Patent Publication Number: US-7216587-B2

Title: Method of dispensing metal-backed printing blankets

Description:
CROSS REFERENCE OF RELATED APPLICATIONS 
   This application is a continuation-in-part of U.S. patent application Ser. No. 10/198,598, filed Jul. 18, 2002 now U.S. Pat. No. 6,827,017, which is a divisional and claims the benefit of U.S. patent application Ser. No. 09/860,087 filed May 17, 2001, now U.S. Pat. No. 6,540,076 issued Apr. 1, 2003. 

   BACKGROUND OF THE INVENTION 
   This invention relates to a carton blank and carton for packaging and dispensing a printing blanket, and more particularly to a method of using a carton which permits the alignment and controlled feeding of a metal-backed printing blanket onto a rotating print cylinder of a printing press. 
   The most common commercial printing process is offset lithography. In this printing process, ink is offset from a printing plate to a rubber blanket mounted on a cylinder before being transferred to a substrate, such as paper. Typically, the cylinder comprises a metal cylinder having an encircling rubber printing blanket which is releasably mounted to the cylinder. The rubber printing blanket may be reinforced with either a cloth back or a metal back. Unlike the cloth back, the metal back adds durability to the carried rubber layer(s) on the blanket by removing stress which occurs from tensioning the printing blanket as it is mounted on the metal cylinder. 
   However, with a cloth back the printing blanket may be rolled upon removal from its shipping carton and maintained as a roll by finger pressure. This minimal amount of handling pressure permits two operators to easily align the blanket in a locking device which is typically located in a longitudinal gap in the metal cylinder. Additionally, as the cylinder rotates to mount the blanket thereon, the operators can easily control the tension and alignment of the unrolling blanket with such minimal handling pressure. 
   With a metal-backed printing blanket, the metal sheet strongly desires to uncoil upon removal from a conventional shipping carton. The handling pressure needed to maintain the metal-backed blanket as a coil makes it difficult for the operators to properly insert and align the blanket into the locking device of the cylinder. Additionally, the resistance of the blanket to being coiled makes it difficult to control the tension and alignment of the blanket as it unrolls onto the rotating cylinder. Such problems have resulted in a high percentage of ruined metal-backed blankets due to improper installation. 
   Accordingly, there is a need in the printing industry for an improved procedure or device which maintains the coiled condition of the blanket and permits the dispensing of a metal-backed printing blanket to a print cylinder in a controlled fashion. 
   SUMMARY OF THE INVENTION 
   The above-mentioned needs are met by the present invention in which a shipping carton for a metal-backed printing blanket is provided. The shipping carton is adapted to permit the proper loading of the blanket onto a printing press cylinder. As it will appear in the more detailed description and drawings, the carton provides for the formation of a lengthwise slit from which to dispense the enclosed blanket in a controlled fashion. The shape of the carton may vary, and encompasses any common geometrical shape including rectangular, triangular, cylindrical, and the like. 
   In a first embodiment, the carton is substantially rectangular in shape, is formed preferably from a one piece blank of retail packaging type cardboard, and has from one end of the blank to the other first, second, third, fourth, and fifth panels. The first and fifth panels are folded from the second and fourth panels, respectively, so that the first panel lies substantially parallel to and outside the fifth panel with its edge secured adjacently to the fourth panel. Pull tabs are provided in the third panel in order to permit the formation of a lengthwise slit adjacent the edge of the third panel by an operator. The slit once formed, permits the mounting end of the metal-backed printing blanket to be removed from the carton. Reference lines are also optionally provided on the third panel. These reference lines may be used to draw alignment marks on a dispensed portion of the printing blanket for proper insertion into a locking device of the blanket cylinder. 
   All but the third panel have pairs of flaps together forming the two sides of the carton. In particular, the fourth panel includes a pair of doubled-winged flaps having handholds. Each double-winged flap comprises a body foldably attached between inner and outer flaps. The body forms a space between the inner and outer flaps when the outer flap is folded over the inner flap. All the flaps of the carton together help to form strong handholds in the sides of the carton. The handholds permit two operators to have control of the blanket for tension and proper alignment as the blanket is fed out of the carton and mounted on a rotating cylinder. 
   In second and third embodiments of the present invention, the carton is provided in the form of a cylindrical tube and a triangular tube, respectively. In these embodiments, the mounting end of the rolled blanket is still dispensed through a side wall of the carton. Handles and/or indentations are also provided such that the carton may be easily gripped to facilitate control over the alignment and tension of a dispensing blanket from the carton onto a rotating blanket cylinder. Alignment marks may additionally be provided to each of these embodiments. 
