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FIELD OF THE INVENTION 
       [0001]    This invention relates to anchors. In particular, this invention relates to portable ground anchors for use in extracting vehicles from a trapped position by means of a winch. 
       BACKGROUND OF THE INVENTION 
       [0002]    Vehicles which travel off road, on unpaved surfaces or on weather covered streets are often subject to traps which prevent desired travel in the vehicles, These vehicles may encounter mud, snow, sand or other traps in which vehicle tires are deprived of significant friction against a solid surface. Without sufficient friction against a solid surface, vehicle tires are unable to provide adequate traction to propel the vehicle in motion and free it from the mire. A winch is a useful tool for freeing trapped vehicles from earthen traps. In order to free a trapped vehicle, a winch is situated between a nearby stationary object and the vehicle to be removed from the trap. One end of the winch is connected by cable, rope, chain or other line device to the nearby stationary object. The other end of the winch is either attached to the vehicle or connected to the vehicle by cable, rope, chain or other line device. Pulley action within the winch shortens the total length of line between the vehicle and the stationary object, and assists the trapped vehicle in freeing itself from the trap. 
         [0003]    A problem may arise for vehicles that become trapped in an area void of stationary objects such as trees, fenceposts, buildings, or other fixed structures. Without a stationary object, the line and winch has nothing to pull against, and the vehicle will remain trapped in the mire. 
         [0004]    Ground anchors are useful in freeing vehicles from the confines of snow, mud, sand or other traps when there are no stationary objects in the near vicinity to the trapped vehicles. Ground anchors provide the necessary ground gripping action to pull a vehicle from mire when there are no stationary objects in the nearby vicinity. 
         [0005]    Ground anchors of various types have been previously described as exemplified in U.S. Pat. Nos. 4,825,604 to Manning, 4,026,080 to Meikle and 3,500,589 to Ettinger. However, previous ground anchors have provided insufficient ground gripping when heavyduty vehicles must be removed from deep mire. Larger ground anchors are helpful in providing additional strength, but may be inconveniently bulky to haul and use. Additionally, many ground anchors are difficult to use or require substantial efforts to remove from the ground. 
         [0006]    Therefore, it is an object of the invention to provide a portable ground anchor of sufficient strength that heavy-duty loads may be applied to the anchor. Another object of the invention is to provide a portable ground anchor that is collapsible so that it may be easily hauled in a vehicle. It is a further object of the invention to provide a portable ground anchor that may be easily assembled, is convenient and simple to use, and requires little effort to remove from the ground and disassemble after use. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention relates to an improved ground anchor system for anchoring one end of a cable to the ground. The improved ground anchor system comprises a pair of hingedly attached, ground engaging base plates supporting a pair of vertically extending, pivoting central plates which are horizontally joined by one or more cable attachment bars. The base plates may be removably affixed to uneven or sloping ground by several long spikes or rods to provide a firm, but temporary and reusable anchor for a vehicle&#39;s winch cable. 
         [0008]    The ground anchor system is easily collapsed and stored in a vehicle so that it may be used upon demand. Furthermore, the ground anchor system is quickly and easily assembled for use and, upon assembly, provides sufficient strength that heavy loads may be supported by the anchor. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a side plan view of one embodiment of an improved ground anchor system in accordance with the present invention; 
           [0010]      FIG. 2  is a side plan view of the improved ground anchor system illustrated in  FIG. 1 , rotated about 90° from the viewing angle of  FIG. 1 , 
           [0011]      FIG. 3  is a top plan view of a first and a second base member of the improved ground anchor system taken substantially along line  3 - 3  in  FIG. 1 ; 
           [0012]      FIG. 4  is a side plan view of a central member of the improved ground anchor system illustrated in  FIG. 1 ; 
           [0013]      FIG. 5  is a plan view of a retention pin of the improved ground anchor system. 
           [0014]      FIG. 6A  is a side partial plan view of the first base member of the improved ground anchor system illustrated in  FIG. 1 . 
