Patent Publication Number: US-6705981-B2

Title: Device for retention of products on a transporting surface in a folder

Description:
FIELD OF THE INVENTION 
     The present invention is related to a device for a retention of products on a transporting surface in a folder, particularly for web-fed rotary printing presses. 
     BACKGROUND OF THE INVENTION 
     U.S. Pat. No. 2,031,780 is related to a rotary cutting and folding mechanism for printing machines. In this solution pins are disclosed, carried by one of the folding cylinders to temporarily hold the leading edge of the web or the sheets. According to this disclosure retractable pin elements are assigned to a cutting knife arranged on a cutting cylinder and corresponding anvil bars are assigned to a folding cylinder. Said pin elements are arranged as to penetrate an incoming web of material or a sheet to be seized on a respective transporting cylinder&#39;s surface. A product rim being penetrated by punched holes of said pin elements is subject to further trimming operations when finishing the respective folded products and nowadays primarily is acceptable by the customer only on newspapers. 
     U.S. Pat. No. 1,900,288 discloses a folding cylinder to the surface of which a plurality of anvil bars is assigned. Similar to the disclosure according to U.S. Pat. No. 2,031,780 previously described, retractable pin elements are assigned to each of said anvil bars. Said anvil bars cooperate with knives received on the circumference of a cutting cylinder. Said pin elements are mounted within the interior of said folding cylinder. Similar to the disclosure according to U.S. Pat. No. 2,031,780 said retractably mounted pin elements penetrate said products to be conveyed on the surface of the respective folding cylinder. 
     U.S. Pat. No. 4,445,881 is related to a method and apparatus for improving newspaper folding and cutting mechanisms. The improvement is related to folding newspapers in the collecting mode. Inside and outside web sections are printed with the same number of lines and transferred to a folding cylinder which collects them in an overlapping relation. Expanding means incorporated in the body of the cylinder expand its effective radius to permit the trailing edge of the outside section to be cut to a length equal to that of the inside section without recutting the inside section again. The collected sections are then passed through second fold rollers for final folding. 
     U.S. Pat. No. 5,122,109 concerns a folding drum in a folding apparatus for a rotary printing press. Tips of folding blades project to the outside of the folding drum through gaps between the respective blades. At least two bands are integrally connected by a respective band mount position with a plurality of groups of such integrally connected bands being provided. Each band mount position is mounted to the folding drum via respective adjusting devices such that the expansion of the bands of each group of the folding drum can be adjusted. Preferably each adjusting device includes an adjusting plate engaged with an adjusting rack to which the bands are mounted and an adjusting shaft. The adjusting plate is mounted to the adjusting shaft at an eccentric position with respect to its engagement with the adjusting rack. 
     In known folders according to the state of the art, a set of cutting cylinders is included to create the signatures which are then forwarded into an accelerator section made of strips of transferring material such as tapes, to give an example. 
     Several methods are employed to prevent the signatures from opening after it has been severed from a web of material and forwarded into respective sets of tapes. At high speeds the forces acting on the book are too large and render most of these methods ineffective. 
     Other methods include cutting a portion of signature in the cutting cylinders&#39; area, then performing the final cut in a second pair of cutting cylinders or directly on a pinless transfer cylinder. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to prevent respective leading edges of web of materials from opening up during a transitory period after the previous signature has been severed from the web of material. 
     A still further object of the present invention is to introduce a respective leading edge of a web of material into a set of tapes accurately, the respective sets of tapes assigned to a further cylinder of a respective folder apparatus. 
     According to the invention, a device for seizing flat material comprises: 
     a transfer cylinder rotating about an axis and having an outer surface, 
     a cutting cylinder cooperating with said transfer cylinder, said cutting cylinder having at least one knife mounted thereon, and 
     a set of product seizing elements arranged on the outer periphery of said cutting cylinder actuatable about a common center point, tips of said product seizing elements cooperating with counterparts on the surface of said transfer cylinder. 
     The advantages of the present invention are to be seen in that the leading edge of webs of material is under positive control upon a respective transitory period after the respective previous signature has been cut from said web of material. Thus, an opening up of the respective leading edge is prevented. An opening of the respective leading edge of the web of material would result in an inaccurate insertion or the occurrence of dog ears of the respective leading edge upon transfer of said leading edge into a respective sets of tapes after the transitory period. The accuracy of product transfer during the respective transitory period determines the accuracy of folding operations during the respective signature&#39;s transport through the folder apparatus. 
     In further embodiments of the present invention said product seizing elements are arranged on the surface of a cutting cylinder and actuated when a respective new leading edge travels upon the respective circumference of a transfer cylinder. To allow for seizing the entire leading edge of the respective web of material, said product seizing elements may be arranged spaced apart from each other, extending over the entire width of the respective cutting cylinder. To allow for a relative movement of said product seizing elements said product seizing elements being shaped as finger elements are rotatably mounted in brackets. Said brackets are to be arranged in a simple and easy manner on the respective face portions of the cutting cylinder for example. To allow for simultaneous movement of the respective product seizing elements when actuated said seizing elements are arranged on a common axis. 
