Patent Publication Number: US-2011072993-A1

Title: Apparatus and method for cleaning guide rollers of a printing unit

Description:
This application claims the priority of German Patent Document No. 10 2007 010 761.9, filed Mar. 6, 2007, the disclosure of which is expressly incorporated by reference herein. 
     BACKGROUND AND SUMMARY OF THE INVENTION 
     The invention relates to an apparatus and method for cleaning guide rollers of a printing unit, in particular of a 9-cylinder satellite printing unit of a web-fed printing press. 
     Printing units of web-fed printing presses known from practice have several printing couples, wherein each printing couple features a transfer cylinder, a plate cylinder, an inking system as well as, if applicable, a dampening system. The plate cylinders are also designated as engraving cylinders and the transfer cylinders are also called blanket cylinders. In addition, these types of printing units feature impression cylinders, wherein an impression cylinder can cooperate with one or more transfer cylinders of different printing couples. The impression cylinders are also designated as satellite cylinders, which is why printing units with at least one impression cylinder are also called satellite printing units. In addition to satellite printing units that have impression cylinders, printing units that do not have any impression cylinders are known, wherein, in the case of printing units without impression cylinders, the transfer cylinders of two printing couples roll off one another. 
     A printing unit of a web-fed printing press that is embodied as a 9-cylinder satellite printing unit has four printing couples and consequently four plate cylinders as well as four transfer cylinders, wherein the transfer cylinders of all four printing couples roll off a common impression cylinder. A total of four print positions are embodied between the impression cylinder and the four transfer cylinders, whereby a to-be-printed printing substrate is conveyed through these print positions to be printed. 
     Thus, a to-be-printed printing substrate of a first print position of a 9-cylinder satellite printing unit is fed via a feed roller, and a printing substrate printed in such a satellite printing unit is discharged from the satellite printing unit starting from a fourth and thus final print position via a discharge roller. The printed printing substrate thus proceeds off the discharge roller with its print side that has just been printed in the printing unit, whereby there is a danger that printing ink will collect on the discharge roller that will impede transport of the printing substrate in the region of the discharge roller. Therefore, it is necessary to clean at least the discharge roller. Until now no cleaning devices for guide rollers of a printing unit have been known from practice, which permit effective cleaning of the guider rollers, in particular the discharge roller. 
     Starting herefrom, the present invention is based on the objective of creating a novel satellite cleaning device for guide rollers of a printing unit of a web-fed printing press. The cleaning device according to the invention has a cleaning body fastened to an actuating grip, which body can be inserted between guide rollers of a printing unit, wherein a cleaning cloth that can be wetted with cleaning fluid can be fastened to the cleaning body, and wherein the cleaning body features cleaning surfaces on opposing sides that are adapted to the contour of the guide rollers. Effective cleaning of the guide rollers, particularly the discharge roller, of a printing unit is possible with the inventive cleaning device. 
     The actuating grip preferably engages on an upper section of the cleaning body, whereby the cleaning surfaces are embodied on a lower section of the cleaning body, and whereby a clamping device is allocated to the upper section of the cleaning body, in order to clamp the cleaning cloth on the cleaning body. 
     Preferred developments of the invention are yielded from the following description. Without being limited hereto, one exemplary embodiment of the invention is explained in greater detail on the basis of the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-section of a 9-cylinder satellite printing unit together with an inventive cleaning device for the guide rollers of the printing unit. 
         FIG. 2  is a perspective view of a detail of the inventive cleaning device. 
         FIG. 3  is a side view of the cleaning device of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a cross-section of a printing unit  10  embodied as a 9-cylinder satellite printing unit in the region of two upper printing couples  11 ,  12 , wherein a plate cylinder  13 , a transfer cylinder  14  as well as rollers of an inking system  15  are depicted for each of the two upper printing couples  11 ,  12 . The two transfer cylinders  14  of the depicted printing couples  11 ,  12  roll off a common impression cylinder  16  each forming a nip  17  or  18 , whereby a printing substrate can be moved through the nip to be printed. 
