Abstract:
A wire bending device that includes a housing have a top plate, wherein the top plate includes a curved slot, a first pair of opposing wheels positioned over the top plate for feeding wire, and a bend head. The bend head includes an aperture configured to pass the wire fed from the first pair of opposing wheels, and first and second bend surfaces positioned adjacent to the curved slot and the aperture. A cam member that includes sloping cam surfaces, and a rotating pulley, both positioned under the top plate and configured to cause a first pin to rise up and travel along the curved slot for engaging with and bending wire against the first bend surface, and to cause a second pin to rise up and travel along the curved slot for engaging with and bending wire against the second bend surface.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 62/057,935, filed on Sep. 30, 2014 and PCT Patent Application No. US2015/053197 filed on Sep. 30, 2015, which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to devices that bend wire into desired shapes. 
       BACKGROUND OF THE INVENTION 
       [0003]    Wire benders are devices that bend wire into desired 2-dimensional or 3-dimensional shapes. Early wire benders provided a mechanism that allowed a user to manually bend wire into desired shapes. See for example U.S. Pat. Nos. 4,091,845 and 5,809,824. More recently, motorized wire benders have been developed that use a moving pin under motor control to bend wire, some even operating under computer control. See for example U.S. Pat. No. 5,088,310. Drawbacks of such devices, however, include excessive expense, complexity and size. Additionally, such devices are difficult to set up and operate for each desired wire shape. 
         [0004]    There is a need for a wire bender device design that is simple and relatively inexpensive and easy to operate, so that wire shapes can be effectively and efficiently created. 
       BRIEF SUMMARY OF THE INVENTION 
       [0005]    The aforementioned problems and needs are addressed by a wire bending device that includes a housing have a top plate, wherein the top plate includes a curved slot, a first pair of opposing wheels positioned over the top plate for feeding wire, and a bend head. The bend head includes an aperture configured to pass the wire fed from the first pair of opposing wheels, and first and second bend surfaces positioned adjacent to the curved slot and the aperture. A cam member is disposed below the top plate, wherein the cam member includes a first vertically sloping cam surface, and a second vertically sloping cam surface. A rotatable pulley is disposed between the cam member and the top plate, and includes first and second holes. A first pin has a first end slidably engaged with the first cam surface, a middle portion extending through the first hole, and a second end. A second pin has a first end slidably engaged with the second cam surface, a middle portion extending through the second hole, and a second end. A motor is configured to rotate the pulley in opposing first and second rotational directions. The pulley rotating in the first rotational direction causes the first pin first end to slide along the first cam surface so that the first pin second end rises vertically through the curved slot and then travels along the curved slot for engaging with and bending the wire passing through the aperture against the first bend surface. The pulley rotating in the second rotational direction causes the second pin first end to slide along the second cam surface so that second pin second end rises vertically through the curved slot and then travels along the curved slot for engaging with and bending the wire passing through the aperture against the second bend surface. 
         [0006]    Other objects and features of the present invention will become apparent by a review of the specification, claims and appended figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view of the wire bender. 
           [0008]      FIGS. 2A and 2B  are bottom views of the bend head. 
           [0009]      FIG. 3  is a perspective view of the wire bender. 
           [0010]      FIGS. 4A-D  are perspective view of the cam member with the pins in different positions. 
           [0011]      FIG. 4E  is a perspective view of the springs on the pins. 
           [0012]      FIGS. 5A and 5B  are perspective views of the timing pulley. 
           [0013]      FIG. 6  is a bottom perspective view showing the components underneath the top plate. 
           [0014]      FIG. 7  is a perspective view showing the motors of the present invention. 
           [0015]      FIG. 8  is a side view showing the timing belt engaged with the pulley. 
           [0016]      FIG. 9  is a perspective view showing the feed wheels  14   a.    
           [0017]      FIG. 10  is a bottom view showing the spring loaded bearing system. 
           [0018]      FIG. 11  is a top view of the spring loaded bearing system. 
           [0019]      FIG. 12  is a view of an interface screen. 
           [0020]      FIG. 13  is a view of a calibration screen. 
