Abstract:
An apparatus for limiting an animal&#39;s movement includes a housing having a throughbore for accepting a shaft of a stake where the housing contains a retractable tether. A substantially conical support disposes about the shaft and attaches thereto and wherein the substantially conical support retains the housing at a selected elevation on the shaft and wherein a retaining mechanism retains the housing on the shaft.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to a restraint for an animal. More particularly, the present invention relates to a retractable tie out for the animal.  
         [0002]     Tie outs are used to limit the movement of animals, such as domesticated animals including, but not limited to, dogs, horses and cows. A typical tie out includes a tether of a fixed length having one end secured to the animal and the other end secured to an anchor that retains the anchored end of the tether in a selected location. Attaching the tether to the anchor prevents the animal from running free and confines the animal to roam within a generally circular area defined by the length of the tether. A typical anchor includes a stake that is forced into the ground which can be repositioned or a post that is permanently positioned in the ground.  
         [0003]     A longer tether gives the restrained animal greater freedom of movement within a larger area than the area provided with a shorter tether. However, a longer tether has a tendency of becoming tangled in the terrain, such as a rock or a tree, which consequently decreases the freedom of movement of the animal and defeats the purpose of the longer tether. Also, the animal may tangle the tether around the anchor which may also limit freedom of movement of the animal. A longer tether, designed to provide the animal greater freedom to move, may cause a reduction in the freedom of movement of the animal if the tether becomes entangled in an obstacle.  
         [0004]     To reduce the likelihood of the tether becoming tangled in an obstacle, while still providing the freedom of movement of a longer tether, the tether may be attached to a retractable reel. The reel is biased such that the tether retracts into the reel as tension is removed from the tether. When the animal applies force upon the tether that overcomes the bias, the reel rotates to increase the length of the tether. When the animal moves toward the anchor, the biased reel retracts the tether onto the reel and thereby reduces the length of the tether. As the length of the tether becomes shorter, the likelihood of the tether becoming entangled in an obstacle is reduced.  
         [0005]     While retractable tethers reduce the likelihood of the tie out becoming entangled in the terrain, the tether still has the potential of becoming entangled around the stake. When the tether becomes entangled about the stake, the freedom of movement of the animal is unnecessarily restricted.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention includes an apparatus for limiting an animal&#39;s movement. The apparatus includes a housing having a throughbore for accepting a shaft of a stake where the housing contains a retractable tether. A substantially conical support disposes about the shaft and attaches thereto and wherein the substantially conical support retains the housing at a selected elevation on the shaft and wherein a retaining mechanism retains the housing on the shaft. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]      FIG. 1  is a perspective view of the retractable tie out of the present invention.  
         [0008]      FIG. 2  is a top view of a dog secured to the retractable tie out of the present invention.  
         [0009]      FIG. 3  is a partial exploded view of the retractable tie out of the present invention.  
         [0010]      FIG. 4  is a sectional view of the present invention along section line  4 - 4  in  FIG. 3 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0011]     A retractable tie out of the present invention is generally illustrated in  FIG. 1  at  10 . The retractable tie out  10  includes a stake  12  having a distal end  14  for forcing into a surface such as soil to secure the retractable tie out  10  in a selected position.  
         [0012]     Referring to  FIGS. 1 and 2 , a tether  22  includes a distal end  24  that attaches to an animal such as a dog  19 . The dog  19  is secured to the distal end  24  of the tether  22 , preferably by securing the distal end  24  of the tether  22  to a collar  21  positioned about a neck of the dog  19 . Besides being capable of tethering a dog  19 , the tie out  10  of the present invention can also tether other animals, such as but not limited to, a cow, a horse, a goat and a sheep.  
         [0013]     A stop  26  is positioned about the tether  22  proximate the distal end  24  where the stop  26  engages a front surface  36  of a port  32  in a housing  30  to prevent the distal end  24  from retracting into the housing  30 . The port  32  includes an aperture  34  through which the tether  22  extends and retracts to adjust a length of the tether  22 .  
         [0014]     The housing  30  has a substantially circular sidewall  38  defined by an upper half  40  and a lower half  42 . The housing  30  is rotatably attached to the stake  12  proximate a proximal end  16  where the housing  30  rotates about an axis  13  of the stake  12 . As the dog  19  moves, the housing  30  rotates about the axis  13  of the stake  12  such that the tether  22  remains free of the stake  12 .  
         [0015]     Referring to  FIGS. 2-4 , the tether  22  is secured to a reel  20  that is positioned about the stake  12  and within a cavity  44  defined by the upper and lower halves  42 ,  40 , respectively. The reel  20  rotates about the axis  13  of the stake  12  to uncoil and coil the tether  22  onto the reel  20  to adjust a length of the tether  22 . Configurations of the housing other than circular are within the scope of the present invention provided that the reel  20  is permitted to rotate within the housing  30 .  
         [0016]     Referring to  FIG. 2 , as the dog  19  exerts a force on the tether  22 , the tether  22  comes under tension and uncoils from the reel  20 . As the length of the tether  22  increases, the dog  19  has more area to freely move as indicated by perimeter  23 . However, when the dog  19  moves toward the stake  12 , tension lessens on the tether  22 , and a retracting mechanism applies a force upon the reel  20  to reverse the rotation of the reel  20  about the axis  13  of the stake  12 . As the reel  20  rotates in the reverse rotational direction, the tether  22  is wound about the reel  20  and the area where the dog  19  can move lessens as indicated by perimeter  25  which also lessens the likelihood of the tether  22  becoming entangled in the terrain.  
