Abstract:
A method and apparatus for securing a cable tie about an object is described. Further, a relatively compact banding tool that facilitates cable tie tensioning is described.

Description:
[0001]    This application is a Continuation-In-Part of U.S. patent application Ser. No. 14/685,330, filed Apr. 13, 2015, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/990,339, filed May 8, 2014, the entirety of which is incorporated by reference herein. 
         [0002]    This application also claims the benefit of U.S. Provisional Patent Application Ser. No. 62/239,635, filed Oct. 9, 2015, the entirety of which is incorporated by reference herein. 
         [0003]    This application is related to U.S. Pat. Nos. 5,566,726 and 4,896,402, the entire disclosures of which are incorporated by reference herein. 
         [0004]    This application is also related to U.S. Patent Application Publication No. 2013/0199382, the entirety of which is incorporated by reference herein. 
     
    
     FIELD OF THE INVENTION 
       [0005]    Embodiments of the present invention relate to a method and apparatus for securing a cable tie about an object, and in particular, to a relatively compact banding tool that facilitates cable tie tensioning. 
       BACKGROUND OF THE INVENTION 
       [0006]    Cable ties, which are sometimes referred to as “band clamps,” are typically used to bundle wires, secure back shells to cables, secure heat shields to pipes, and secure signage to poles. Cable ties are generally comprised of a band with an interconnected head that secures a free end of the band after a predetermined band tension has been applied. Some bands have had operatively interconnected heads (or buckles or seals), instead of an integrated head. 
         [0007]    Tensioning tools are used to tighten cable ties. For example, the tensioning tool described in U.S. Pat. No. 5,566,726 employs a band gripping mechanism (also denoted a “tension block”) that repeatedly grips and incrementally moves a portion of the band, which tensions the band. More specifically, to tension the band, the tension block is first moved along a length of the band in a first direction, generally toward objects being banded, e.g. wires. The tension block then engages the band and moves a portion of the same away from the objects being banded which incrementally tensions the band. The tension block grips the band with a pin having an axis that is oriented along the width of the band. The pin may be biased by a spring, or other biasing device, to ensure firm engagement with the band when the tension block is pulled away from the objects being banded. After the tension block has moved its full extent away from the objects being banded, the tension block is released from the band so that it can be moved to another location on the band to begin another incremental tension cycle. Band tension is maintained by a front gripper that selectively contacts the band between the tension block and the objects being banded when the tension block is moved from one location on the band to another. 
         [0008]      FIG. 1  shows a band tensioning tool  2  of the prior art and illustrates the tensioning steps described above. Here, the tension block  6  is shown with the front gripper  10  spaced therefrom. The band  14  is positioned through the tension block  6  and the front gripper  10 . The tension block  6  includes a proximal end  18 , which is closer to the objects being banded  22 , and a distal end  26 . The dashed outline of the tension block  6  represents the movement of the proximal end  18  towards the objects  22 . The tension block  6  further includes a platform  30  that supports the band  14  as it passes through the tension block  6 . The tension block  6  also includes a lateral opening  34  that inclines toward the platform  30  toward the proximal end  18  of the tension block  6 . The tension block  6  further includes a gripping pin (or gripper)  38  that is operatively positioned and movable within the lateral opening  34 . The pin  38  is biased by a biasing member (not shown) that moves the gripping pin  38  in the direction of arrow  40  to firmly engage the band  14 . When the tension block  6  moves in the direction of arrow  44 , the gripping pin  38  is not biased and is able to slide on the surface of the band  12 . However, when the tension block  6  is moved away from the objects  22  (i.e., in the direction of arrow  48 ), the gripping pin  38  moves toward a proximal end  52  of the lateral opening  34  and frictionally engages and grips the band  14 . 
         [0009]    The front gripper  10  also includes an inclined lateral opening  56  and a gripping pin  60  that moves within the opening  56 . The gripping pin  60  is biased toward a proximal end  64  of the opening  56 . When the tension block  6  is not tensioning the band  14 , i.e., moving in the direction of arrow  44 , the gripping pin  60  of the front gripper  10  frictionally engages the band  14  so that it is not slackened by a band tension counterforce acting in the direction of arrow  68 . Once the tension block  6  has completed its movement toward the front gripper  10 , it reverses direction, thereby causing the gripping pin  38  to securely engage the band  14  and pull it in the direction of arrow  48 . Movement of the band  14  in the direction of arrow  48  causes the gripping pin  60  to disengage from the band  16 , thereby allowing the band  14  to be pulled into the band tightening tool  2 . 