           [0021]      FIG. 14  is a view of a calibration screen. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]    The present invention is a desktop sized wire bender that converts drawn curves into bent wire having 2-dimensional or 3-dimensional shapes. The wire bender  1  is shown in  FIG. 1 , and includes a housing  10  having a top plate  12 . 
         [0023]    The top plate  12  serves as a work surface on which the wire manipulation components are positioned. These components include two pairs of feed wheels, with each pair including two wheels  14   a  and  14   b  that pinch and manipulate the wire fed therebetween. Wire guides  16  are aligned with the gap between the feed wheels  14   a  and  14   b,  and include apertures  18  through which the wire can be fed (to guide the wire in the proper direction). 
         [0024]    A bend head  20  is aligned with the wire guides  16 . The bend head  20  is better shown in  FIGS. 2A and 2B , and includes an aperture  22  through which the wire can be fed to hold the wire in place while it is being bent. Bend head  20  also includes a pair of bend surfaces  24   a  and  24   b,  one on each side of the aperture  22 . As shown, a wire  26  is fed through aperture  22 , and is bent around bend surface  24   a  by moving pin  28 . 
         [0025]    Pin  28  travels (translates) in an arch shape path, as best shown in  FIG. 3 , which is dictated by arch shaped slot  30  formed in plate  12 . Pin  28  protruding through slot  30 . 
         [0026]    Starting at a first end  30   a  of the slot  30 , the pin  28  travels along slot  30  until it engages and pushes on wire  26  (wrapping the wire around bend surface  24   a ) until the desired bend shape is achieved in the wire. At that point, pin  28  retreats partially or fully back to the first slot end  30   a,  whereby the wire is advanced to the next target location of the wire to be bent. To implement bends in the opposite direction, a second pin  32  begins at the second end  30   b  of the slot  30 , and travels along slot  30  until it engages and pushes on wire  26  (wrapping the wire around bend surface  24   b ) until the desired bend shape is achieved in the wire. At that point, pin  32  retreats partially or fully back to the second slot end  30   b.  Pins  28  and  32  are a fixed distance apart in slot  30 , and rotate together during operation. As pin  28  approaches the first end  30   a  of the slot, pin  28  retracts below the surface of top plate  12  so as to not interfere with the operation of second pin  32 . Likewise, as pin  32  approaches the second end  30   b  of the slot, pin  32  retracts below the surface of top plate  12  so as to not interfere with the operation of first pin  28 . 
         [0027]      FIGS. 4A-4D  illustrate a cam member  34  positioned underneath plate  12  that provides two annular tracks  36  and  38  for pins  28  and  32 , respectively, for controlling the vertical heights of pins  28  and  32  as they translate in their respective arc shaped paths. Track  36  includes a sloping cam surface. Track  38  includes a sloping cam surface in the form of a pair of rails that extend up from the edges of first track  36 . At position A, the tracks  36  and  38  are approximately equal in vertical position. Moving clockwise from position A toward position B, the cam surface of track  36  slopes vertically down, whereas rails of track  38  slope vertically up. Pin  28  terminates in a first flange  42  that engages with and slides along first track  36 . Pin  32  terminates in a second flange  44  larger than flange  42  that engages with and slides along second track  38 . Both pins  28  and  32  are spring biased downwardly by springs  40  so their respective flanges  42 ,  44  stay engaged with their respective tracks  36 ,  38 , as shown in  FIG. 4E . 