     Said common axis is journalled in respective levers which are rotatably mounted about center points to allow for a seizing movement of said product seizing elements. Said seizing movement occurs when a respective dwell sections of a cam element assigned to said cutting cylinder actuates a cam follower mounted to said lever which is mounted pivotably about the previously mentioned center point. 
     The seizing movement of the tips of the respective seizing elements is initialized when a previously cut signature from the leading edge of the web of material is created. Then, said tips of said product seizing elements engage said newly created leading edge positioned above a respective counterpart for a cutting operation. To allow for a supported but still flexible seizing operation, said leading edge of a web of material is positioned above an anvil bar received in respective grooves on the surface of said transfer cylinder, the anvil bars having a rather elongated shape to enlarge said leading edges seizing zone. 
     Said product seizing elements are preferably mounted to respective product conducting cylinders or pinless folders assigned to respective web-fed rotary printing presses for commercial and newspaper printing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both to its construction and its method of operation together with additional objects and advantages thereof, will be best understood from the following description of a specific embodiment, when read in connection with the accompanying drawings, in which: 
     FIG. 1 is a schematically given view of a web travel path into the cutting nip between two cooperating cylinders of a folder assembly, 
     FIG. 2 a  shows product seizing elements seizing a respective leading edge of a web of material prior of insertion into a belt entry, 
     FIG. 2 b  shows a respective leading edge of a web of material prior to its release by said product seizing elements 
     FIG. 3 shows a perspective view of a respective arrangement of product seizing elements extending over the width of a paper conducting cylinder such as a cutting cylinder and 
     FIG. 4 shows a perspective view of a respective arrangement of product seizing elements which fit within a paper conducting cylinder such as a cutting cylinder. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In FIG. 1 a schematically side elevation of a web travel path into the cutting nip between two cooperating cylinders in a folder assembly is given. 
     In this configuration of a folder assembly  35 , a former board  2  is arranged prior to respective pair of nip rollers  4 , which receive a longitudinally folded web of material  1 . The respective web of material  1  could as well be received from said pair of nip rollers  4  without being longitudinally folded by said former board  2  previously arranged. After passing of a second pair of nip rollers  40  said web of material  1  is received within a nip between a cutting cylinder  3  having an outer surface  15  and a transfer cylinder  6  having an outer surface  16 , respectively. Said cutting cylinder  3  rotates about an axis  23 , whereas said transfer cylinder  6  is rotating about an axis  24 , respectively. Below a transfer area within which said web of material  1  is transferred to a respective transfer cylinder&#39;s  6  surface  16  a set of tapes  8  is arranged, into which the respective products severed from the respective leading edge will be inserted. In a fixed position with a center point concentric to the first cylinder  3  a cam element  10  is mounted which serves for an actuating purpose of product seizing elements  7  given in greater detail in FIGS. 2 a ,  2   b , respectively. To said surface  15  of the cutting cylinder  3  at least one knife  5  is assigned, cooperating with respective counterparts  9  assigned to the surface  16  of said transfer cylinder  6 . Said at least one knife  5  on the circumference of the cutting cylinder  3  is received in a knife box  17  for easier exchange and fixing thereof. Said sets of tapes  8  capturing the respective leading edge of the web of material  1  after the transitory period rotate about pulleys  14 , one of which is only schematically given here. 
     FIG. 2 a  shows product seizing elements seizing a respective leading edge of a web of material supported by a respective counterpart prior to the set of tapes. 
     FIG. 2 a  shows said transfer cylinder  6  to be rotated in a sense of rotation  27  given by the arrow in the vicinity of the transfer cylinder&#39;s surface  16 . The respective leading edge section  13  of a web of material  1  supported by said surface  16  of the transfer cylinder  6 . The cutting edge of said leading edge  13  is located above a cutting counterpart  9 , for example an anvil bar, having a substantially rectangular shape. Said anvil bar is received in a groove of said transfer cylinder  6 . The rectangular shape of said counterpart  9  provides for a larger product seizing zone on the respective surface  16  of the transfer cylinder due to the enhanced length circumferential direction of said counterpart  9 . 
     The respective cooperating cylinder  3 , for instance a cutting cylinder comprises an outer surface  15 . Into said outer surface  15  of said cutting cylinder  3  a plurality of knife boxes  17  are received, each knife box having a respective knife  5 . Both cylinders, i.e. cutting cylinder  3  and transfer cylinder  6  are faced such that counterparts  9  and said knives  5  assigned to the respective cylinder when cooperating which each other sever a respective signature from the respective leading edge  13  of the web of material  1 . To the outer periphery of said cutting cylinder  3  an actuating element  10  is assigned of which only a portion is shown here. The outer periphery of said cutting cylinder  3  further comprises bracket elements  21  of which only one is given in the embodiment according to FIG. 2 a . In said bracket elements  21  levers  20  are rotatably mounted about a center point  11  given in dashed lines in the embodiment according to FIG.  1 . Said lever elements  20  comprise a set of product seizing elements  7 , which are located in a gap  15   a  in cylinder surface  15 , gap  15   a  being shown schematically by dashed lines and in more detail in FIG.  3 . Said product seizing elements  7  assigned to said lever  20  are longitudinally extended finger-shaped elements having a tip  25  and provided for cooperation upon actuation with said leading edge  13  of the web of material  1  supported by said counterparts  9  on the surface  16  of said transfer cylinder  6 . Said product seizing elements  7  being received within a lever  20  are arranged on a common axis  18  extending over the entire width of said paper conducting cylinder such as a cutting cylinder  3 . To secure the seizing movement with respect to the leading edge  13  of the web of material  1  said set of seizing elements is keyed by a key  19  within said lever  20 . The movement of said lever  20  about said center point  11  is actuated by an actuating element  12  such as a cam follower, cooperating with the respective surface of said cam element  10  assigned to one face of said cutting cylinder  3 . Said lever  20  rotatably received about said center point  11  may be spring biased for actuation and is actuated by respective high and low dwell portions of said cam element  10 , when cooperating with said cam follower  12 . Said cutting cylinder  3  substantially rotates in a sense of rotation indicated by reference numeral  26  assigned to the respective arrow. 