         [0017]     Referring to  FIGS. 3 and 4 , a preferred retracting mechanism includes a coil spring  50  positioned within the cavity  44  of the housing  30  where the coil spring  50  engages the reel  20 . As the dog  19  uncoils the tether  22  by applying tension to the tether  22 , the coil spring  40  constricts. As the dog  19  further uncoils the tether  22 , the coil spring  50  further constricts, requiring greater tension to overcome the bias of the coil spring  50 . When the dog  19  releases tension on the tether  22  by moving toward the stake  12 , the coil spring  50  overcomes the tension applied by the dog  19  on the tether  22 , and the coil spring  50  uncoils, thereby reversing the rotation of the reel  20  and rewinds the tether  22  onto the reel  20 . As the tether  22  rewinds onto the reel  20 , the length of the tether  22  decreases, and thereby reduces the likelihood of the tether  22  becoming tangled in the terrain.  
         [0018]     The housing  30  and the reel  20  are retained in a selected position on the stake  12  by slidably positioning the stake  12  through a through bore  36  that is substantially centrally located in the housing  30  and engages a bottom surface  39  of the housing  30  with a spacer  58  positioned about the stake  12 . While the spacer  52  is discussed, the spacer  52  is not necessary to practice the present invention.  
         [0019]     A support  52  is fixedly attached to the stake  12 , preferably with a weld, and supports the spacer  52  and the housing  30  in a selected elevated position on the stake  12 . The support  52  includes a substantially circular perimeter  56  and an upper surface  54  having a convex configuration. While the support  52  with a convex upper surface  56  is preferred, other configurations of the support  52  that allow gravity to slide the tether  22  off the support  52  are within the scope of the present invention including a conical configuration, a frusto-conical configuration and a pyramid. While a fixed attachment of the support  52  to the stake  12  is specifically discussed, other attachments of the support  52  to the stake  12  are within the scope of the present invention, including, but not limited to a threaded engagement and engaging the support with a shoulder on the stake.  
         [0020]     The housing  30  and the reel  20  are retained on the stake  12  with a nut  60  threadably engaging a threaded portion  15  of the stake  12  proximate the distal end  14 . The nut  60  threadably engaging the threaded portion  15  of the stake  12  along with the support  52  fixedly attached to the stake  12 , retains the reel  20  and the housing  30  at the selected elevation on the stake  12 . A washer  61  preferably is positioned between the housing  30  and the nut  60  to prevent the nut  60  from galling the housing  30 . While a threaded engagement for retaining the housing  30  and the reel  20  on the stake  12  is preferred, other retaining mechanisms are within the scope of the present invention including, but not limited to, a snap ring, a pin engaging a through bore in the stake and a frictional engagement of a cap on the distal end of the stake.  
         [0021]     Referring to  FIGS. 1 and 3 , the stake  12  includes a shaft portion  62  that is threadably attached to an anchor portion  64 . The retractable tie out  10  is compactly packaged and/or stored when the shaft portion  62  is detached from the anchor portion  64 . However a stake  12  of a unitary construction having a shaft section and an anchor section is within the scope of the present invention.  
         [0022]     An upper wing  68  and a lower wing  66  are fixedly attached to the anchor portion  64  where the upper and lower wings  68 ,  66 , respectively, are preferably forced into the ground  18 . The upper and lower wings  68 ,  66  are preferably positioned on the anchor portion  64  such that vertical planes that define the wings  68 ,  66  intersect at substantially right angles. While wings  68 ,  66  are shown positioned at substantially right angles, other configurations of the wings  68 ,  66  are within the scope of the present invention.  
         [0023]     The wings  68 ,  66  aid in preventing the anchor portion  64  from rotating in the ground  18  when the dog  19  applies tension to the tether  22  and thereby aid in retaining the stake  12  in the selected location. While a stake  12  with substantially perpendicular wings  66 ,  68  is preferred, a stake having one wing or no wings is also within the scope of the present invention.  
         [0024]     The tether  22  provides adequate flexibility for the dog  19  to freely move within the area. However, the tether  22  should include enough rigidity such that the tether  22  does not sharply bend and thereby prevent the dog  19  from tangling the tether  22  on obstacles on the ground  18 . Further, the tether  22  preferably has a diameter or thickness that positions within a gap  70  defined by the bottom surface  39  of the housing  30  and the upper surface  54  of the support  52 .  
         [0025]     When the tether  22  is positioned within the gap  70 , the downwardly sloped convex upper surface  54  allows gravitational force to slide the tether  22  off of the upper surface  54  of the support  52  and thereby prevents the tether  22  from becoming entangled between the housing  30  and the support  52 . If the dog  19  moves such that the tether  22  engages the stake  12  below the support  52 , the tether  22  engages the circular perimeter  56  of the support  52  that prevents the tether from becoming entangled with the stake  12 .  
         [0026]     The tether  22  preferably includes a metal cable having a plastic or polymeric coating. While a cable is specifically discussed, other types of tethers are within the scope of the present invention including, but not limited to, a chain, a rope and a strap.  
         [0027]     Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.