         [0028]    Pins  28  and  32  are spaced apart by a fixed distance, and translate in the arced path clockwise and counterclockwise together. As the pins move clockwise, pin  28  drops vertically as its flange  42  slides along the dropping track  36 , while pin  32  rises vertically as its flange  44  slides along rising track  38 . The opposite occurs as the pins move in the counterclockwise direction. Therefore, starting with the positioning in  FIG. 4A , pin  28  is in its extended position (i.e. it extends up through slot  30  of plate  12  for engaging with wire  26 ), and pin  32  is in its retracted position (i.e. positioned below plate  12  and not extending up through slot  30 ). As the pins travel in the clockwise direction (from  FIG. 4A  to  FIG. 4D ), pin  28  drops down to its retracted position to disengage from slot  30 , and pin  32  extends up to its extended position to extend up through slot  30  for engaging with wire  26 . As the pins travel in the counterclockwise direction (from  FIG. 4D  to  FIG. 4A ), pin  32  drops down to its retracted position to disengage from slot  30 , and pin  28  extends up to its extended position to extend up through slot  30  for engaging with wire  26 . With this configuration, only a single motor is needed to translate the pins clockwise or counterclockwise along the arced path, where tracks  36  and  38  dictate the vertical height of the pins so that each pin drops below top plate  12  for large bend angles so as to not interfere with the other pin&#39;s engagement with the wire  26 , and so that each pin rises up through slot  30  to engage with and bend the wire  26  as the other pin drops below plate  12  and out of the way for large bend angles in the opposite direction. Specifically, as pin  32  bends the wire  26  to the left (in  FIG. 3 ) at a large bend angle, pin  28  will drop below plate  12 , and as pin  28  bends the wire  26  to the right at a large bend angle, pin  32  drops below plate  12 . 
         [0029]      FIG. 5A and 5B  illustrate a timing pulley  46  for translating pins  28  and  32  in their arced path. Specifically, pins  28  and  32  extend through holes  48  in pulley  46 . Pulley  46  includes teeth  50  that engage with a timing belt  51 , which in turn engages timing pulley  52  that is rotated by bend motor  54 , as shown in  FIGS. 6-8 . Therefore, a single motor  54  drives both the translational and vertical movement of the pins  28 ,  32 . This configuration eliminates the need for an additional electromechanical or other means to lower and raise pins  28 ,  32  as they are translated. 
         [0030]    Also shown in  FIGS. 6 and 7  is feed motor  56  which drives feed wheels  14   a / 14   b . A drive belt is engaged with pulleys  58  of feed wheels  14   a  (see  FIG. 9 ) and pulley  60  of feed motor  56  (see  FIG. 7 ). Feed wheels  14   a / 14   b  operate synchronously because they are both driven by the same drive belt and feed motor  56 . Both motors  54 ,  56  mount to slots  64  of the same motor plate  62  to allow the belt tensions to be adjusted. As shown in  FIG. 9 , the feed wheels  14 A are swappable to accommodate different sizes of wire. Bend head  20  can also be swapped with one having a different size aperture to accommodate different wire sizes, and/or bend surfaces with different radii of curvature for different desired wire bend radii. Bend head  20  is preferably held in place by two screws and four pins to ensure stability as the wire is fed through. Varying bend head designs can be provided to accommodate fine wire to rod and tube, and to accommodate materials from strong steel to soft plastic. 
         [0031]    Referring back to  FIGS. 1 and 3 , the top plate  12  can include ramp protrusions  66  that push the bent wire  26  up and over the other components on top plate  12  and the fed wire itself (i.e., so that bent wire  26  does not interfere with the operation of any such components and/or is caught by such components that would unintentionally further bend the bent portion of the wire.) 
         [0032]    Feed wheels  14   b  are preferably mounted on a spring loaded plate  67  relative to feed wheels  14   a.  As shown in  FIGS. 10-11 , a spring-loaded bearing system  68  is used to supply a consistent force between opposing wheels  14   a  and  14   b.  A tension adjust bolt  70  can be used to adjust the amount of force. The spring-loaded bearings and changeable feed wheels  14   a  enables accommodation of a large variety of wire sizes. The bearing system  68  and feed wheels  14   a / 14   b  keep the wire centered to prevent jams. 