     FIG. 2 b  shows a respective leading edge  13  of a web of material  1  prior to release by said product seizing elements  7  assigned to said cutting cylinder  3 . 
     In this stage of rotation of said paper conducting cylinders  3 ,  6 , respectively, said leading edge  13  received on the surface  16  of said transfer cylinder  6  has moved upon rotation of said cylinders into the respective senses of rotation  26 ,  27 , respectively, towards the entry section of said sets of tapes  8  rotating about pulleys  14 . As can be derived from the configuration according to FIG. 2 b  said levers  20  receiving said cam follower  12  have been actuated via the surface of the cam element  10  assigned to said cutting cylinder  3  rotating the respective sets of tapes to seize the respective leading edge  13  received above the counterpart  9 . Thus, during the transitory period after a previously severed signature has been inserted into the sense of tapes  8  positive control is exerted upon the respective leading edge and prevents the respective leading edge  13  of the web of material  1  from opening up. The facing of the actuating movement of said levers  20  receiving said product seizing elements  7  about the center point  11  is faced such that upon common rotation of said cylinders  3 ,  6 , respectively, said product seizing elements&#39;  7  tips  25  are maintained in continuous contact with the respective leading edge  13  of the web of material  1 . Thus, upon common rotation of the product seizing elements  7  engaging the respective leading edge  13  of the web of material  1  the lever  20  actuated via cam follower  12  cooperating with cam elements  10  adopts an inclined position  29  shown in FIG. 2 b.    
     The respective cam followers  12  which are used for an actuating element of said levers  20  about said center point  11  are mounted on respective cam follower axis  34  in cooperation with said cam element  10 , the cam follower  12  actuates said lever  20  about its respective center point  11  to control the position of product seizing elements  7  relative to the transfer cylinder&#39;s  6  surface  16 . The actuation of the product seizing elements&#39; tips is such that the finger-shaped product seizing elements  7  continue to hold the leading edge  13  of the web of material  1  onto the surface  16  of the respective transfer cylinder  6 . The facing is maintained until said respective product leading edge  13  is captured by the sets of tapes  8  rotating about pulleys  14 . After the sets of tapes  8  have received the respective leading edge which is later on severed from the web of material  1  by a cutting operation of a further knife  5  and a further counterpart  9  on the respective cylinders  3  and  6 , respectively, the fingers are free to move away from the respective transfer cylinder&#39;s surface  16  and rotate around the cutting cylinder  3  for a next seizing movement of a newly created respective leading edge. 
     To the respective surface  15  of a cutting cylinder a plurality of product seizing elements  7  can be assigned, preferably in the vicinity of respective knife assemblies  5  which are received in knife boxes  17 , for instance. The number of knife assemblies  5  on the surface of the respective cutting cylinder  3  determines the number of cutting counterparts  9  being received in respective grooves on the surface of said transfer cylinder  6 . 
     FIG. 3 shows a perspective view of a respective arrangement of product seizing elements extending over the width of a cutting cylinder. 
     Said cutting cylinder  3  given in a partial view here comprises two face elements to which brackets  21  are assigned. Said brackets receive said actuatable levers  20  in center points  11  said levers being actuated by actuating elements  12  such as given as cam followers. Said cam followers  12  are received in respective axis  34  on said lever elements  20  having a substantially L-shaped configuration. Said levers  20  assigned to the brackets arranged on both faces of the cutting cylinder  3  further comprise a common axis of rotation  18 . On said axis of rotation  18 , which is beneath surface  15 , said finger-shaped product seizing elements  7  are arranged in a surface gap  15   a  spaced from one another by a spacing  31  over the entire width  33  of the cutting cylinder  3 . The spacing  31  of the respective product seizing elements  7  over the entire width of said surface  15  of the cutting cylinder  3  provides for a simultaneously occurring seizing of the respective leading edge  13  of the web of material  1  to be processed. Further, the spacing  31  serves the purpose to provide a location for passage through the tape trollies or pulleys. In the configuration according to FIG. 3 said knife tips  32  of said knife elements  5  received in boxes  17  in the respective surface  15  of the cutting cylinder  3  are shown in greater detail. Said tips  25  of the respective product seizing elements  7  may comprise pads for having elastic properties to facilitate a smooth seizing action on the respective leading edge  13  of the web of material  1 . 
     The cam motion can withdrawal the product seizing elements  7  into gap  15   a  as the elements  7  pass through the nip, and then extend the elements  15  beyond surface  15   a  as shown in FIGS. 2 a  and  2   b . Besides a cam activated actuation of the respective product seizing elements  7  on cutting cylinder  3  a remote controlled activation of said seizing motion may be conceivable as well. To this end to the respective end portions of the common axis  18  to which the respective product seizing elements  7  are commonly mounted electrical actuators such as electric motors may be assigned, which are remote controlled and could be activated on a respective seizing action of a leading edge  13 . 
     FIG. 4 shows the elements  7  and the support and actuating device for the fingers, removed from cylinder  3 . The respective identification numbers are similar to those in FIG.  3 . 
     Product seizing elements according to the present invention are preferably used in pinless folder assemblies  35  assigned to rotary printing presses for commercial and newspaper purposes. 
     
