Abstract:
A plate punching assembly, comprising a base with a footprint, wherein the base has a slot configured to receive a printing plate. The footprint is comprised of a first actuator configured to actuate a first punch adapted to punch through the slot and into a first chaff disposal opening; the footprint also has a second actuator similarly configured. The first and second actuators are independently activated. In one embodiment, a chaff disposal collector is disposed over the footprint so that the chaff is collected in a secure fashion.

Description:
CROSS REFERENCE TO RELATED PATENT APPLICATIONS  
       [0001]     This application is a continuation-in-part of co-pending patent application U.S. Ser. No. 11/375,512, filed on Mar. 14, 2006. The entire disclosure of this United States patent document is hereby incorporated by reference into this specification. 
     
    
     FIELD OF THE INVENTION  
       [0002]     A plate punching assembly comprised of a base containing a slot and two chaff disposal openings, a first actuator adapted to actuate a first punch and to punch through the slot into a first chaff disposal opening, and a second actuator adapted to actuate a second punch and to punch through the slot into a second chaff disposal opening.  
       BACKGROUND OF THE INVENTION  
       [0003]     Current printing technology utilizes a variety of printing assemblies, including the “Computer-to-Plate” (CTP) system. This system is well known and is described, e.g., in U.S. Pat. No. 6,684,783 to Salvestro (method for imaging a media sleeve on a computer-to-plate imaging machine). Reference may also be had to U.S. Pat. Nos. 6,662,723; 6,526,886; 6,523,473; 6,523,472; and 6,457,413 to Loccufier (computer-to-plate by ink jet), and U.S. Pat. Nos. 5,992,324 and 5,738,014 to Rombult (met making lithographic printing plates in an automated computer to plate imaging system). The content of each of the aforementioned patents is hereby incorporated by reference into this specification.  
         [0004]     The plates used in a computer-to-plate system are often notched before being transferred to a printer. The notches on the plate are punched in a predetermined pattern that is designed to match the notches found within the printer. Such a mated-notch configuration ensures that the plate fits within the printer properly. Precise placement of these plates within the printer is required, especially when high resolution, color images are to be printed. Reference may be had to U.S. patent application 2005/0120899A1 to Gelbart (method for automated platemaking), U.S. Pat. No. 6,112,664 to Naniwa (plate making apparatus with a cutter and punch mechanism formed in one piece); and European Patent Application 0,985,528 to Okamura (improvements in and relating to the manufacture of printing plates). The content of each of the aforementioned patents and patent applications is hereby incorporated by reference into this specification.  
         [0005]     The printing art commonly utilizes certain notching patterns that are designed to match certain printers. Many notching patterns have been standardized, but there is still a wide variety of patterns found in the art.  
         [0006]     Commercial printing facilities often desire to purchase additional printing equipment. The managers of such facilities must use greater care to ensure all of the equipment they purchase utilizes the same, or a compatible, notching pattern. For example, should the facility be equipped with a new printer that utilizes Bacher style notches, but their existing equipment utilizes a Komori style notch system, the resulting incompatibility will necessitate the purchase of additional equipment.  
         [0007]     The prior art has attempted to solve this incompatibility problem by producing plate punching devices. A printing plate is disposed in such a device, and a suitable punching pattern is thereafter punched into the plate. In this manner, one can fabricate the desired notch pattern at the printing facility itself. However, the act of punching a notch in the plate results in the production of chaff particles. These chaff particles are of great concern to printers, as a single piece of loose chaff can easily disrupt the operation of the printing assembly, and thereby cause the printing process to stop.  
         [0008]     It is an object of this invention to provide an apparatus for punching a notch in a printing plate that is an improvement over prior art punching machines.  