         [0010]    Tensioning tools often employ a device for firmly interconnecting the band to the head and a device for severing the excess band from the tensioned cable tie. Some tools combine this functionality. For example,  FIG. 2  shows the interconnection of the blade  70  to a tool head  74 . Here, the prior art blade  70  is shown rotatably interconnected to the tool head  74  via a pin  78  attached to sidewalls of the tool head  74 . Forces acting on the blade  70 , which are generated by the knife  82 , will be reacted by the pin  78 . Forces will also be transmitted through the pin  78  to the sidewalls of the tool head, which often weakens or damages the same. 
         [0011]    Again, after the tension block and the front gripper perform their respective duties, the band is severed and clamped, i.e., locked to a buckle or seal. A stationary blade is provided beneath the front gripper and a movable knife is provided forward of the front gripper. The knife moves relative to the blade to sever a band located therebetween. More specifically, once the desired band tension is achieved, a linkage is used to move the knife closer to the blade which compresses the band and eventually severs the same. The gap between the knife edge and the blade edge is preferably maintained within a predetermined tolerance that will ensure bands are cut in the most effective manner, even after many cutting cycles. 
         [0012]    One drawback of prior art tensioning tools is that downward pressure from the knife is transmitted through the band and to the blade, which stresses the blade and adversely affects its effectiveness. Band cutting is also adversely affected because the blade edge is spaced from the blade&#39;s attachment point, i.e., the location where pressure acting on the blade&#39;s cutting edge is reacted. Over time, the blade may be prone to flex, which can lead to fatigue and ultimately failure. 
         [0013]    One of ordinary skill in the art will appreciate that cutting will eventually weaken the blade and cause it to yield or fracture. Unfortunately, the failure rate and mode is unpredictable, wherein the blade may fail after 100, 200, or 1000 bands are tensioned. When blades fail, the tools are shipped from the end user to the factory for blade or knife replacement, which is expensive, costly, and time consuming. 
         [0014]    As alluded to above, blade support of prior art tools is not ideal and blade damage is common. The primary failure mode is blade edge degradation and, in some instances, fracture. More specifically, the blade of prior art tools is rotatably interconnected to a tool head. Further, the blade of some prior art tools possesses an internal non-cutting edge that engages the tool head to react loads generated at an external cutting edge of the blade when the knife contacts the band positioned between the knife and the blade. This complex design came from a desire to provide a blade with two edges such that when one was damaged, the blade could be removed and rotated to locate the previously non-used blade adjacent to the knife. 
         [0015]    Another drawback of prior art tensioning tools is that the knife does not travel in a smooth, continuous manner, thus a gap between the knife and the blade is not consistent, which affects cutting performance and can increase blade loads. For example, if the space between the knife&#39;s cutting edge and the blade&#39;s cutting edge is too wide, knife travel may be inadequate to sever the band as material will deform between the knife edge in the blade edge. If the gap is too narrow, excess loads generated by the knife will be transferred to the blade and cause damage. 
         [0016]    In view of the foregoing, there exists a need for a banding tool that maintains tolerance between the knife and blade, which increases blade life. 
       SUMMARY OF THE INVENTION 
       [0017]    In accordance with one aspect of the invention, a band tensioning tool is provided that includes a tensioning mechanism having a first longitudinal axis therethrough. The tensioning mechanism comprises a force storing device within a tool handle. A tension adjustment plunger, a tension adjustment screw, and a connecting rod are interconnected to the force storing device and to tension transferring device. In one embodiment, the force storing device is a compression spring that is pre-compressed to a desired amount by the adjustment plunger. 
         [0018]    The tension transferring device comprises a tension transfer lever interconnected to the tensioning device and a tensioning block. At least one push link is connected on a first end thereof to the tensioning device, and on a second end to a lever arm. The tension block, which has an elongated slot and a tension pin, is connected to the lever arm, wherein the tension block pulls the band into tension. 
         [0019]    It is still yet another aspect the present invention to provide a knife with an arcuate cutting edge and a head deformation edge. More specifically, the cutting edge of one embodiment of the present invention initially contacts the band and is used with the blade to sever the band. Thereafter, the deformation edge of the knife is adapted to contact the cable tie&#39;s locking feature, e.g., the cable tie head, and deforms the same. Deforming the head will change its geometry and, thus, change its moment of inertia and strength. As the head is designed to maintain band tension, those of ordinary skill in the art will appreciate that increased head stiffness will maximize the cable tie&#39;s retained force. The knife of one embodiment of the present invention also removes sharp corners and provides a smooth cut, which is desirable for safety. 
