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You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
     Anchoring objects to the ground is important for temporary structures such as tents. Ideally an anchor would require a lot of force to remove from the ground while it is working, yet be easily removed when desired. The anchor should also be small when not in use so it may be easily stored. Present solutions for having a great deal of holding power include auger type earth anchors that are difficult to install, quite large and usually heavy. There is a need for an anchor similar in size to a traditional tent stake, yet provides holding power comparable to an auger type anchor. 
     SUMMARY OF THE INVENTION 
     The present invention is a tie down anchor that is particularly useful when tying down objects to the ground and may take the place of ordinary tent stakes due to the tie down anchor&#39;s superior holding ability when compared to traditional tent stakes. The tie down anchor has a guide having an angled hole. A main stake extends downwardly from the guide and the main stake includes an aperture. A locking spike is adapted for being received in the angled hole. The aperture in the main stake is positioned to receive the locking stake when the locking stake passes through the angled hole. 
     The guide may include a stake aperture extending through the guide that is adapted for receiving the main stake. When used with a guide of this type, the main stake has a stop that locates the maximum depth the main stake may extend below the guide. The angled hole is adapted for guiding the locking spike through the aperture in the main stake when the stake extends to its maximum depth below the main stake. 
     In another aspect of the invention, the main stake may have a guide that is pivotally affixed to the main stake. The guide of this type has an angled hole adapted for receiving the locking stake. The guide is pivotal from a folded position adjacent to the main stake to another position in which the guide is substantially perpendicular to the main stake. A stop is included to limit movement of the guide to be substantially perpendicular to the main stake. 
     In yet another aspect of the invention, the main stake and guide are integrally joined and the main stake includes an angled hole adapted for guiding the locking spike through an aperture near the lower end of the main stake. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a tent stake of this invention; 
         FIG. 2  is a sectional view taken about the line  2 - 2  in  FIG. 1 ; 
         FIG. 3  is a perspective view of another embodiment of the tent stake fully assembled; 
         FIG. 4  is a perspective view of the tent stake shown in  FIG. 3  viewed from the opposite side as that of  FIG. 3 ; 
         FIG. 5  is a perspective view of the tent stake shown in  FIGS. 3-4  with its guides folded down; 
         FIG. 6  is an exploded perspective view of the tent stake shown in  FIGS. 3-5 ; 
         FIG. 7  is a sectional view taken about the line  7 - 7  in  FIG. 3 ; 
         FIG. 8  is a perspective view of another embodiment of the tent stake of the invention; and 
         FIG. 9  is sectional view taken about the line  9 - 9  in  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF INVENTION 
       FIG. 1  shows the ground anchor  10  of the present invention in an exploded view. The ground anchor  10  is particularly useful for anchoring tents or other objects to the ground  12 .  FIG. 2  shows a sectional view of the anchor  10  as used in the ground  12 . The anchor  10  has a guide  14 . The guide  14  has a stake aperture  18  adapted for receiving a main stake  20  and an angled hole  22  adapted for receiving a locking stake  24 . The angled hole  22  extends obliquely through the guide  14  and is angled toward the stake aperture  18  when traversing toward the ground  12  through the guide  14 . The stake aperture  18  has legs  25  and  26  that are straight slots through the entire thickness of the guide  14 . Leg  26  is shorter in length than leg  25 . The guide  14  may be made of a solid block of material, as shown in  FIGS. 1 and 2 , or can be made of tubular stock. When the guide  14  is made of solid stock, as shown in  FIGS. 1 and 2 , it is easier to insert the locking stake  24  and the main stake  20  into the guide  14  because there will be more bearing surface to guide each of the aforementioned parts through the guide  14 . However, in some instances it may be desirable to reduce weight by using a tubular construction as opposed to the solid construction shown in  FIGS. 1 and 2 . The main stake  20  has flanges  30 ,  31  that are perpendicular to each other. Standard angle stock may be used to manufacture the main stake  20 . One of the flanges  31  is shortened to leave a protrusion  34  near the top of the stake  20 . When the main stake  20  is made of standard angle stock having flanges of equal length, the short flange  31  is easily manufactured by removing stock from only one flange of the angle stock. A tie hole  35  is located in the protrusion  34  at the top of flange  31 ; however, this hole  34  could be located on the other flange  30 . The protrusion  34  prevents the main stake  20  from passing through the stake aperture  18 . The main stake  20  has a slot  38  near its lower end  40 . The lower end  40  is tapered to a point, as shown in  FIG. 1 , to enhance the main stake&#39;s  20  ability to penetrate the ground  12 .  