       SUMMARY OF THE INVENTION  
       [0009]     In accordance with this invention, there is provided a plate punching assembly comprised of a base containing a slot and two chaff disposal openings, a first actuator adapted to actuate a first punch and to punch through the slot into a first chaff disposal opening, and a second actuator adapted to actuate a second punch and to punch through the slot into a second chaff disposal opening. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The invention will be described by reference to the following drawings, in which like numerals refer to like elements, and in which:  
         [0011]      FIG. 1  is a perspective view of a computer-to-plate assembly for use with the present invention;  
         [0012]      FIG. 2  is another perspective view of the assembly of  FIG. 1  wherein the plate punching assembly is illustrated;  
         [0013]      FIG. 3  is a depiction of one plate punching assembly of the present invention;  
         [0014]      FIG. 4  is an illustration of the footprint of the plate punching assembly of  FIG. 3 ;  
         [0015]      FIG. 5  is another illustration of the plate punching assembly of  FIG. 3 ;  
         [0016]      FIG. 6  is a schematic view of one plate punching assembly of the present invention;  
         [0017]      FIG. 7  is an illustration of one footprint for use with the present invention;  
         [0018]      FIG. 8  is an illustration of another footprint for use with the present invention;  
         [0019]      FIG. 9  is a depiction of another footprint for use in the plate punching assembly of the present invention;  
         [0020]      FIG. 10  shows yet another such footprint; and  
         [0021]      FIG. 11  is a schematic diagram of one method for collecting chaff. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]      FIG. 1  is a perspective view of a computer-to-plate assembly  100 . Assembly  100  is comprised of a cartridge receiver  102 , a registration area  104 , and an arm  110  equipped with a plate moving device  112  that is configured to move plates from cartridge receiver  102  to registration area  104 . The entire assembly  100  rests atop supporting structure  122 . For a disclosure of similar structures, reference may be had to U.S. Pat. No. 6,726,433 (apparatus for loading and unloading a supply of plates in an automated plate handler), the entire disclosure of which is hereby incorporated by reference into this specification.  
         [0023]     When a plate is disposed on registration area  104  it is properly positioned (i.e. “registered”) on registration area  104  in preparation for feeding the plate to imager  106 , wherein the plate will be imprinted with the desired image. Methods for registering plates are well known in the art. Reference may be had to U.S. Pat. No. 5,255,607(apparatus for maintaining registration when making a printing plate), U.S. Pat. No. 6,130,702 (method for reliable loading of unexposed printing plates), U.S. Pat. No. 4,566,194 (press plate positioning apparatus for automatic drawing machine), and the like. The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification. Once the plate is properly aligned, it is feed into the receiving rollers  200  (see  FIG. 2 ) of imager  106 .  
         [0024]      FIG. 2  is a perspective view of imager  106  in which the walls of imager  106  have been removed for the sake of simplicity of illustration. The imaged plate is passed through imager  106  by the action of rollers  200 . Rollers  200  are preferably precision nip rollers. Such precision nip rollers securely grip the imaged plate and can accurately control the motion of such plate. After imaging, the resulting plate is disposed within slot  202  of plate punching assembly  300 . By accurately controlling rollers  200 , the plate can be moved forward a predetermined distance and thereafter a first punch is made by assembly  300 . The plate can then be moved a second predetermined distance and thereafter a second punch is made. By repeating this process, any number of punches may be made at precise, predetermined locations.  
         [0025]     In one embodiment, the plate punching assembly  300  is disposed within imager  106 . In another embodiment, plate punching assembly  300  is disposed prior to the imager  106  (for example, after registration area  104 ). In yet another embodiment, the plate punching assembly  300  is disposed after, but external to, imager  106 .  
         [0026]     After one or more notches have been punched in the imaged plate, the plate is placed atop transporter  108 , which conveys the imaged plate to another processing device for eventual printing. The details of this transporter are disclosed in applicant&#39;s co-pending patent application U.S. Ser. No. 11/325,909, filed on Jan. 5, 2006, the content of which is hereby incorporated by reference into this specification.  
         [0027]      FIG. 3  is a perspective view of a plate punching assembly  300  that is comprised of base  305  and actuators  301 - 304 . In the embodiment depicted, actuators  301 - 304  are air actuators; these air actuators are known to those skilled in the art. Reference may be had, e.g., to U.S. Pat. No. 3,672,260 (compressed air actuator), U.S. Pat. No. 5,003,864 (geared air actuator), U.S. Pat. No. 5,161,502 (device for setting an idle air actuator), U.S. Pat. No. 5,454,254 (device with air actuator redraw mechanism), U.S. Pat. No. 5,941,509 (clamp assembly for air actuator), U.S. Pat. No. 6,513,418 (air actuator), U.S. Pat. No. 6,663,360 (internal air actuator valve), U.S. Pat. No. 6,679,160 (dual air actuator), and the like. The content of each of the aforementioned patents is hereby incorporated by reference into this specification.  
