Abstract:
An improved system and method for material bending comprises first handle  51 , second handle  61 , pivot rod  70 , roller  80 , and brace  82.

Description:
BACKGROUND AND SUMMARY 
     The present invention relates generally to devices for bending materials and specifically to sheet metal benders. Sheet metal brakes (“brake” or “brakes” herein) are known in the art. A typical brake system is of the type manufactured by “TAPCO” (trademark), such as model “Pro  14 ” as depicted in  FIG. 4 . Normal operation thereof comprises a user inserting sheet metal (not shown) in between locking anvil  5  and base hinge  6 . The user pulls handle  1  towards him or her which rotates cam shaft  3  which engages pivot arms  4  which push locking anvil  5  downward thereby clamping the sheet metal in place. 
     Next, the user grasps lifting handle  8  and thereby rotates moving hinge  7  and bends the sheet metal. After bending, lifting handle  8  is released. Next, the user releases handle  1 , which releases the sheet metal. The user can then reposition the sheet metal and repeat the above procedure to attain desired bending pattern in the material. Typical brake systems as described are problematic because they require two hands to operate. One hand must be dedicated to the operation of handle  1 . This slows the process. 
     An improved system is presented that overcomes this problem. The present invention is advantageous because one of the user&#39;s hands are freed. The function of locking and unlocking the sheet metal with handle  1  is accomplished with the user&#39;s foot. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a perspective view of the invention. 
         FIG. 2  depicts a side view of the invention. 
         FIG. 3  depicts roller  80   
         FIG. 4  depicts a perspective view of the prior art. 
     
    
    
     REFERENCE NUMERALS IN DRAWINGS 
     The table below lists the reference numerals employed in the figures, and identifies the element designated by each numeral.
           1  Handle Assembly of conventional brake  1       2  C-Casting  2       3  Cam Shaft  3       4  Pivot Arms  4       5  Locking Anvil  5       6  Base Hinge  6       7  Moving Hinge  7       8  Lifting Handle  8       9  Back Rail  9       40  Handle Assembly  40       51  First Handle  51       52  first end  52  of first handle     53  second end  53  of first handle     61  Second Handle  61       62  first end  62  of second handle     63  second end  63  of second handle     70  Pivot Rod  70       71  Upper end  71  of pivot rod     72  Lower end  72  of pivot rod     80  Roller  80       81  Foot Plate  81       82  Brace  82       83  upper end  83  of brace     84  lower end  84  of brace       

     DETAILED DESCRIPTION 
     Handle  1  of a conventional brake is replaced by handle assembly  40  ( FIGS. 1 ,  2 ) which is comprised of two handles, first handle  51  and second handle  61 . The handle assembly  40  forms a cantilever having the shape depicted in  FIG. 1 ,  2 ; It is to be understood that the definition of cantilever, in addition to dictionary meaning and definitions used in the art, includes the shape of handle assembly  40  as depicted. 
     Pivot rod  70  has upper and lower ends,  71  &amp;  72 , respectively. First ends  52 ,  62  of first and second handles  51 ,  61  fixedly engage the cam shaft  3  of a brake. Second ends  53 ,  63  of first and second handles  51 ,  61  slidingly engage upper end  71  of pivot rod  70  through roller  80 . 
     Generally, a roller is supplied operable to engage pivot rod  70  so as to transverse it longitudinally as pivot rod  70  rotates about brace  82 . Thus, force is transferred from lower end  72  of pivot rod  70  to handle assembly  40 . It is preferred that roller  80  be constrained laterally with respect to pivot rod  70  as it rolls. This can be accomplished by a roller with flanges, or a channel formed within the rolling surface of the roller. A preferred embodiment comprises a roller  80  ( FIG. 3 ) having lateral flanges to constrain pivot rod  70 . Roller  80  rotatedly engages second ends  53 ,  63  of first and second handles  51 ,  61 . 
     Pivot rod  70  is pivotably engaged to brace  82  at point operable to maximize the freedom of movement of pivot rod  70 . This can be accomplished in various ways. A preferred embodiment comprises pivot rod  70  bolted to brace  82  so as to allow rotation of upper end  71  of pivot rod with respect to brace  82 . Other ways to accomplish this include clevis pins and cotter pins and other methods known in the art. 
     Upper end  83  of brace  82  is fixedly secured to the back rail  9  of a brake. Brace  82  is positioned vertically below back rail  9  so as to engage pivot rod  70 . Preferably, foot plate  81  is fixedly secured to lower end  72  of pivot rod  70 . A preferred embodiment (FIGS.  1 , 2 ) comprises pivot rod  70  being straight. However, foot plate  81  is not necessary. The user&#39;s foot can engage lower end  72  of pivot rod in stead of roller  80 . 
     Another preferred embodiment (not shown) comprises pivot rod  70  being bent so as to place foot plate  81  closer to the user&#39;s foot. This provides for ease of use and greater application of force to pivot rod  70 . 
     As depicted in the figures, the shape and dimensions of handle assembly  40  are relative to the size of the brake being retrofitted. Therefore, the actual dimensions and shape will be apparent to those in the art. 
     As depicted in  FIG. 2 , a preferred embodiment comprises roller  80  being to the right of (or behind) c-casting  2 . Handle assembly  40  engages cam shaft  3  analogous to the way handle  1  engages cam shaft  3  in the traditional configuration depicted in  FIG. 4 . 
     In operation, the user depresses foot plate  81 . This causes pivot rod  70  to rotate about brace  82 . Pivot rod  70  engages roller  80  which in turn causes handle assembly  40  to rotate cam shaft  3 . Thus, handle assembly  40  causes cam shaft  3  to rotate as roller  80  travels longitudinally along pivot rod  70 . Otherwise, the bending operation is the same as the traditional method.