         [0033]    The wire bender  1  is preferably operated under the control of a microprocessor  72  located inside housing  10 . Alternately and/or additionally, an external computer or controller can be used to control the operation of the wire bender  1 . Software running on the microprocessor  72  and/or external computer or controller can provide the user the ability to control the wire bender  1  without complex coding or programming using a convenient user interface screen. An exemplary user interface screen  80  is illustrated in  FIG. 12 , we can be generated on a display connected to the wire bender  1 , or generated on a computer connected to the wire bender  1 . Screen  80  allows the user to create desired wire shapes, either drawn manually or created from user provided vector-based files such as .SVG or .DXF. Once the bend shape  82  is defined, bend points  84  are added (indicating where the wire will be bent to create shape  82 ). The resolution scale of the bend shape  82  can be adjusted. The bend points  84  can be moved, added or deleted by the user. The interface can indicate if any of the bend points are too close together or are at too sharp an angle. The interface can also allow the user to select the wire material, the units, the wire length, the scale and resolution of the displayed shape, a smart point mode in which straight line segments are automatically recognized and the bend points are evenly distributed across the curves, and a gap threshold under which the interface will automatically close any gaps. 
         [0034]    The interface includes a calibration screen  86  (see  FIG. 13 ) that compensates for springback, which is slight movement in the reverse direction by the wire after a bend is created. To implement the desired bend in most wires, the wire is slightly over-bent so that after springback, the wire is left with the desired amount of bend. Wires of different materials and/or diameters will exhibit different springback characteristics. The calibration screen allows the user to calibrate the amount of over-bending compensation for the given wire being used. After the user inputs the wire material, accuracy level (high accuracy takes longer and uses more wire), and bend head being used, the wire bender begins calibration. Calibration involves implementing a bend in the wire, and then having the user manually position the pin so that is just touches the wire (whereby the pin position indicates to the device the actual bend of the wire after springback). This is performed several times for both directions, as illustrated in  FIG. 14 . The column titled “Actual” will populate with the actual angles to which the wire has been bent as determined through calibration. Through this process, the wire bender  1  will determine an overbend correction factor which will dictate how much over-bend compensation will be used at the various angles given the actual wire being used and comparisons between attempted and actual wire bends performed by the calibration. Subsequent wire bending is then performed by overbending the wire based upon the overbend correction factor. 
         [0035]    It is to be understood that the present invention is not limited to the embodiment(s) described above and illustrated herein, but encompasses any and all variations falling within the scope of the appended claims. For example, references to the present invention herein are not intended to limit the scope of any claim or claim term, but instead merely make reference to one or more features that may be covered by one or more of the claims. Materials, processes and numerical examples described above are exemplary only, and should not be deemed to limit the claims. 
         [0036]    Hardware, software and/or firmware can be used to implement any of the logic steps and/or processes discussed above. It should further be appreciated that such logic steps or processes can be implemented as computer-executable instructions stored on a non-transitory computer readable medium, such a CD or DVD (including re-writable CDs and DVDs), flash or other non-volatile memory, ROM, EEPROM, disc drive, solid state drive, etc. When the program code is loaded into and executed by a machine, such as a computer or dedicated processer, the machine becomes an apparatus for practicing the invention. The present invention can also be embodied in the form of program code, for example, whether stored in a storage medium, loaded into and/or executed by a machine, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the program code is loaded into and executed by a machine, such as a computer or processor, the machine becomes an apparatus for practicing the invention. When implemented on a general-purpose processor, the program code segments combine with the processor to provide a unique device that operates analogously to specific logic circuits. 
         [0037]    It should be noted that, as used herein, the terms “over” and “on” both inclusively include “directly on” (no intermediate materials, elements or space disposed therebetween) and “indirectly on” (intermediate materials, elements or space disposed therebetween). Likewise, the term “adjacent” includes “directly adjacent” (no intermediate materials, elements or space disposed therebetween) and “indirectly adjacent” (intermediate materials, elements or space disposed there between), “mounted to” includes “directly mounted to” (no intermediate materials, elements or space disposed there between) and “indirectly mounted to” (intermediate materials, elements or spaced disposed there between), and “electrically coupled” includes “directly electrically coupled to” (no intermediate materials or elements there between that electrically connect the elements together) and “indirectly electrically coupled to” (intermediate materials or elements there between that electrically connect the elements together). For example, forming an element “over a substrate” can include forming the element directly on the substrate with no intermediate materials/elements therebetween, as well as forming the element indirectly on the substrate with one or more intermediate materials/elements therebetween.