         [0028]     Referring again to  FIG. 3 , base  305  is comprised of slot  202 . Slot  202  is configured to permit a printing plate (not shown) to be disposed in such slot. Activation of one or more of the actuators  301 - 304  causes a punch (not shown in  FIG. 3 ) to punch a hole in the plate. The shape of the punch determines the shape of the resulting hole in the plate. Thus, by choosing which punch to use and selecting which locations on the pate to punch, a predetermined notching pattern can be formed.  
         [0029]      FIG. 4  shows plate punching assembly  300  from the bottom. From this perspective lower flange  405  of slot  202  is visible. As the plate emerges from rollers  200  (not shown in  FIG. 4 ), these flanges help to guide it into slot  202 . In the embodiment depicted, bearings  407  support the printing plate (not shown) at a specified distance away from the punch die block  715 . In one aspect of this embodiment, such printing plate is 0.040 inches away from such die block  715 ; and a spring assembly  409  holds the bearings  407  at the specified height (e.g., 0.040″). During the punching process, the printing plate (not shown) is pushed down onto the punch die block  715 .  
         [0030]     Referring again to  FIG. 4 , it will be seen that, also visible from this perspective, is footprint  714  of the base  305 . Footprint  714  is comprised of first chaff disposal opening  401 , second chaff disposal opening  402 , third chaff disposal opening  403 , and fourth chaff disposal opening  404 . It is advantageous that these chaff disposal openings  401 - 404  be in close proximity as this promotes the safe collection of the chaff.  
         [0031]      FIG. 5  illustrates plate punching assembly  300  from the backside. Plate punching assembly  300  is comprised of base  305 , actuators  301 - 304 , and linkage  500 . In the embodiment depicted, plate punching assembly  300  has four actuators  301 - 304 , each of which may be activated independently. In another embodiment, two such actuators are present.  
         [0032]     Independent activation of the actuators  301 - 304  is advantageous in that it permits the plate punching assembly  300  to punch a single hole in the plate, move the plate, and thereafter punch a second hole. Such a configuration ensures that the chaff disposal openings  401 - 404  (see  FIG. 4 ) are in close proximity—the plate moves to the location of the bore—thus the bores can be kept in a relatively compact arrangement. This compact arrangement permits easy collection of the chaff. In another embodiment, the activation of the actuators  301 - 304  is paired such that more than one, but fewer than all, of the actuators are activated at a given moment. For example, actuators  301  and  303  may be activated while actuators  302  and  304  remain dormant. In another embodiment, the actuators are activated independently, such that at least two actuators are used in a given punching cycle, but no more than one actuator is activated at a given moment. Such actuators  301 - 304  may be independently activated in any order. For example, in one embodiment actuator  301  is activated, the printing plate is subsequently moved and thereafter actuator  304  is activated. In another embodiment, actuator  302  and actuator  303  are independently activated in a similar fashion. In another embodiment, actuators  301 - 304  are each independently actuated in a given punching cycle. Other combinations of hole punching patterns will be appreciated by those skilled in the art after reading this specification. The punching of such holes is also illustrated in  FIG. 6 .  
         [0033]      FIG. 6  depicts a sectional profile of plate punching assembly  300  wherein the internal mechanisms are visible. In the embodiment depicted, actuator  301  is comprised of first air inlet  604  and second air inlet  606 . The actuator  301  is configured to actuate punch  701 , thus punching through slot  202  and into chaff disposal opening  401 . Actuator  301  is mechanically connected to linkage  500  such that their motions are coupled. Activation of actuator  301  by first air inlet  604  causes the actuator to move in first horizontal direction  600  for a certain air cylinder stroke distance. This motion causes linkage  500  to move which, in turn, causes punch  701  to travel in first vertical direction  602  for a certain punch stroke distance, thus punching through slot  202  and into first chaff disposal opening  401 . In one embodiment, the air cylinder stroke distance is about 0.8 inches and the punch stroke distance is about 0.1 inches. In such an embodiment, the stroke ratio, which is the punch stroke distance divided by the air cylinder stroke distance, is 0.125. In another embodiment, the stroke ratio is from about 0.1 to about 5. In another embodiment, the stroke ratio is from about 0.1 to about 1. To reset bore  701 , actuator  301  is activated by second air inlet  606  that causes the actuator to move in second horizontal direction  601 . This causes the linkage  500  to move bore  701  in second vertical direction  603 , thus returning bore  701  to its original position. As will be apparent to one skilled in the art, the linkage  500  provides a mechanical advantage which increases the force that is delivered by punch  701 .  
