Abstract:
A non-contact cutter for a polymer corner protector disposed on a load includes an air manifold having an inlet and an outlet and defining an air passage and a heating element disposed at least in part in the air passage. A compressed gas is communicated to the manifold and into the air passage for intimate contact with the heating element to heat the gas. The heated gas is discharged through the outlet to contact and soften the polymer corner protector at a desired location to separate the corner protector at the desired location. A system and method for non-contact cutting are disclosed.

Description:
CROSS-REFERENCE TO RELATED APPLICATION DATA 
     This application claims the benefit of priority of provisional U.S. Patent application Ser. No. 61/089,604, filed Aug. 18, 2008. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a cutter for edge protectors for bulk loads. More particularly, the present invention relates to a non-contact cutter for edge protectors that are used on large loads, such a bricks and masonry. 
     Typically, large loads such as bricks packaged as a plurality of stacked individual units formed into a 3-dimensional bundle. The bundle typically includes corner protectors that extend along the edges of the bundle and straps that encircle the load and the corner protectors. The corner protectors are elongated angle members that fit onto the corner of the load. One know corner protector is the BladeRunner™ edge protector commercially available from ITW Signode of Glenview, Ill. The corner protectors can be, for example, formed as a 2 inch by 2 inch wide, poly element having a thickness of about 0.014 to about 0.036 inches (about 14 to 36 mils) and are typically provided in roll form having a length of about 1000 to about 3000 feet. 
     During the bundling process, the corner elements are often required to be cut to conform to the size of the load. To effect this cut, the protectors are perforated (transverse to the length) and the protector is pulled or torn to separate the protector portion on the load from the remaining portion. This has its drawbacks. In particular, if the protector does not separate readily the bundle can be pulled over or the protector can be pulled from the load. Both of these situations are preferably avoided. 
     Accordingly, there is a need for a cutter for the edge protector. Desirably, such a cutter is a non-contact cutter. More desirably, such a cutter is automatically actuated and can cut known corner protectors in a manner that does not compromise the integrity of the protector element or potentially affect the stability of the load. 
     BRIEF SUMMARY OF THE INVENTION 
     A non-contact cutter for a polymer corner protector disposed on a load includes an air manifold having an inlet and an outlet and defining an air passage and a heating element disposed at least in part in the air passage. A compressed gas, such as air, is communicated to the manifold and into the air passage for intimate contact with the heating element to heat the gas. The heated gas is discharged through the outlet to contact and soften the polymer corner protector at a desired location to separate the corner protector at the desired location. 
     In one embodiment, the non-contact cutter includes a housing having a heating element disposed therein. The air manifold is disposed at least in part in the housing. The housing can have a generally L-shaped body having a back and a leg. In such an arrangement, the heating element is disposed at least in part in the back and leg, and the air passage includes a portion configured to direct air to the back and leg for intimate contact with the heating element. 
     A preferred heater is an electric heater. Alternately, the heater can be a ceramic heater. 
     The cutter can be disposed in a head and such that the head is movable toward and away from the polymer corner protector. The head can be mounted to a carriage and operably mounted to a rail for linear movement toward and away from the corner protector. Alternately, the head can be mounted for pivotal movement toward and away from the corner protector. 
     A system and method for non-contact cutting are also disclosed. 
     These and other features and advantages of the present invention will be readily apparent from the following detailed description, in conjunction with the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The benefits and advantages of the present invention will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings, wherein: 
         FIG. 1  is a perspective view of load of bricks in a bundling apparatus showing an embodiment of a corner edge protector cutting system embodying the principles of the present invention; 
         FIG. 2  is a front view of the load in the apparatus of  FIG. 1  with the cutting system in the home position; 
         FIG. 3  is a view similar to  FIG. 2  with the cutting system in the cutting position; 
         FIG. 4  is a perspective view of a cutting head; 
         FIG. 5  is a front view of a load of bricks in the bundling apparatus showing an alternate embodiment of the corner edge protector cutting system; 
         FIG. 6  is a front view of the load in the apparatus of  FIG. 5  with the cutting system in the home position; 
         FIG. 7  is a view similar to  FIG. 6  with the cutting system in the cutting position; and 
         FIG. 8  is a sectional view of the cutting head of the alternate embodiment taken along line  8 - 8  of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiment illustrated. 
