Abstract:
A stably nestable tie down anchor comprising a pointed shaft with an auger blade at the pointed end and a U-shaped head at the other end with recesses formed in the end faces of the U-shaped head for receiving the shaft of an adjacently positioned anchor; said anchors being stably nestable by arranging a plurality thereof in head to toe relation with the shaft of each one adjacent the auger blade thereof received in one of the recesses in the head of the next adjacent anchor and vice versa and with the radially facing end faces of the heads of alternate anchors stably engaging each other and the auger blades of alternate anchors nested with each other; and a stable package of anchors formed by strapping together a group of nested anchors.

Description:
FIELD OF THE INVENTION 
     This invention relates to tie down anchors. More particularly, this invention relates to an irregularly shaped, stably nestable tie down anchor. Specifically, the present invention relates to a tie down anchor which can be stably packaged with a minimum of extraneous packaging material by nesting the anchors with each other and securing them together with a strap or the like. 
     BACKGROUND OF THE INVENTION 
     Tie down anchors are used to provide stable anchoring points for tying down house trailers, aircraft, large tents and similar objects or nonpermanent structures to prevent them from being moved from a desired location, and possibly damaged, by wind, etc. One end of the anchor is twisted into the earth and then a strap or cable connected to the object to be secured is fastened to the other end of the anchor. Typically, such anchors have irregular, unsymmetrical shapes. One preferred form of anchor which is highly effective and which can be economically manufactured comprises a shaft with a helical auger blade secured to one end and a head or mounting bracket at the other end to which a cable or strap may be fastened. 
     Packaging such irregularly shaped articles for transportion or storge poses problems. Heretofore, anchors of the described type have been mounted in sets in wooden frames for storage or shipment. Preparation of the frames and mounting of the anchors therein is time consuming and expensive. Moreover, the frames themselves add weight and take up space which increases shipping and storage costs. 
     Symmetrical articles such as pipes are often packaged by strapping them together in bundles (see U.S. Pat. No. 3,283,893). Attempts have also been made to bundle tie down anchors directly to each other in sets, but because of the irregular shape of each anchor, only loose bundles of the anchors have been produced. This approach has been found unsatisfactory because, with the individual anchors free to slide with respect to each other, the bundles are extremely awkward to handle. 
     It would be desirable if the anchors, despite their generally irregular shape, could be nested to form a stable unit. Heretofore, the only stably nestable anchors have taken the form of helical coils (see U.S. Pat. No. 2,559,732). 
     OBJECTS OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a tie down anchor which, despite its irregular shape, is stably nestable with other such anchors. 
     Another object of the present invention is to provide a tie down anchor which can be readily packaged as a stable unit. 
     A further object of the present invention is to provide a tie down anchor which can be packaged with a minimum of extraneous packaging material. 
     It is also an object of the present invention to provide a tie down anchor which can rapidly and efficiently be packaged at a low cost. 
     Yet another object of the invention is to provide a tie down anchor which when packaged is less expensive to transport or store. 
     A still further object of the present invention is to provide a package of stably nested tie down anchors. 
     SUMMARY OF THE INVENTION 
     These and other objects of the invention are achieved by providing a stably nestable tie down anchor comprising shaft means, auger blade means secured to said shaft means adjacent one end thereof and head means secured to the other end of said shaft means, and head means being provided with at least one recess for receiving the shaft means of a second tie down anchor and having at least one radially facing surface for stably engaging the head means of a third tie down anchor, said recess being formed in said radially facing surface of said head means. 
     The objects of the invention are further achieved by providing a package of tie down anchors comprising a plurality of individual tie down anchors each comprising shaft means, auger blade means secured to said shaft means adjacent one end thereof and head means secured to the other end of said shaft means, said anchors being assembled in interlocking, nesting relation alongside each other with the shaft means of each anchor adjacent the auger blade means thereof being received in a recess formed in the head means of an adjacent anchor, and said package further comprising strap means for holding said nested anchors in position with respect to each other. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be explained in further detail with reference to the accompanying drawings wherein: 
     FIG. 1 is a perspective view of a stably nestable tie down anchor according to the present invention; 
     FIG. 2 is a sectional view of the anchor of FIG. 1 taken along line 2--2 showing the bottom plan of the head means of the anchor; and 
     FIG. 3 is a plan view of a package of four stably nested anchors. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 is a perspective view of a preferred tie down anchor generally designated by reference numeral 1 comprising shaft means 2, auger blade means 3 and head means 7. Shaft 2 generally comprises a steel rod, the length and diameter of which will vary somewhat depending upon soil conditions. Generally rod diameters from about 1/2 inch to about 1 inch are useful. High tensile strength steels may be utilized. 
     Auger blade means 3 is formed from a circular steel plate having a central aperture corresponding to the diameter of the rod and a radial split extending from the aperture to the outer periphery of the plate. The split plate is twisted to a helical configuration, as shown, and welded to shaft 2. Desirably, the leading edge 4 and trailing edge 5 of auger blade means 3 are sharpened to facilitate movement of the auger blade through the earth as the anchor is twisted into, or out of, the ground. The end of shaft 2 adjacent auger blade means 3 is provided with a point 6 by cutting off the shaft at an angle with respect to the axis thereof. 
     Head means 7 comprises a U-shaped body 8 having a bottom portion 9 and projecting arms 10. A hole 11 is formed in bottom 9 of head means 7 which corresponds in diameter to shaft 2, and body 8 is secured to the shaft by inserting the shaft in the hole and welding the two pieces together. Of course, other types of heads, besides the described U-shaped head, could be utilized. 