   In accordance with one aspect of the present invention, provided is a carton blank for a carton to contain a metal-backed printing blanket in a roll and from which to dispense the blanket. The blank comprises at least first, second, and third panels in the order named from one end of the blank to the other and foldable with respect to each other, one of the panels being capable of dispensing the blanket in a controlled fashion, and at least one of the panels having a pair of side flaps to form sides of the carton. 
   In accordance with another aspect of the present invention, provided is a carton to contain a metal-backed printing blanket in a roll, the carton comprising at least one panel through which to dispense the printing blanket. 
   In accordance with yet another aspect of the present invention, provided is a carton to contain a metal-backed printing blanket in a roll and from which to dispense the printing blanket. The carton comprises first, second, third, fourth, fifth, and side panels in which a lower edge of the first panel is secured to the fifth panel. Pull tabs for forming a lengthwise slit in the carton are provided generally in the plane of the third panel. 
   In accordance with still another aspect of the present invention, provided is a method of mounting a rolled printing blanket to a blanket cylinder in a printing press. The method comprises the steps of providing a carton containing the rolled printing blanket, opening a slit lengthwise in the carton to withdraw a mounting end of the printing blanket, and securing the mounting end in a locking device of the cylinder. The method further includes rotating the cylinder, and controlling the alignment and tension of the printing blanket as it mounts on the rotating cylinder until the printing blanket is completely dispensed from the carton. 
   These, and other features and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a view of an exterior side of a carton blank laid out flat. 
       FIG. 2  is a view of an interior side of the carton blank of  FIG. 1  laid out flat. 
       FIG. 3  is a perspective view of an assembled carton, partially cut away, containing a rolled metal-backed printing blanket ready to be dispensed from the carton, and with a pull tab partially removed. 
       FIG. 4  is a perspective view of the carton with pull tabs removed from a third panel and a portion of the metal-backed printing blanket dispensed from the carton such that the blanket may be marked with reference to alignment lines provide on the third panel. 
       FIG. 5  is a top plan view of the opened carton with a mounting end of the printing blanket being aligned and secured to a print cylinder. 
       FIG. 6  is a side view of the carton showing the printing blanket as it is dispensed from the carton in a controlled fashion. 
       FIG. 7  is a perspective view of an alternative embodiment of a carton according to the present invention. 
       FIG. 8  is a perspective view of another alternative embodiment of a carton according to the present invention. 
       FIG. 9  is a side view of one embodiment of a metal back printing blanket suitable for dispensing from a carton according to the present invention. 
       FIG. 10  is a side view of one embodiment of a metal back printing blanket suitable for dispensing from a carton according to the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   A carton blank is denoted by the numeral  2  in  FIGS. 1 and 2  for making a carton, indicated by the numeral  4  in  FIGS. 3–6 . The carton  4  is specifically developed and is particularly well adapted for packaging, shipping, and dispensing in a controlled fashion, a rolled printing blanket which functions as a replaceable layer to a blanket cylinder on a printing press. A rolled printing blanket is designated by the letter “R” in  FIGS. 3–8 . The construction of the printing blanket, other than having a metal backing or base layer, is not important to an understanding of the invention. Printing blanket constructions are known in the art. 
     FIG. 1  shows the exterior side of the blank  2 , and  FIG. 2  shows the interior side thereof. Although the carton blank  2  is preferably a single piece, it should be apparent to those persons skilled in the art that the carton blank could be formed by assembling (glued, stapled, etc.) several pieces together. Additionally, although the preferred carton blank  2  comprises five panels with four pairs of flaps, as will be explained hereafter, it is to be appreciated that other blank designs, such for example as one that has four panels or another with at least one pair of flaps to form the sides, may be used as the dispensing carton for a metal-backed printing blanket without departing from the scope and spirit of the present invention. Furthermore, although cardboard is preferred, it should be apparent to those persons skilled in the art that other corrugated and noncorrugated materials such as, and not limited to, paperboard, plastics, and metal could be used to form a carton according to the present invention. 
   Referring particularly to  FIG. 1 , the blank  2  has a first panel  8 , a second panel  10 , a third panel  12 , a fourth panel  14 , and a fifth panel  16 , and for convenience, are named in order from one end of the blank to the other. The panels are foldable with respect to each other along lines of weakness W. 