         [0020]    Tools of embodiments of the present invention are designed to tension and secure various types of band clamps and cable ties. Some versions of the contemplated tool are suited to secure cable ties commonly sold by the assignee of the instant application under the trademark Tie-Dex, which are described in U.S. Pat. No. 4,896,402. As one of skill the art will appreciate, it is often desirable to reduce cable tie weight, which can be accomplished if tie thickness is reduced. Accordingly, it is one aspect of embodiments of the present invention to provide a cable tie of reduced thickness made of tempered stainless steel. In applications where a reduced diameter banding is required, the thinner band will perform better than the current cable ties. 
         [0021]    Existing tools often have difficulty in cutting thinner cable ties. More specifically, because of tolerance stack between the cutter knife (moving portion) and the blade (stationary portion), the gap between the two components that affect cutting may vary over time. Often, the gap will generally increase over time and the cable tie will deform instead of severing as a knife passes the blade. It is thus another aspect of the present invention to control the distance between the blade&#39;s cutting surface and the knife. By maintaining a tight tolerance between these two components, thinner bands can be formed and severed without bending. 
         [0022]    One embodiment of the present invention achieves this goal of maintaining tight tolerances by including a blade with an integrated knife housing. The knife housing includes a channel that slidingly receives the knife. In this fashion the tolerance between the knife and the blade is maintained because the knife&#39;s movement is limited by the knife channel. The blade edge also interacts with a load point that is near the blade edge, which reduces damaging loads acting on the blade. Furthermore, by maintaining the tolerance between the knife and the blade edge, the gap between these two components can be maintained after many uses. 
         [0023]    The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. That is, these and other aspects and advantages will be apparent from the disclosure of the invention(s) described herein. Further, the above-described embodiments, aspects, objectives, and configurations are neither complete nor exhaustive. As will be appreciated, other embodiments of the invention are possible using, alone or in combination, one or more of the features set forth above or described below. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions. 
           [0025]      FIG. 1  is a cross sectional view showing a band tensioning device of the prior art; 
           [0026]      FIG. 2  is a cross sectional view showing a knife and blade of the prior art; 
           [0027]      FIG. 3  is a side elevation view of one embodiment of the present invention; 
           [0028]      FIG. 4  is a bottom perspective view of  FIG. 3 ; 
           [0029]      FIG. 5  is a side elevation view opposite to that of  FIG. 3 ; 
           [0030]      FIG. 6  is another bottom perspective view; 
           [0031]      FIG. 7  is a cross-sectional view of one embodiment of the present invention; 
           [0032]      FIG. 8  is a partially exploded view of one embodiment of the present invention; 
           [0033]      FIG. 9  is a top perspective view of one embodiment of the present invention; 
           [0034]      FIG. 10  is a detailed view of a blade of one embodiment of the present invention; 
           [0035]      FIG. 11  is a perspective view showing the blade and knife one embodiment of the present invention; 
           [0036]      FIG. 12  is a perspective view of the blade of one embodiment of the present invention; 
           [0037]      FIG. 13  is a cross-sectional view of the blade of one embodiment a present invention; 
           [0038]      FIG. 14  is a perspective view showing the knife of one embodiment of the present invention; 
           [0039]      FIG. 15  is an alternative embodiment of the present invention in which the banding tool is a pneumatic device; 
           [0040]      FIG. 16  is a partial top perspective view of a band tensioning device of another embodiment of the present invention; 
           [0041]      FIG. 17  is a partial front perspective view of the band tensioning device of  FIG. 16 , wherein the knife is in a first, retracted position of use; 
           [0042]      FIG. 18  is a partial front perspective view of the band tensioning device of  FIG. 16 , wherein the knife is in a second, cutting position of use; 
           [0043]      FIG. 19  is a front perspective view of a calibration tool used with the band tensioning device of one embodiment of the present invention; 
           [0044]      FIG. 20  is a front perspective view of a calibration tool used with the band tensioning device of one embodiment of the present invention; 
           [0045]      FIG. 21  is a detailed partial perspective view showing a band in the calibration tool; 
           [0046]      FIG. 22  is a front perspective view of a calibration tool interconnected to a band tensioning tool; and 
           [0047]      FIG. 23  is a cross sectional view of  FIG. 21 . 
       