     Two pairs of aligned apertures 12 are formed through the arms 10 of body 8 adapted to receive mounting bolts 13 for tie down cables or straps. If desired, polygonal depressions 14 corresponding in shape to the polygonal heads of bolts 13 may be formed in the outer wall of arm 10 around each aperture 12. Typically the mounting bolt heads 13 and the depressions 14 will be hexagonal in shape, as shown, but other configurations could be utilized as well. When the bolts are slightly loose, they can be turned to apply tension to the tie down strap or cable. When the desired tension on the cable or strap has been achieved, the bolt is held in place while the nut is tightened. Tightening the nut draws the head of the bolt into the depression until it is firmly engaged by the mating depression, thereby preventing rotation of the bolt and maintaining tension on the cable or strap. 
     In the illustrated embodiment, head 7 is eccentrically positioned with respect to shaft 2 so that one of the pairs of apertures 12 is aligned with shaft 2. This arrangement makes it possible, if desired, to use only a single mounting bolt 13 to fasten a tie down strap or cable to the anchor without applying a torsional stress to the head of the anchor. Of course, it is possible to use anchor heads which are symmetrically positioned or which contain only a single pair of aligned apertures 12. 
     The ends of arms 10 and bottom 9 of body 8 define radially facing end faces 15 of head means 7, and in each end face, a recess 16 is formed. Each recess 16 is adapted to receive the shaft 2 of an adjacently disposed anchor when a plurality of the anchors are nested as described hereinafter. The recesses may be more clearly seen from FIG. 2. 
     FIG. 3 shows a stable package 17 of four nested tie down anchors designated respectively by reference numerals 21, 41, 61 and 81, each of which corresponds in form to anchor 1 of FIGS. 1 and 2. Anchor 21 comprises shaft 22, auger blade means 23 and head means 27. Anchor 21 is placed alongside anchor 41 in head to toe relation therewith so that anchor shafts 22 and 42 are generally parallel. Shaft 42 of anchor 41 adjacent the auger blade means 43 thereof is received in the recess in one of the end faces of head means 27 of anchor 21, and shaft 22 of anchor 21 adjacent auger blade 23 thereof is received in the corresponding recess in one of the end faces of head means 47 of anchor 41. 
     A third anchor 61 is placed alongside anchor 41 in head to toe relation therewith on the opposite side from anchor 21. Anchor 61 is thus oriented similarly to anchor 21. Shaft 62 of anchor 61 is received in the recess in the other radially facing end face of head means 47 of anchor 41. Auger blade means 63 of anchor 61 nests with the auger blade means 23 of anchor 21, and one end face of head means 67 of anchor 61 is aligned with and engages the adjacent end face of head means 27 of anchor 21. The recesses in the engaging end faces of head means 27 and head means 67 mate to form a circular opening through which shaft 42 of anchor 41 passes. Desirably, the depth of each of the recesses is substantially the same as the radius of the shaft received therein so that shaft 42 is firmly clamped between head means 27 and 67. 
     A fourth anchor 81, comprising shaft 82, auger blade means 83 and head means 87, is placed alongside anchor 61 in head to toe relation therewith with shaft 82 generally parallel the shafts of the other anchors. Anchor 81 is thus oriented similarly to anchor 41. Shaft 82 adjacent auger blade means 83 is received in the recess in the other end face of head means 67. Auger blade means 83 is nested with auger blade means 43; and one end face of head means 87 is aligned with and engages the adjacent end face of head means 47 of anchor 41. As in the case of the engaging end faces of head means 27 and 67, the recesses in the engaging end faces of head means 47 and 87 are aligned and mate to form a circular opening through which shaft 62 of anchor 61 passes. 
     The shaft of each anchor is therefore received in a recess in the end face of the head means of at least one adjacently positioned anchor, and the head means of each anchor likewise receives the shaft of an adjacent anchor. The end faces of the head means of alternate augers stably engage each other; and the auger blade means of alternate anchors are nested with each other. The length &#34;L&#34; of each head means 7 should be at least as great as the radius of each auger blade means in order to provide sufficient separation between the shafts of alternate augers to facilitate proper nesting of the auger blade means of the augers. 
     Securing means such as one or more bands or wires of metal or high tensile strength polymeric material are passed around the assembled anchors and fastened snugly to form a stable package. In the illustrated embodiment two straps 18 of high tensile strength polyester are shown passed around the shafts of the assembled anchors adjacent the heads of the anchors and secured by friction welding. Alternatively, the straps could be fastened directly around the heads of the anchors or a single strap could be drawn about the center of the shafts. Steel bands or wires or other known types of packaging materials could be utilized instead of the described polyester bands. When the securing means are drawn around the shafts of the assembled anchors and fastened tightly enough to place the shafts of the outermost anchors of the assembly under slight lateral tension, the end faces of the heads are urged strongly against each other and an especially stable packaged unit results. 
     Stable packages of two or more anchors may be produced. The packaging technique of the invention is equally suitable for sets containing either even or odd numbers of anchors. The nesting pattern may be continued for up to twelve or more anchors. Generally packages will contain from 2 to 8 anchors, most usually a set of four anchors, as this is the most frequenctly required set size. 
     The foregoing embodiments have been set forth solely to exemplify the invention, and are not intended to be limiting. Modifications of the disclosed embodiments within the scope and spirit of the invention may occur to persons skilled in the art. For example, instead of being semicircular, recesses 16 could be V-shaped or trapezoidal. The heads could take various shapes. Also, a plurality of single-flight auger blades or a single multi-flight blade could be secured to each shaft. Accordingly, the scope of the invention is to be limited solely by the scope of the appended claims.