     It should be further understood that the title of this section of this specification, namely, “Detailed Description Of The Invention”, relates to a requirement of the United States Patent Office, and does not imply, nor should be inferred to limit the subject matter disclosed herein. 
     Referring now to the figures and in particular to  FIG. 1 , there is shown a bundled load of bricks L on a bundling apparatus A having an embodiment of a corner edge protector cutting system  10  in accordance with the principles of the present invention. The bundling apparatus A includes a strapping section (not shown) at which strapping material S is positioned around the load L and the corner edge protectors E. The load L is conveyed though the bundling apparatus A on a conveyor  12 . 
     In order to separate the load L into separate sections C, the corner edge protectors E must be cut. The corner edge protector cutting system  10  includes a frame  14  having multiple cutting heads  16   a - d  positioned on the frame  14 . 
     In a present system, four cutting heads  16   a - d , one positioned at each corner of the load L, are positioned on the frame  14 . The frame  14  essentially forms an arch  18  over the conveyor  12 . The frame  14  and the location of the heads  16   a - d  on the frame  14  are all adjustable to accommodate different conveyor widths w 12  and heights h 12  and load L widths w L  and heights h L . 
     Each head  16   a - d  includes a heat torch  20  for cutting the edge protector E material. The heat torch  20  includes electric controls  22  and pneumatic controls  24 . A present heat torch  20  heats air using a ceramic heating element (not shown). In a present torch  20 , the heating element is a 4250 watt ceramic heating element. The heat torch  20  discharges the heated air to an angled nozzle  26  that conforms to the corner N of the load L (that is, a 90 degree angled nozzle  26 ). The nozzle  26  includes a series of openings or holes  27  on the underside  28  through which the heated air passes. Air is blown through the inside  29  of the torch  20  where it is heated to about 1200 deg. F. after which the air passes through the nozzles  26 . 
     The torches  20  are mounted to the frame  14  on a pivot mount  30 . A present cutting head  16  uses a pneumatic cylinder  32  to pivot the torch  20  and nozzle  26  between the home and cutting positions ( FIGS. 2 and 3 ). In the home position ( FIG. 2 ) the cutting heads  16   a - d  are fully pivoted out of the path of the load L and in the cutting position ( FIG. 3 ) the torches  20  and nozzles  26  are pivoted such that the nozzles  26  are within about ½ inch of the edge protector E. When the torches  20  are actuated, the heated air exiting the nozzles  26  cuts the corner protector E (by melting the protector material). The brick or block load section C can then be separated from the load L. In a present cutting system  10 , the non-contact cutter  10  cuts the corner protector E without physically contacting or exerting any undue physical force on the corner protector E material. Advantageously, the heat cutting does not significantly, if at all, adversely effect the integrity of the protector E material. In fact, it is believed that eliminating any physical contact cutting will be shown to enhance the structural integrity of the material. 
     An alternate embodiment of the cutting system  110  is shown in  FIGS. 6-8 . In this embodiment  110  the upper cutting heads  116   a - b  are suspended on carriages  134  from an upper beam  136 . The carriages  134  move laterally (horizontally, as indicated by the arrow at  138 ) toward and away from the load L. The carriages  134  are driven by a spring. The carriages  134  are set in an approximate location (since the width w L  of the loads L does not vary greatly). The heads  116   a,b  are set on rollers (not shown) that ride in a track  139  in the carriage  134 . The heads are spring (not shown) biased inward, toward the center of the load L. Inward over-travel of the heads  116   a,b  is prevented by bumpers  141  on the carriages. As the heads  116   a,b  move downward (discussed below), a ramped contact surface  143  on the head  116   a,b  contacts the load corner N and urges the head  116   a,b  outward to properly position itself relative to the edge protector E. Outward over-travel of the heads  116   a,b  is also prevented by bumpers  145  positioned on the carriages  134 . 
