of information  85  with which the pile  87  is associated and which is stored together with the groups of information  85  of the other piles  87  in the storage device  50  using an identification method. 
         [0059]    According to a first embodiment of this identification method, the management device  60  generates, for each pair [pile  87 —group of information  85 ], a reference information  120  that is stored on the one hand with the pile  87  and on the other hand with the group of information  85  stored for the corresponding pile  87  in the storage means  50 . Each pile  87  and each group of information  85  can therefore be identified by the reference information  120  attributed to them. The reference information  120  is for example a bar code. 
         [0060]    According to a second embodiment of the identification method, the group of information  85  is stored on the computer medium  100  arranged on the support  90  supporting the pile  87  associated with the group of information  85 . In this case, each pile  87  is associated with a computer medium  100 . Thus, the group of information  85  stored locally with the pile  87  with which the group of information  85  is associated. 
         [0061]    Also alternatively, the first embodiment of the identification method based on the reference information  120  and the second embodiment of the method based on the computer medium  100  can be combined, for example for security reasons. 
         [0062]    In the event the measuring device  95  detects that part of the flat printed products  40  is withdrawn from the pile  87 , an information representing the number of withdrawn flat printed products  40  is sent to the management device  60  using the third data line  97 . The first information  77  and second information  78  associated with the withdrawn flat printed products  40  are thus removed from the group of information  85  associated with the pile  87  from which the flat printed products  40  are removed. As a result, the withdrawal of flat printed products  40  does not create an inconsistency between the group of information  85  and the related pile  87 . 
         [0063]    The processing method according to the invention is adapted to know, at all times during production, the total number of flat printed products  40  and the number of flat printed products  40  belonging to one or each quality status. Moreover, it is possible to know, at any time during production, for each pile  87 , the number of flat printed products  40  belonging to one or each quality status. This information can be summarized in a report  115  accessible for a user. 
         [0064]    For example, two quality statuses exist, in particular “good” and “bad,” meaning that the quality of the flat printed product  40  meets or does not meet, respectively, predefined quality criteria. The production of flat printed products  40  can be stopped when the total number of products  40  having “good” status is reached. Relative to the processing methods of the prior art, it is not necessary to over estimate or overdimension production to ensure that the number of products  40  having the “good” status is actually reached. This represents savings in terms of production time and production cost. 
         [0065]    Based on the identification methods described above, it is possible to know, for each flat printed product  40  in each pile  87 , the quality status. This information is useful for example to sort the stacked flat printed products  40 , the sorting depending on the first information  77 , in particular according to their quality status. The sorting step can comprise a step for separating the flat printed products  40  with “good” status from flat printed products  40  with “bad” status. The flat printed products  40  with “good” status are then used for the continuation of the production. 
         [0066]    Since the processing method according to the invention is adapted to accurately identify the products  40  with “bad” status, it is possible to eliminate only the products  40  with “bad” status from production and to keep all products  40  with “good” status. This again represents savings in terms of production cost and decreases the discard rate. 
         [0067]    Furthermore, the processing method and the processing device  5  according to the invention guarantee an objective quality assessment, i.e. completely identical, for each flat printed product  40  all throughout production.