           [0015]      FIG. 6B  is an end view of the first base member taken substantially alone line  6 B- 6 B in  FIG. 6A . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0016]    Referring to  FIG. 1 ,  2  and  FIG. 3 , an improved ground anchor system  1  comprises a first base member  2 , a second base member  4 , a first central member  6 , a second central member  8 , spacers  10 , a hinge pin  12 , retainer clips  14 , and ground spikes  16 . 
         [0017]    The first base member  2  comprises a steel plate being about 10 inches wide, about 12 inches in length, and about 1 inch in thickness. Referring to  FIG. 3 , the first base member  2  includes a front portion  20 , a rear edge  22 , side edges  23  and  25 , first indented portion  26  adjacent side edge  23  of member  2 , second indented portion  28  adjacent side edge  25  of member  2 . A hinge member  24  extends outwardly from front portion  20 , and spike holes  30  extend at various locations through base member  2 . 
         [0018]    The second base member  4  also comprises a steel plate about 10 inches wide, about 12 inches in length, and about 1 inch in thickness. The second base member  4  comprises a front portion  32 , a rear edge  34 , side edges  33  and  35 , a first indented portion  38  adjacent side edge  33 , and a second indented portion  40  adjacent side edge  35 . A first hinge  42  and a second hinge  44  are formed on and extend outwardly from front portion  32 . A female slot  36  is formed between first and second hinges  32  and  34  to receive hinge member  24 . Spike holes  30  extend at various locations through base member  4 . 
         [0019]    With reference to  FIGS. 6A and 6B , hinge member  24  is formed by bending an extending portion of front portion  20  into a circle to form a circular channel  27  dimensioned to freely receive hinge pin  12 . Hinge members  42  and  44  are similarly formed by bending extending portions of front portion  32  into a circle to form a circular channel dimensioned to freely receive hinge pin  12 . The hinge member  24  is placed into female slot  36  so that the circular channel  27  of hinge member  24  aligns with the circular channels in hinge members  42  and  44 , and thus hinge pin  12  can be inserted through the channels so that first base member  2  and second base member  4  become pivotally connected. 
         [0020]    Ground spikes  16  are typically formed from cylindrical steel and are about 24 inches in length. The diameter of spikes  16  is slightly less that the diameter of spike holes  30  so that the spikes  16  can be inserted into holes  30  and pounded into the ground to secure the first base member  2  and the second base member  4  in a fixed position upon the ground. 
         [0021]    The hinge pin  12  comprises a steel shaft of about 12 inches in length and about ¾ inches in diameter. The hinge pin  12  further comprises small circular openings (not shown) drilled through hinge pin  12  at opposing ends and dimensioned to receive retainer clips  14 . The retainer clips  14  ( FIG. 5 ) may be inserted into the small circular openings in hinge pin  12  to prevent the hinge pin  12  from moving out of the circular channels in hinge members  24 ,  42 , and  44 . 
         [0022]    Referring to  FIGS. 1 ,  2  and  4 , central assembly  7  is pivotally joined to the assembly by hinge pin  12  extending through openings  50  at apexes  48  of central members  6  and  8 . The first central member  6  and second central member  8  each comprise a triangular shaped plate of steel  46  (see  FIG. 4 ), each having a width of about 5 inches at a base  51 , a height of about 8⅜ inches along edges  53  and  55 , and a thickness of about 1 inch. The first central member  6  and second central member  8  each further comprise a triangular apex  48 , a circular opening  50 , and spacer attachment openings  52 . The circular openings  50  of the first central member  6  and the second central member  8  are dimensioned slightly larger than hinge pin  12  so that hinge pin  12  can be freely inserted therethrough. Central assembly  7  is formed by placing the ends of spacers  10  into attachment openings  52  and retaining them by welding or other suitable means of attachment so that central members  6  and  8  are retained in a spaced apart relationship such that the apexes  48  will extend into indented portions  26 ,  28 ,  38  and  40  of base members  2  and  4 . Spacers  10  could also be threaded at each end and attached by using nuts on each side of members  6  and  8  to facilitate disassembly. The spacers  10  also provide a means to attach a winch cable  54  to the improved ground anchor  1 . Additionally, the spacers  10  permit the central assembly  7  to pivot around hinge pin  12 , and also add structural strength to the assembly. 