    
    
       [0048]    To assist in the understanding of one embodiment of the present invention the following list of components and associated numbering found in the drawings is provided herein: 
         [0000]    
       
         
               
               
             
               
               
             
           
               
                   
               
               
                 # 
                 Component 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 2 
                 Band tensioning tool 
               
               
                 6 
                 Tension block 
               
               
                 10 
                 Front gripper 
               
               
                 14 
                 Band 
               
               
                 18 
                 Proximal end 
               
               
                 22 
                 Objects 
               
               
                 26 
                 Distal end 
               
               
                 30 
                 Platform 
               
               
                 34 
                 Lateral opening 
               
               
                 38 
                 Gripping pin 
               
               
                 52 
                 Proximal end 
               
               
                 56 
                 Lateral opening 
               
               
                 60 
                 Gripping pin 
               
               
                 64 
                 Proximal end 
               
               
                 70 
                 Blade 
               
               
                 74 
                 Tool head 
               
               
                 78 
                 Pin 
               
               
                 82 
                 Knife 
               
               
                 100 
                 Banding tensioning tool 
               
               
                 104 
                 Head 
               
               
                 108 
                 Handle 
               
               
                 112 
                 Tension handle 
               
               
                 116 
                 Cutoff handle 
               
               
                 120 
                 Hook 
               
               
                 124 
                 Blade 
               
               
                 128 
                 Knife 
               
               
                 132 
                 Front gripper 
               
               
                 136 
                 Spring 
               
               
                 140 
                 Rod 
               
               
                 144 
                 Transfer lever 
               
               
                 148 
                 Tension block 
               
               
                 152 
                 Gripper 
               
               
                 156 
                 Band 
               
               
                 160 
                 Cutter arm 
               
               
                 164 
                 Housing 
               
               
                 168 
                 Knife channel 
               
               
                 172 
                 Channel 
               
               
                 176 
                 Blade edge 
               
               
                 180 
                 Cutting Edge 
               
               
                 184 
                 Deformation Edge 
               
               
                 200 
                 Pneumatic tool 
               
               
                 300 
                 Band tensioning tool 
               
               
                 304 
                 Head 
               
               
                 306 
                 Handle 
               
               
                 312 
                 Tension handle 
               
               
                 316 
                 Cutoff handle 
               
               
                 324 
                 Blade 
               
               
                 328 
                 Knife 
               
               
                 332 
                 Front gripper 
               
               
                 370 
                 Blade housing 
               
               
                 372 
                 Channel 
               
               
                 374 
                 Protrusion 
               
               
                 378 
                 Recess 
               
               
                 382 
                 Cutter link 
               
               
                 400 
                 Calibration device 
               
               
                 404 
                 Gauge body 
               
               
                 408 
                 Hook 
               
               
                 412 
                 Slot 
               
               
                 416 
                 Magnet 
               
               
                 420 
                 Distal end 
               
               
                 424 
                 Plate 
               
               
                 428 
                 Screw 
               
               
                 432 
                 Aperture 
               
               
                 436 
                 Stop 
               
               
                 440 
                 Stationary arm 
               
               
                 444 
                 Movable arm 
               
               
                 446 
                 Band head 
               
               
                 448 
                 Proximal end 
               
               
                 452 
                 Adjustment screw 
               
               
                 456 
                 End 
               
               
                 460 
                 Opening 
               
               
                 464 
                 Band 
               
               
                 468 
                 Forward opening 
               
               
                 472 
                 Rear opening 
               
               
                 478 
                 Inner surface 
               
               
                   
               
             
          
         
       
     