     In order to convey a to-be-printed printing substrate in a defined manner through the print positions of the satellite printing unit  10 , the printing unit has two guide rollers, namely a so-called feed roller  19  and a so-called discharge roller  20 . A to-be-printed printing substrate is conveyed to the nip  17  via the feed roller  19  and, on the other hand, an already printed printing substrate is discharged from the printing unit  10  via the discharge roller  20  starting from the nip  18 . In the process, the side of the printing substrate printed in the printing unit  10  rolls off the discharge roller  20 , whereby the discharge roller can get contaminated by deposits of printing ink. 
     The present invention makes available a cleaning device  21  for cleaning the guider rollers of such a printing unit, particularly for cleaning the discharge roller  20  that is susceptible to contamination. The cleaning device  21  has a cleaning body  23  fastened to an actuating grip  22 , which can be inserted between guide rollers  19 ,  20  of the printing unit  10  as shown in  FIG. 1 . The cleaning body  23  has cleaning surfaces  24 ,  25  on opposing sides that are adapted to the contour of the guide rollers  19 ,  20 . In this case, the cleaning surfaces  24 ,  25  have an identical contour, just like the guide rollers  19 ,  20  of the printing unit  10  feature identical contours. 
     The actuating grip  22  engages on an upper section of the cleaning body  23  in an articulated manner, and the cleaning surfaces  24  and  25  are embodied on a lower section of the cleaning body  23 . An axis  26 , around which the cleaning body  23  is fastened in an articulated manner to the actuating grip  22 , extends perpendicularly to the longitudinal direction of the cleaning body  23  as well as to the longitudinal direction of the cleaning surfaces  24 ,  25  as shown in  FIG. 2 . 
     To clean the guide rollers  19 ,  20 , particularly the discharge roller  20 , a cleaning cloth (not shown) that can be wetted with cleaning fluid can be fastened to the cleaning body  23 , wherein a clamping device  27  allocated to the upper section of the cleaning body  23  is used for this. A cleaning cloth fastened to the cleaning body  23  with the aid of the clamping device  27  wraps around the cleaning body  23  in its longitudinal direction in such a way that the cleaning cloth covers the cleaning surfaces  24 ,  25  that are adapted to the contour of the guide rollers. 
     According to  FIG. 1 , to clean the guide rollers  19 ,  20  of the printing unit  10 , the cleaning device  21  with its cleaning body  23 , on which the cleaning cloth wetted with cleaning fluid is fastened, can be inserted from above between the guide rollers  19 ,  20 . 
     In a first cleaning step, a first cleaning surface  24  is adjacent to the feed roller  19  and a second cleaning surface  25  is adjacent to the discharge roller  20 , wherein by executing a swivel motion with the actuating grip  22 , the cleaning body  23  can be moved in this position over the entire axial extension of the guide rollers  19 ,  20 . This first cleaning step is used to loosen the contamination on the discharge roller  20 . 
     Then the cleaning body  23  of the cleaning device  21  is pulled out from between the guide rollers  19 ,  20 , rotated 180° and then re-inserted between the two guide rollers  19 ,  20  so that for a second cleaning step after rotating the cleaning device  21 , the first cleaning surface  24  of the cleaning body  23  is adjacent to the discharge roller  20  and the second cleaning surface  25  is adjacent to the feed roller  19 . During this second cleaning step, the already loosened contamination can be removed from discharge roller  20 . In this case as well, the cleaning body  23  is moved along the entire axial extension of the guide rollers  19 ,  20  via the actuating grip  22 . 
     The inventive cleaning device  21  is used accordingly to manually clean the guide rollers  19 ,  20 , whereby according to  FIG. 1 , an operator  28 , who actuates the cleaning device  21 , stands on a foot plate  29  above the guide rollers  19 ,  20 . In this standing position, the operator  28  can use the cleaning device  21  to effectively clean the guider rollers  19 ,  20  of the printing unit  10 , particularly the discharge roller  20  that is susceptible to contamination. 
     LIST OF REFERENCE NUMERALS 
     
         
           10  Printing unit 
           11  Printing couple 
           12  Printing couple 
           13  Plate cylinder 
           14  Transfer cylinder 
           15  Inking system 
           16  Impression cylinder 
           17  Nip 
           18  Nip 
           19  Feed roller 
           20  Discharge roller 
           21  Cleaning device 
           22  Actuating grip 
           23  Cleaning body 
           24  Cleaning surface 
           25  Cleaning surface 
           26  Axis 
           27  Clamping device 
           28  Operator 
           29  Foot plate 
       
    
     The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.