         [0023]    To assemble the combination, the first base member  2  and the second base member  4  are positioned so that the hinge member  24  is between hinges  42  and  44  in slot  36  so that the circular channels align. Central assembly  7  is positioned so that the openings  50  also align with the circular channels in the hinge members. Hinge pin  12  is inserted through openings  50  and the circular channels  27  and retainer clips  14  are placed through the openings in the hinge pin  12  to lock the hinge pin in place. The ground spikes  16  can be inserted into the spike holes  30  in first base member  2  and second base member  4  to position the spikes  16  to be driven into the ground. 
         [0024]    Operation of the improved ground anchor system  1  is now described. Once the assembly has been completed, the improved ground anchor system  1  is place at the desired ground location. Preferably, the base members should be oriented such that the hinge pin  12  is parallel to the bumper of the trapped vehicle and perpendicular to the force vector to be applied by the cable. Ground spikes  16  are pounded into the ground though the spike holes  30  to secure the first base member  2  and the second base member  4  to a fixed position against the earth. 
         [0025]    After anchoring the invention to the earth, the improved ground anchor system  1  may be used to free trapped vehicles from earthen mire, With the hinge pin  12  oriented approximately perpendicular to the cable  54  to be attached to the trapped vehicle, the central assembly  7  can be pivoted toward the trapped vehicle as shown by the dotted lines in  FIG. 1 . A winch (not shown) and cable  54  is used to link the trapped vehicle (not shown) to one or more of the spacers  10  of the improved ground anchor system. One end of a winch cable  54  is connected to the present invention  1  at a spacer  10 , and the other end of the winch and cable system is connected to the trapped vehicle. After the central assembly  7  is pivoted toward the trapped vehicle, the winch is operated to remove slack in the winch cable  54  and pull the cable taut. As the vehicle attempts to drive out of the mire, additional slack in the winch cable  54  is removed by operation of the winch until the vehicle is freed. By use of a winch and cable, the improved ground anchor system  1  is capable of assisting trapped vehicles and freeing them from mire. 
         [0026]    As may be seen, as force is applied to cable  54 , central assembly  7  pivots toward the mired vehicle thus bringing the line of force being applied along cable  54  closer to the plane of base members  2  and  4 . This increases the effectiveness of the anchor because the force applied is closer to the base members  2  and  4  making the force on the ground spikes  16  more in shear because the moment arm of the system is substantially reduced. Further, because base members  2  and  4  are pivotally connected at hinge pin  12 , the point at which the pulling force is applied to the assembly, any upward force on the pin  12  created by the moment arm of central assembly  7  tends to cause a downward force at the edge  22  of first base member  2  and edge  35  of second base member  4  thereby tending to cause the spikes  16  in first base member  2  to squeeze toward the spikes  16  in second base member  4  thereby tending to hold the spikes  16  more firmly in the ground. Thus, the present anchor is far more effective than if a single unitary base member were used. 
         [0027]    It will be appreciated by those skilled in the art that the present invention is capable of easy assembly and disassembly, and that upon disassembly, it may be conveniently carried in any vehicle. 
         [0028]    It will be further appreciated by those skilled in the art that the present invention may be fixed to the ground for other purposes such as to secure an airplane against the wind or a boat to the shore. Further the anchor of the present invention is useful for any purpose requiring a strong stationary ground anchor.

Summary:
A portable ground anchor system comprises base plate members having a hinge pin passage formed therethrough and each base plate member having a multiplicity of holes formed therethrough for interaction with ground spikes; central triangular shaped plate members having circular openings formed therethrough at a triangular apex thereof; a spacer member adapted to provide an engagement for a cable, said spacer member interconnected between said central triangular shaped plate members; a cylindrical pin for pivotally joining the base plate members and the central triangular members.