   The third panel  12  includes a pair of opposed score lines  18 , i.e., perforations, and a generally vertical cut  20  extending there between which together form a pair of pull tabs  22   a  and  22   b . As such, the pull tabs  22   a  and  22   b  are disposed generally within the plane of the third panel  12 . As shown in  FIG. 2  the pull tabs  22   a  and  22   b  on the interior side of the blank  2  are secured to a respective end of an adhesive strip  24   a  and  24   b . The adhesive strips  24   a  and  24   b  are secured to the interior side and run substantially the full length of the third panel adjacent the line of weakness W that is between the third panel  12  and the fourth panel  14 . The use of the adhesive strip will be explained further in a later discussion in reference to  FIG. 3 . 
   As shown in  FIG. 1 , each of the first, third, fourth and fifth panels  8 ,  12 ,  14  and  16  have a pair of side flaps  8   f ,  12   f ,  14   f  and  16   f  which is foldably attached to its side edges  8   e ,  12   e ,  14   e  and  16   e . Each side flap  14   f  of the fourth panel  14  is a double-winged flap having an outer flap  14   f   o , an inner flap  14   f   i , and a body  14   f   b . The body is foldably attached to both the outer and inner flaps along its edges, and creates a space between the outer and inner flaps when folded over each other. Each outer flap  14   f   o  includes a hand hole  26 , which is sized to permit an associated hand flap  28  provided on the inner flap  14   f   i  to fold into when the inner and outer flaps are folded over and the hand flap is pushed inwards by an operator&#39;s hand. A tab  30  provided at the end of each outer flap  14   f   o  engages in a tab hole  32  which secures the outer flap  14   f   o  folded over the interior side of the inner flap  14   f   i . Accordingly, the pairs of side flaps  8   f ,  12   f ,  14   f , and  16   f  overlap each other to form sides  34  ( FIG. 3 ) of the carton  4 . It is to be appreciated that the overlapping of the side flaps  8   f ,  12   f ,  14   f , and  16   f , and the sizing of the hand hole  26  and hand flap  28  form a pair of durable handholds  36  ( FIG. 3 ) which an operator may securely grasp for control of the carton  4 . The pairs of flaps  12   f  and  16   f  of the third and fifth panels  12 ,  16 , respectively, have cutouts  33  so not to block the handholds  36 . Additionally, the side flaps  8   f  of the first panel  8  are shaped such that they also do not block the handhold  36  when positioned in the sides  34  of the formed carton  4  as will be explained hereafter. 
   To form the carton  4  into an erected boxlike condition that is illustrated in  FIG. 3 , flaps  12   f  and  16   f  are folded toward the interior side of the blank  2  and on each side, and the flaps of the third and fifth panels  12 ,  16  are brought together end-to-end. At this point in the assembly of the carton, the third panel  12  and the fifth panel  16  are standing perpendicular to the fourth panel  14 . Next, on each side of the carton  4 , the outer flap  14   f   o  of the fourth panel  14  is folded over both its inner flap  14   f   i  and the touching flaps  12   f  and  16   f , and secured inward of these flaps by inserting its tab  30  into the associated tab hole  32 . This arrangement forms an open box, and after placing a rolled printing blanket R therein, the first panel  8  is folded in parallel over the fifth panel  16  closing the opening with the second panel  10 . The flaps  8   f  of the first panel  8  are then inserted between the inner flaps  14   f   i  of the fourth panel  14  and the flaps  16   f  of the fifth panel  16  to complete the sides  34 . A lower edge  35  of the first panel  8  is secured adjacently an edge of the fifth panel  16  in any conventional fashion such as gluing or taping to complete the erected carton  4  as seen in  FIG. 3 . 
   When an operator wants to dispense the rolled metal-backed printing blanket R for the purpose of mounting it to a blanket cylinder, the operator first opens the carton  4  by pulling on the provided pull tabs  22   a  and  22   b , which is illustrated in  FIG. 3  showing pull tab  22   a  being partially removed. Removing the pull tabs  22   a  and  22   b  pulls the adhesive strips  24   a  and  24   b  ( FIG. 2 ) through the interior side of the third panel  12 , tearing a lengthwise slit  38  in the carton  4 . 
   As illustrated in  FIG. 4 , showing a perspective view of the carton with the pull tabs  22   a  and  22   b  removed from the third panel  12 , through the lengthwise slit  38  a mounting end  40  of the rolled printing blanket R is then drawn from the carton  4 . A pair of parallel lines  42  are optionally provided on the exterior side of the third panel  12  and may be used as a quick reference to make alignment marks  43  adjacent the mounting end  40  on a rear surface  44  of the printing blanket R. With such an alignment marks  43 , the printing blanket R may be placed properly within a locking device  46  of a blanket cylinder  48 , which is shown in  FIGS. 5 and 6 . Preferably, the parallel lines are spaced apart an amount by which the mounting end  40  of the printing blanket R is inserted into the locking device  46 . Typically, this amount is about 3″ inches (7 to 8 cm). 