         [0049]    It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. 
       DETAILED DESCRIPTION 
       [0050]      FIGS. 3-6  show a banding tool  100  of embodiments of the present invention that is designed to tension and secure a band clamp comprising a band and a band locking head. The banding tool  100  includes a head  104  interconnected to a handle  108 . A tension handle  112  and a cutoff handle  116  are rotatably interconnected to the head  104  and move relative to the handle  112 . A hook  120  is also rotatably interconnected to the head  104  and is adapted to fix the tension of a band inserted into the head  104 . The head  104  also accommodates a blade  124  that is operatively associated with a knife  128 . As in the existing banding tools, a front gripper  132  is used to tension the band by operation of the tension handle  112 . The operation of this embodiment of the present invention is a very similar to that shown and described in U.S. Pat. No. 5,566,726 mentioned above. 
         [0051]      FIGS. 7 and 8  show the inner workings of one embodiment of the present invention. The handle  108  includes a spring  136  that is positioned about a rod  140 . The rod  140  cooperates with a transfer lever  144  to dictate the amount of tension that can be applied to the band. In operation, the tension handle  112  is cycled toward and away from the handle  108  to move a tension block  148  and a gripper to tension the band  156 . Again, the spring  136  position within the handle  108  will dictate the maximum tension that can be applied to the band as discussed in U.S. Patent No. 5,566,726. Once the desired tension is achieved, the hook  120  is moved toward the handle  108  to lock the band at the desired tension. The cutoff handle  116  then is rotated towards the handle  108  which rotates the cutter arm  160  and moves the knife  128  downwardly to sever the band  156 . Again, the mechanism contemplated by this embodiment of the present invention is similar to the Applicant&#39;s patents mentioned above. 
         [0052]      FIGS. 9-13  show the improved blade  124  and knife  128  of some embodiments of the present invention. More specifically, the blade of the prior art is replaced by a housing  164 , that is statically interconnected to the head  104 . The housing  16  includes the blade  124  with and integrated knife channel  168 . The knife channel  168  may have a square profile that prevents significant rotation of the knife  128  within the knife channel  168 . The blade  124  also includes a channel  172  for receipt of the band. As shown in  FIG. 13 , the band channel  168  is adapted to receive a band such that the blade edge is positioned beneath the band and a knife  128  is positioned above the band. 
         [0053]    Referring to  FIG. 11 , in operation, when the cutoff handle  116  is actuated, the cutter arm  160  rotates along arrow  180 , which moves the knife  128  downwardly along arrow  184  to sever the band. As described in detail below, this configuration maintains a tolerance between the blade edge and the knife  128  such that stainless steel bands can be severed. 
         [0054]      FIG. 14  shows the knife  128  of one embodiment of the present invention that includes a cutting edge  180  and a deformation edge  184 . That is, knife  128  may employ an arcuate cutting edge  180  and a cable tie head deformation edge  184 . The cutting edge  180  initially contacts the band and is used with the blade to sever the band. Thereafter, the deformation edge  184  contacts the cable tie&#39;s locking feature, e.g., the cable tie head, and deforms the same. 
         [0055]    As one of ordinary skill will appreciate, the tool described herein can be made to operate pneumatically as shown in  FIG. 15 . More specifically, the tensioning arm and cutoff handle can replace by a pneumatic system  200  such that pneumatic forces are used to operate the tension block and other associated components described herein. Such systems are described in the Applicant&#39;s patent described above. 