     The upper heads  116   a,b  are suspended on rails  140  from the carriages  134  to move vertically (up and down, as indicated by the arrow at  142 ) toward and away from the load L. Vertical movement of the heads  116   a,b  is provided by cylinders  144  mounted to the carriages  134  and the heads  116   a,b.    
     The lower heads  116   c,d  are also mounted on rails  146  for horizontal movement (as indicated by the arrow at  148 ). However, because the lower periphery (bottom) of the load L is at the same height regardless of the size of the load, the heads  116   c,d  only need to be mounted for horizontal movement (e.g., vertical movement is not needed). The heads  116   a,b  are driven, horizontally, by cylinders  150  toward and away from the load L. Spring mountings (not shown) on the lower heads  116   c,d  permit the heads  116   c,d  to move slightly downward in the event that the head  116   c,d  encounter an obstruction. 
     The upper and lower heads  116  are configured in a similar manner, an exemplary one of which  116   c  is shown in  FIG. 8 . The head  116  includes an outer housing  152  and inner chamber  154 . The housing  152  has an L-shape with a back  156  and leg  158  being about symmetrical. The chamber  154  includes a heating element portion  160  and an air passage  162 . A heating element  164  is positioned in the heating element portion  160  and extends into the back  156  and leg  158 , extending about the periphery of the outer and inner sides (indicated at  166 ,  168 ) of the back  156  and leg  158 . 
     In this embodiment  110 , the heating element  164  is an electric element, and specifically, a 350 watt tubular heating element. 
     The air passage  162  has an inlet nozzle  170  in communication with a cross-flow passage  172  that opens into the heating element portion  160  near the terminal ends  174  of the heating element  164 . The air passage  162  then continues through (or with) the heating element portion  160  and opens into a discharge or outlet region  176  at the interior of the L-shape (the inner walls  178  of the back  156  and leg  158 ). The location of the air passage inlet  170  and outlet  176  and the comingling of the air passage  162  and the heating element portion  160  brings the air into intimate contact with the heating element  164  so as to heat the air. The outlet  176  can be formed as a thin open passage, a series of openings or other discharge configuration. The air exits the discharge at a temperature of about 450° F. The heated air softens the corner protector E material so that the load section C (and protector E material) can be separated from the load L for handling. In this embodiment, the exit opening or passage  176  is a narrow slot  180 , having a width of about 10 thousandths of an inch (10 mils) and is positioned about 0.125 (⅛) inches from the corner protector E during operation. The heads  116   a - d  include positioning contacts or bumpers  182  to contact the load L outside the edge protectors E to properly position the heads  116   a - d  for cutting. 
     It will be appreciated by those skilled in the art that the underlying principle, that is the use of heated gas (e.g., air), is the same in both embodiments of the corner edge protector cutting system  10 ,  110 . In both embodiments, a gas stream (e.g., and air stream) is heated and is expelled via a manifold through a reduced area exit region in the direction of the corner protector E. The exit or discharge  27 ,  180  is maintained in close proximity to the corner protector E, sufficient to heat the corner protector E to softening, to separate. In this manner the corner protector E is cut or separated without physically contacting the protector E with a bladed cutting tool. Rather, the heated air stream has been found to be effective in promoting the separation of the corner protector E at the load L/section C separation, without adversely affecting the strength or integrity of the corner protector E. 
     All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure. 
     In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular. 
     From the foregoing it will be observed that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated is intended or should be inferred. The disclosure is intended to cover all such modifications as fall within the scope of the invention.