Abstract:
Disclosed herein are embodiments of a lead for a helical pile, comprising, a square shaft attached to the lead, the lead is provided with a base and a plurality of blades, and the blades extend axially from the base and are oriented with respect to one another so as to form more than two angles between each other.

Description:
FIELD 
       [0001]    Embodiments disclosed herein relate to leads and drives used in civil and utility guy anchors. 
       BACKGROUND 
       [0002]    It is known to use as a helical guy anchor with a helix that rotates about an axis; in such an application, square shaft and its helix act as a screw when the anchor is rotated into soil. In use, an initial guy anchor is rotated about its axis into the soil; after this initial guy anchor is installed, a subsequent anchor can be attached and the assembly is further rotated into the soil with additional anchors attached serially until the anchors collectively provide sufficient resistance for installation of guying cables. However, installers have encountered difficulty penetrating soil and hence advancing these helical anchors into the ground. 
         [0003]    One solution is to provide the initial anchor with a lead that helps break up tough soil and remove rocks and other impediments to installation. One such lead utilizes a fin that has been welded onto a square base. However, this arrangement has problems. Because the fin extends in one plane, tough soil and rocks must be moved 180°, thereby exposing the lead to greater torque and bending of the helix. Imperfections in welding process that attaches the fin to the base, as well as imperfections in the integrity of the fin itself, can cause the lead to weaken and eventually fail. Additionally, friction and compression with the soil can lead to heat build-up that also degrades the structural performance of the lead. 
         [0004]    Consequently, there exists a need for a lead that breaks up tough soil. There also exists a need for a lead that can withstand the forces inherent in pile installation. Additionally, there exists a need for a lead that breaks up soil, reduces the thrusting force necessary to penetrate soil, and hence reduces bending to the helix. Finally, there exists a need for a lead that dissipates heat more efficiently. Accordingly, the present invention is directed to overcoming the problems set forth above and other problems inherent in prior leads. 
       SUMMARY 
       [0005]    The scope of the present invention is defined solely by the appended claims, and is not affected to any degree by the statements within this summary. Disclosed herein are embodiments of a lead for a helical pile, comprising, a square shaft attached to the lead, the lead is provided with a base and a plurality of blades, and the blades extend axially from the base and are oriented with respect to one another so as to form more than two angles between each other. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a perspective view of a lead. 
           [0007]      FIG. 2  is a side view of the base and the blades included with the lead. 
           [0008]      FIG. 3  is a bottom view of the base and the blades. 
           [0009]      FIG. 4  is a perspective view of the bottom of the base. 
           [0010]      FIG. 5  is a top view of the base and the blades. 
           [0011]      FIG. 6  is a cross-sectional view of the blades. 
           [0012]      FIG. 7  is a bottom view of the base and the blades. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    The figures provided herein depict a preferred embodiment of the present invention. As shown in  FIG. 1 , a lead  10  is provided with an axis  11 , a base  50 , a tip  12 , a helix  40  and a plurality of blades  21 ,  22 ,  23 ,  24 , designated as a “first blade”  21 , a “second blade”  22 , a “third blade”  23  and a “fourth blade”  24 . The blades  21 ,  22 ,  23 ,  24  extend generally radially from the axis  11 , are each provided with a central plane  71 , and, as illustrated in  FIG. 5 , are oriented with respect to one another so that an angle  30  is formed between two blades as measured from each blade&#39;s central plane  71 . In the presently preferred embodiment, the blades  21 ,  22 ,  23 ,  24  are oriented so that the angle  30  between each blade measures 90 degrees. In an alternative embodiment, however, three blades are provided with the angle  30  between each of them measuring 120 degrees. In the foregoing embodiments, the angle  30  between each blade is equal in magnitude; however, in yet another alternative embodiment, the angle  30  between each blade becomes increasingly greater in the direction of rotation (counterclockwise when viewed from the tip  12 , as shown in  FIG. 5 .) 