   After making alignment marks, the mounting end  40  of the printing blanket is aligned and secured to the locking device  46  in the blanket cylinder  48  which is illustrated in  FIG. 5  showing a top plan view thereof. Once the mounting end  40  of the printing blanket R is properly locked in place, the cylinder  48  is then rotated which dispenses the remaining portion of the rolled printing blanket from the carton  4 . As the printing blanket R is dispensed from the carton  4 , it is mounted to the blanket cylinder  48  as illustrated in  FIG. 6 . It is to be appreciated that because the operators do not have to concern themselves with maintaining the printing blanket in a roll, as the print cylinder  48  rotates, the tension and alignment of the printing blanket R is easily controlled by the operators using the provided handholds  36  until the printing blanket is completely dispensed from the carton  4 . Additionally, dispensing the metal-backed printing blanket from the carton  4  minimizes the risk of damage to the blanket from misalignment. 
   It is to be appreciated that the above method of dispensing the rolled metal-backed printing blanket R is applicable to cartons of other shapes. For example, as illustrated in  FIG. 7 , the carton  4 , alternatively, may be formed in the shaped of a cylindrical tube  50  which is sized to contain the rolled blanket R. In this embodiment, the sides  34  may be formed of inserts or caps that seal up the ends of the cylinder tube  50 . In still another alternative embodiment, the carton  4  may be shaped in the form of a triangular-shaped box  52  which also sized to contain the rolled blanket R as illustrated in  FIG. 8 . Accordingly, the carton may be any box shape from which to dispense the rolled blanket R in a controlled fashion. 
   Additionally, other means for providing a lengthwise slit/opening in the carton  4  may be provided without departing from the scope and spirit of the present invention. For example, as illustrated in  FIG. 7 , an opening  54  may be provided. For shipping, the opening  54  could be sealed with a removable plug, or covered with plastic, metal foil, and/or tape. A dispensing tab  56  may be provided which has a first end portion exposed through the opening, and a second end portion attached to the mounting end  40  of the rolled blanket R. Accordingly, the dispensing tab  54  would be used to help guide and extract the mounting end  40  of the rolled blanket R through the opening  54 . Another example is illustrated by  FIG. 8 , wherein an opening in the carton  4  may be formed by a punch-out section  58  formed by perforations  60 . Furthermore, as illustrated in  FIG. 7 , handles  62  may be provided on the sides  34  of the carton  4 . Moreover, as shown in  FIG. 8 , an indentations  64  sized to be easily gripped by an operator&#39;s hand may be provided in each side  34  without departing from the scope and spirit of the present invention. What is important is that the sides  34  of the carton  4  be graspable in order to easily control the alignment and tension of a dispensing blanket onto a rotating cylinder. In both these alternative embodiments of  FIGS. 7 and 8 , reference lines  42  may optionally be provided. 
   It is to be appreciated that the above method of dispensing from a carton  4  is applicable to a number of types of rolled metal-backed printing blankets. For example, and not to be limited by, the metal-backed printing blanket R may be of the type such as a metal barred printing blanket as illustrated in  FIG. 9 , or a pre-bent metal backed printing blanket as illustrated in  FIG. 10 . The metal barred printing blanket  66  in  FIG. 9  has a pair of metal bar ends  68   a  and  68   b  attached to a fabric  70  having a compressive portion  72 . As illustrated by close-up section  9 A— 9 A in  FIG. 9 , each metal bar ends  68   a  and  68   b  is held by a respective locking device  46 , such that blanket  66  is clamped securely around the cylinder  48 . As illustrated by the close-up section  9 B— 9 B in  FIG. 9 , each metal bar end  68  is crimped to hold securely the fabric  70  therebetween. 
   The pre-bent metal backed printing blanket  74  illustrated by  FIG. 10  has a pair of ends  76   a  and  76   b  of a metal sheet  78  supporting a compressive portion  80  therebetween. The ends  74   a  and  74   b  are pre-bent by the manufacture and provided out of the carton  4  with the first end bent to alpha degrees, which is best shown by close-up section  10   a — 10   a , and the second end bent to beta degrees, which is best shown by close-up section  10   b — 10   b . Typically, beta is equal to 180°-alpha. As illustrated by close-up section  10   c — 10   c  in  FIG. 10 , the pre-bent ends  74   a  and  74   b  are held by the locking device  46 , such that blanket  74  is clamped securely around the cylinder  48 . 
   While certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those persons skilled in the art that various changes in the methods and apparatus disclosed herein may be made without departing from the scope of the invention.