       
         
           
               
             
               
                   
               
               
                 Reference Numeral List 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                  1 
                 web of material 
               
               
                   
                  2 
                 former board 
               
               
                   
                  3 
                 cutting cylinder 
               
               
                   
                  4 
                 pair of nips 
               
               
                   
                  5 
                 knives 
               
               
                   
                  6 
                 transfer cylinder 
               
               
                   
                  7 
                 product seizing elements 
               
               
                   
                  8 
                 set of tapes 
               
               
                   
                  9 
                 cutting counterpart 
               
               
                   
                 10 
                 cam 
               
               
                   
                 11 
                 center point 
               
               
                   
                 12 
                 cam follower 
               
               
                   
                 13 
                 leading edge 
               
               
                   
                 14 
                 pulleys 
               
               
                   
                 15 
                 cutting cylinder surface 
               
               
                   
                 15a 
                 gap 
               
               
                   
                 16 
                 transfer cylinder surface 
               
               
                   
                 17 
                 knife box 
               
               
                   
                 18 
                 axis 
               
               
                   
                 19 
                 key 
               
               
                   
                 20 
                 lever 
               
               
                   
                 21 
                 bracket 
               
               
                   
                 22 
                 cam dwell section 
               
               
                   
                 23 
                 rotating axis cutting cylinder 
               
               
                   
                 24 
                 rotating axis transfer cylinder 
               
               
                   
                 25 
                 seizing element tip 
               
               
                   
                 26 
                 sense of rotation 
               
               
                   
                 27 
                 sense of rotation 
               
               
                   
                 28 
                 cut 
               
               
                   
                 29 
                 inclined lever position 
               
               
                   
                 30 
                 lever mounting axis 
               
               
                   
                 31 
                 spacing 
               
               
                   
                 32 
                 knife tip 
               
               
                   
                 33 
                 cylinder width 
               
               
                   
                 34 
                 cam follower axis 
               
               
                   
                 35 
                 folder assembly 
               
               
                   
                 40 
                 nip rollers