         [0056]      FIGS. 16-18  show a band tensioning tool  300  of another embodiment of the present invention. Here, the knife  328  and associated components are made thinner to accommodate bands or reduced width. As in the embodiments provided above, the knife  328  travels in a channel provided in a blade housing  370 . Because the knife  328  is of a reduced profile, it is impossible to provide a pin/clevis interconnection between a cutter arm  360  and the knife  328 . 
         [0057]    To address this issue, the cutter arm  360  is provided with a protrusion  374  operatively engaged within a recess  378  provided in the knife  328 . The protrusion  374  is designed to travel within the recess when the cutter arm  360  is moved. Again, the knife is moved downwardly by rotation of the cutter arm  360  wherein an edge of the knife cooperates with the blade  324  to sever the band. The operation of one embodiment of the present invention is shown in  FIG. 18 . Here, when a cutoff handle (See  116  of  FIG. 3 ) is moved, a cutter link  382  moves in the direction of arrow A. The cutter link  382  rotates the cutter arm  360  in the direction of arrow B which forces the protrusion  374  to move downwardly. The protrusion riding in the recess  378  moves the knife  328  downwardly wherein an edge thereof cooperates with an edge of the blade  324  to sever a band. Moving the cutter arm  360  in opposite direction moves the cutter links  382  back into the tool head  304 , which rotates the cutter arm  360  and protrusion  374  to retract the knife back into the blade housing  370 . 
         [0058]    As one of ordinary skill in the art will appreciate, is often desirable to periodically check and adjust the tension output of the tools described above. That is, it is necessary to maintain a tool&#39;s tension accuracy to ensure bands are tensioned as expected. Accordingly, calibration devices are normally employed that selectively interconnect to a band tensioning tool to verify the functionality of the same. One drawback of traditional calibration devices is that they are usually complex, require precision parts, are difficult to calibrate themselves, and require considerable operator skill to ensure accurate readings. This last drawback is often due to a lack of visual feedback provided by the calibration tool. 
         [0059]    Accordingly,  FIGS. 19-23  show a calibration device  400  of one embodiment of the present invention used to calibrate the band tensioning tools described herein. The calibration device  400  includes a gauge body  404  that terminates in a hook  408 . The gauge body  404  also includes a slot  412 . In operation, the hook  408  is engaged onto a portion of the tool head (see  FIG. 21 ). The slot  412  accepts a portion of the tool&#39;s cutter arm which helps properly align the calibration device  400  in the proper location. The calibration device  400  may be further secured to the tool head with a magnet  416 . 
         [0060]    The calibration device  400  further includes a distal end  420  that secures a plate  424  with slotted holes (not shown). The plate  424  is interconnected to the distal end by at least one screw  428 . The plate  424  includes an aperture  432 , which will be described in further detail below. Finally, the calibration tool may include a stop  436  located on a stationary arm  440  that spans from the gauge body  404  and the distal end  420 . Finally, the calibration device  400  includes a movable arm  444  associated with the gauge body  404  at the calibration tool&#39;s proximal end  448 . The stop  436  prevents the arm  440  from moving past a predetermined point. 
         [0061]    Some embodiments of the present invention include an adjustment screw  452  that selectively engages an end  456  of the arm  444 , whereby the initial location of the movable arm end  456  is set such that the movable arm is pre-loaded towards the stop  436 . The movable arm  444  includes an opening  460  that cooperates with the aperture  432  in the plate  424 , which will be described in further detail below 