         [0014]    Referring now to  FIG. 1 , wherein a perspective view of the lead  10  is shown, blades  21 ,  22 ,  23 ,  24  extend radially, so that each blade generally revolves about the axis  11  through the same volume (unless the lead  10  is advanced axially into the soil, in which case the blades revolve helically through different volumes). Though the presently preferred embodiment is provided with blades  21 ,  22 ,  23 ,  24  that are arranged radially, in an alternative embodiment, the blades are arranged helically about the axis  11 , and advantageously arranged along the same path as the helix  40 . In such an alternative arrangement, each blade revolves through a different volume. 
         [0015]    The blades  21 ,  22 ,  23 ,  24  are generally arranged radially about the axis  11 . In the presently preferred embodiment, the central plane  71  of each blade is offset from the axis  11  (which is shown in  FIG. 5  as extending out from the page). Within the foregoing generally radial arrangement, each blade is provided an offset  70  from the axis  11  of rotation. Each blade is preferably provided with the same offset  70  in the same direction (i.e. offset to the left or right of the axis  11 .) In the preferred embodiment, the offset  70  measures 0.1875 inches as measured from the axis to the central plane of each blade. One of skill in the art will appreciate that the foregoing dimension is scalable, and thus, the offset is roughly 5% of the largest diameter that the blades  21 ,  22 ,  23 ,  24  sweep through when the lead is rotated about the axis  11 . 
         [0016]    Each blade includes a plurality of sides located so as to face in opposing direction thereby providing each blade with a predetermined width  80 . As  FIG. 5  illustrates, each blade is provided with a first side  31  and a second side  32 . The sides of each blade are generally flat in the preferred embodiment; however, in an alternative embodiment, the sides  31 ,  32  are curved. Though each side  31 ,  32  is generally flat, each side is oriented so that the width of each blade decreases as the blade extends radially from the axis  11 . Thus, each blade is provided with a taper  81 . In the preferred embodiment, the taper  81  measures 10 degrees. 
         [0017]    Referring now to  FIG. 2 , the tip  12  is shown frusto-conically shaped, while in  FIG. 5 , the tip  12  is shown provided with a cone  13 , preferably a cone  13  that flares outwardly at an angle  113  of 120° as the tip extends to the base  50 . The blades extend from the tip  12  both in a generally radial and axial direction to an outwardly extending portion  25 . Illustrating the radial extent of the blades relative to the sides of the base  50 ,  FIG. 5  shows the base  50  provided with a plurality of corners  125 ,  122 ,  123 ,  124 , one of which is an exposed corner (a corner that is not located within the helix  40  but exposed to rocks or soil).  FIG. 1  shows the lead  10  provided with an exposed corner  125  after the helix  40  is welded onto the base  50 . Referring back to  FIGS. 2 and 3  illustrate, the outwardly extending portion  25  is curved and extends beyond the radial extent of the base  50 . As a result,  FIG. 7  shows the lead  10  provided with a blade radius  120  that is equal to or greater than the base radius  150 . Consequently, for at least the reason that the blade radius  120  is equal to or greater than the base radius  150 , the outwardly extending portion  25  is configured to push soil away from one of the corners  125 ,  122 ,  123 ,  124 , preferably the exposed corner  125 . 
         [0018]    As noted above, the helix  40  is welded to the base  50 , thereby creating an axial weld  145  extending axially up the sides of the base  50  where a curve  140  in the helix  40  meets the side of the base  50 , as shown in  FIG. 1 . The exposed corner  125  is configured to reduce bending and stress at the axial weld  145 . The exposed corner  125  pushes soil, rocks, and/or debris away from the curve  140  of the helix  40  (which is also the leading edge of the helix  40 ). For at least the reason that the outwardly extending portion  25  pushes soil away from the exposed corner  125 , and the exposed corner  125  pushes soil, rock, and/or debris away from the leading edge of the helix  40 , the outwardly extending portion  25  is configured to distribute the load placed on the leading edge of the helix  40 . 