         [0034]     Prior to the activation of the punch  701 , a plate is disposed in slot  202  through slot opening  710 . As depicted in  FIG. 2 , the plate enters slot  202  from the side of slot opening  710 . In one embodiment, slot  202  extends only partially into base  305 , and thus has an inner slot edge  700 . In another embodiment, the slot  202  runs the entire depth of base  305 . Other slot configurations are illustrated in  FIG. 7  and  FIG. 8 .  
         [0035]      FIG. 7  depicts footprint  714  of base  305  (see  FIG. 4 ) wherein plate  716  (shown in phantom) is disposed in slot  202  (see  FIG. 4 ). Footprint  714  has depth  708  and length  706 . In one embodiment, length  706  is less than about 40 centimeters. In another embodiment, the length  706  is less than about 25 centimeters. In yet another embodiment, the length  706  is from about 14 centimeters to about 20 centimeters. In the embodiment depicted, first punch  701 , second punch  702 , third punch  703 , and fourth punch  704  are co-linear such that they form punch line  712 . It is desirable that punch line  712  be parallel to inner plate edge  705 . In the embodiment depicted, the inner plate edge  705  of plate  716  is contiguous with inner slot edge  700 . The resulting plate will have holes within the center of plate  716 .  
         [0036]     In another embodiment, shown in  FIG. 8 , the inner plate edge  705  is not contiguous with inner slot edge  700 , but punch line  712  is still parallel to inner plate edge  705 . The resulting plate will have notches on the edge of plate  716 . In yet another embodiment, the inner plate edge  705  is not contiguous with inner slot edge  700 , but the holes will be within the center of plate  716 . Reference may be had to  FIG. 9 .  
         [0037]     Referring to such  FIG. 9 , and in the embodiment depicted therein, first punch  701  has a shape substantially different from second punch  702 . Utilizing punches of various shapes permits several notching patterns to be made on the resulting plates. Should the user desire to produce additional notching patterns, the user may either add additional actuators and/or switch an existing punch for an alternate punch.  
         [0038]      FIG. 10  is a depiction of footprint  714  that is similar to the footprint depicted in  FIG. 8  except in that chaff disposal openings  403  and  404 , as well as punches  702  and  703 , have been moved away from inner slot edge  700 . Such a configuration allows the user to punch two holes on the edge of plate  716  (with punches  701  and  704 ) and also punch two holes that are not on the edge of plate  716  (with punches  702  and  703 ). In such embodiments, at least two punches (such as punches  701  and  704 ) pass through first punch line  1000 , which is parallel to inner plate edge  705 . At least two additional punches (such as punches  702  and  703 ) pass through second punch line  1002 . In the embodiment depicted, first punch line  1000  and second punch line  1002  are parallel. First punch line  1000  is a first distance away from inner plate edge  705 . In the embodiment depicted, this first distance is substantially zero and the resulting hole is on the edge of plate  716 .  
         [0039]     Other measurements of the first distance are also contemplated for use with this invention. Second punch line  1002  is a second distance  1004  away from inner plate edge  705 , such that the second distance is greater than the first distance. In this manner, the resulting hole is not on the edge of plate  716 . In another embodiment, not shown, such first and second punch lines are not parallel.  
         [0040]     One advantage of the plate punching assembly  300  is the safe and easy collection of the chaff produced during the punching process. Since the assembly of the present invention is substantially more compact than prior art assemblies, the entire footprint  714  (see  FIG. 7 ) may be disposed over a collection shaft that terminates in a collection container. Reference may be had to  FIG. 11 .  
         [0041]      FIG. 11  is an illustration of the computer-to-plate assembly  100  of  FIG. 1  from the rear. Plate punching assembly  300  has been disposed over collection shaft  1100 . Collection shaft  1100 , which is disposed within supporting structure  122  (see  FIG. 1 ) terminates in collection container  1102 . Container  1102  has viewing ports  1104  that permit the user to determine if the container is full of chaff. Container  1102  is disposed external to supporting structure  122  (see  FIG. 1 ) and can be removed from such supporting structure  122  and emptied without interrupting the operation of assembly  100 . In one embodiment, the entire path of the chaff is sealed such that no chaff has any opportunity to escape and interrupt the operation of assembly  100 .  
         [0042]     It is therefore, apparent that there has been provided, in accordance with the present invention, a method and apparatus for punching a notch in a printing plate. While this invention has been described in conjunction with preferred embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.