FIG. 2  shows the ground anchor  10  as it is used in the ground  12 . The user of the ground anchor shown in  FIG. 2  will first place the guide  14  in a desired location on the ground  12 . The main stake  20  will then be inserted into the stake aperture  18 . The legs  25  and  26  of the stake aperture  18  will allow for only one possible way to install the stake  20  within the aperture  18 . As such, the slot  38  will face the angled hole  22 . With the main stake  20  in the stake aperture, the user will then pound the main stake  20  into the ground  12  until it stops due to the protrusion  34  engaging the guide  14 , as shown in  FIG. 2 . When the protrusion  34  engages the guide  14 , this will repeatably position the slot  38  in the same location below the guide  14 . This corresponds to the fully driven position because the main stake  20  cannot be driven any further. With the main stake  20  securely in the ground in its fully driven position, the locking stake  24  will be placed into the angled hole  22 . The angled hole  22  positions the locking stake  24  so it will intersect with the slot  38 . The user will then drive the locking stake  24  until it stops against the guide  14 . This is the fully driven position of the locking stake  24 . The slot  38  has a length chosen to allow for potential variation in the vertical location of the locking stake  24  relative to the guide  14 . This variation in vertical height of the locking stake  24 , particularly the lower end passing through slot  38 , may be the result of clearance in the angled hole  22 . This clearance may result from tolerance in the angled hole size  22 , variation in the outer diameter of the locking stake  24 , clearance between the main stake  20  and stake aperture  18 , or potential tolerance in the angularity of the angled hole relative to the guide. The slot  38  size in the main stake  20  is chosen so that, even with the maximum tolerances and necessary clearance between the locking stake  24  and angled hole  22 , the angled hole  22  will guide the locking stake  24  to intersect with the slot  38 . This intersecting relationship, as shown in  FIG. 2 , produces a secure anchor to the ground  12 . This intersecting relationship may also be had by using the stake aperture  18  in the place of the angled hole  22 , so it is the stake aperture  18  that is at an oblique angle relative to the guide  14  and the ground  12 , and the locking stake  24  would be perpendicular to the ground  12 . The force required to remove the anchor, as shown in  FIG. 2 , from the ground  12  will necessarily be much larger than that required to remove a single stake. Generally when removing a single piece stake, such as that in the prior art, the easiest way to remove the stake is to pull along the longitudinal axis of the stake. Also, in the case of the present invention, pulling directly upward on the main stake  20  is the easiest way to remove it from the ground. However, the main stake  20  will have the locking stake  24  interlocked within it so a force pulling upward on the main stake  20 , along its longitudinal axis, will not easily dislodge it from the ground  12 . The user may tie a rope through hole  35 . It is also contemplated that a tie hole  35  may be located on the guide  14 , itself. Removing the ground anchor  10  from the ground may be accomplished by first pulling the locking stake  24 , then the main stake  20 . 
     Guides  50  may also be attached to a main stake  52 , as shown in  FIG. 3 . In this case, each guide  50  is pivotally attached with a rivet  56  to the main stake  52  near its upper end. This pivotal attachment allows the guides  50  to be folded down along the main stake  52 , as shown in  FIG. 5 , and then unfolded, as shown in  FIGS. 3 and 4 . The limit to which the guides  50  may be folded upward is shown in  FIG. 4 . The guides  50  are prevented from pivoting upward when they reach the ninety degree position. Each guide  50  has a rivet  58  above it that catches each guide  50 , as shown in  FIG. 4 . Each guide  50  has an angled hole  60  extending through a flange  62 . The angled holes  60  are adapted for receiving a locking stake  64 . The angled holes  60  are set at slightly different angles with respect to their corresponding guides  50 . This is necessary because flanges  68  on the main stake have slots  70  staggered in their vertical position, as shown in  FIG. 3 . The upper slot  70 ′ has its lowermost portion above the uppermost portion of the lower slot. The different vertical heights of the slots  70 , on their respective flanges  68 , are necessary to prevent locking stakes  64  from hitting each other when driven through their corresponding angled holes  60 .  FIG. 3  shows how the locking stakes  64  pass near each other, but do not touch. The main stake  52  includes a tie hole  74  for receiving a rope. 
     A main stake  80  may also have an integral guide  82  extending from the main stake  80 . In this case, the guide  82  has an angled hole  84  to guide a locking stake  88  through a slot  90  near the lower end of the main stake  80 . Due to the fact that the main stake  80  and the guide  82  are integral, there is less overall variation in the final position of the locking stake  88  when it is fully driven into the angled hole  84 , as shown in  FIG. 9 . Thus, the slot  90  does not need to be as long as would otherwise be necessary if there were more tolerance between separate parts that would increase the variation in the final position of the locking stake  88 . Tie holes  92  are located in the top of the main stake  80  and on opposite sides of the main stake  80  in the guide  82 . 
     This invention is not limited to the details above, but may be modified within the scope of the following claims.

Summary:
A tie down anchor that is particularly useful when tying down objects to the ground and may take the place of ordinary tent stakes due to the tie down anchor&#39;s superior holding ability when compared to traditional tent stakes. The tie down anchor has a guide having an angled hole. A main stake extends downwardly from the guide and the main stake includes an aperture. A locking spike is adapted for being received in the angled hole. The aperture in the main stake is positioned to receive the locking stake when the locking stake passes through the angled hole. The stake of this invention is small, light, and of a comparable size to traditional tent stakes.