         [0062]      FIGS. 21-23  illustrate how the calibration device  400  of one embodiment of the present invention is used to calibrate a band tensioning tool  300 . As one of ordinary skill the art will appreciate, to accurately calibrate the tension band tensioning tool, the calibration device  400  must first be calibrated. Referring to  FIG. 21 , calibration device is done by inserting a band  464  through a forward opening  468  in the movable arm  444 , wherein the band head  446  is abutted against the movable arm  444 . The band  464  is also inserted through a rear opening  472 . A predetermined tension is added to the band in the direction of arrow C, which incrementally moves the movable arm end  456  and the movable arm  444  towards the stop  436 . The tension applied to the band  464  will move the arm end  456  a predetermined amount. Thereafter, the screws in the plate (  428  of  FIG. 19 ) are loosened and the plate  424  is moved along arrow D or E ( FIG. 19 ) to align the aperture  432  and the arm end opening  460 . Subsequently, whenever a band positioned within the calibration tool and tensioned with the band tensioning tool to that degree, the aperture  423  and the arm end opening  460  will be aligned. 
         [0063]    In operation, the gauge body  404  is first hooked on to an upper portion of the blade housing  370 . This aligns the rear opening  472  and the forward opening  468  of the calibration device  400  with the opening provided by the blade housing  470  that receives the free end of the band. Hooking the gauge body  404  onto the blade housing  370  also positions an inner surface  478  of the gauge body  404  in such a way to prevent movement of the cutter link  382 , which prevents movement of the knife  328 . The slot  412  receives the cutter arms  360  to position the calibration device laterally with respect to the primary axis of the band tensioning tool  300 . Finally, the magnet  416  provided by the calibration device will firmly secure it to the blade housing  370 . 
         [0064]    After the calibration device is secured to the band tensioning tool, a band  464  is placed through the forward opening  468 , the rear opening  472 , and through the channel  372  provided by the blade housing  370 . After the band  464  passes through the channel  372  it engages the gripper members as described above. Cycling of a tension handle  312  towards the handle  308  tensions the band  464  and moves the movable arm  444  towards the stop  436 . When a predetermined tension is achieved, (i.e., the tension the calibration device was tested to—the calibration tension), as indicated by the band tensioning tool, the operator assesses the aperture  432  positioned in the plate and the arm opening  460 . If the aperture  432  and the opening  460  are aligned, the tension provided by the tool equals the calibration tension. If the aperture  432  and the opening  460  do not coincide, the applied tension is incorrect and the band tensioning tool must be repaired. 
         [0065]    Alternatively, tension may be applied until the aperture  432  and the opening  460  are aligned and a tension reading is obtained from the tool. If the tension reading does not correspond with the calibration tension, the band tensioning tool must be adjusted. 
         [0066]    This method of assessing band tension is ideal as light passing through the aligned openings will indicate a predetermined tension has been achieved. That is, when the apertures  432  and the opening  460  are in line, light will shine through the calibration tool. One of ordinary skill in the art will appreciate the light coming through pin holes and solid bodies are very detectable by the human eye. Prior art tools rely on the ability of the operator to find markings, which is which may be fraught with errors. 
         [0067]    While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. It is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. Further, it is to be understood that the invention(s) described herein is not limited in its application to the details of construction and the arrangement of components set forth in the preceding description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.