         [0019]    The blades  21 ,  22 ,  23 ,  24  are integrally cast with the base  50 , which is shaped to cooperate with a shaft  60 , such as the shaft  60  of an augur  82 . The shape of the presently preferred embodiment is square; however, in alternative embodiments, the shape of the base  50  is out of round, such as a hexagonal shape. The base  50  is provided with a first base end  51  and a second base end  52 . The first base end  51  is shaped to cooperate with the augur  82 . In the case of the presently preferred embodiment, the first base end  51  is provided with a tapped hole  53  which secures the base  50  to the augur  82 . 
         [0020]    In the case of the preferred embodiment, the first base end  51  is provided with an inner portion  55  and a fastener-accepting extension  56  located therein. As a result of the hollowed portion  55 , the base  50  is divided into a plurality of internal walls  91 ,  92 ,  93 ,  94  (a first internal wall  91 , a second internal wall  92 , a third internal wall  93 , and a fourth internal wall  94 ) with a plurality of curved transitions  95 ,  96 ,  97 ,  98  (a first transition  95 , a second transition  96 , a third transition  97 , and a fourth transition  98 ) located therein between. As  FIG. 3  illustrates, the first transition  95  is located between the first internal wall  91  and the second internal wall  92 ; the second transition  96  is located between the second internal wall  92  and the third internal wall  93 ; the third transition  97  is located between the third internal wall  93  and the fourth internal wall  94 , and the fourth transition  98  is located between the fourth internal wall  94  and the first internal wall  91 . The transitions  95 ,  96 ,  97 ,  98  are curved in shaped, preferably radiused as each transition extends from one internal wall to another. As  FIG. 4  illustrates, the internal walls are provided with a predetermined thickness  99 . 
         [0021]    As  FIG. 2  illustrates, each of the blades  21 ,  22 ,  23 ,  24  also extends both radially and axially from the tip  12  and with each of the blades  21 ,  22 ,  23 ,  24  terminating at the second base end  52 . Thus, the edges of the blades impart a sloping profile to the lead  10 , as  FIG. 2  illustrates. As noted above, each of the blades  21 ,  22 ,  23 ,  24  decreases in width as each blade extends radially from the axis  11 . At the same time, the width  80  of each blade increases as each blade extends axially from the tip  12  to the second base end  52 . 
         [0022]    The second base end  52  is provided with a shaped surface  57 . Preferably, the second base end  52  is shaped to penetrate soil. In operation, the shaped surface  57  of the second base end encounters soil before the first base end  51 ; as a result, the shaped surface  57  extends axially away from the tip  12  towards the first base end  51 . Thus, as  FIG. 2  illustrates, the shaped surface  57  is oriented at an angle  31  relative to a plane orthogonal to the axis  11 . In one embodiment, the shaped surface  57  is frustoconically shaped; in another embodiment, the shaped surface  57  is shaped to form the sides of a pyramid; in yet another embodiment, the shaped surface  57  is provided with an ovoid or egg-like shape. In yet still another embodiment, the shaped surface  57  of the second end  52  is spherically shaped. Finally, in still another alternative embodiment, the shaped surface  57  is helically shaped (advantageously so as to match the helix  40 ). 
         [0023]    Referring now to  FIG. 4 , the base  50  is also provided with an outer base surface  58 . Because the internal walls  91 ,  92 ,  93 ,  94  and the transitions  95 ,  96 ,  97 ,  98  are provided with a uniform thickness  99 , the outer base surface  58  is generally shaped according to the inner portion  55  of the inner base  50 . The helix  40  is provided with an internal helical edge  41  which is shaped according to the outer base surface  58 . Because the internal helical edge  41  is shaped according to the outer base surface  58 , the helix  40  is welded to the base  50  where the internal helical edge  41  meets the outer base surface  58 . 
         [0024]    While this invention has been particularly shown and described with references to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.