Abstract:
A safe circular horse pen which is easily assembled and disassembled. The pen is constructed of multiple panels arranged end-to-end. Each panel includes a vertical pole with an L-shaped leg and six horizontal bars secured to the vertical pole at vertically spaced apart intervals. The unattached ends of the poles are hollow and each unattached end couples to the next adjacent panel by receiving a loop extending from the side of the pole of the next adjacent panel such that a bolt may be passed through a vertical opening in the unattached end to lock each horizontal arm to the pole of the next adjacent panel. The individual panels may be nested in pairs for storage and shipping.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority under 35 USC §119 to provisional application 61/350,194 filed Jun. 1, 2010, which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    This invention pertains to circular or curved enclosing horse pens. 
         [0003]    Pens and fences have been used to corral livestock for centuries. In modern times, circular pens have been constructed of a series of fence panels having vertical posts on each end which are interconnected by fixed horizontal bars. The panels are connected end-to-end with chains or wire to form the pen. Such construction necessarily creates a pair of adjacent vertical posts at each panel connection and therefore provides a potential slot between the posts into which a hoof may become caught. The use of fence panels requires multiple chains or wire to make each end-to-end connection and involves considerable labor in set up and take down. 
         [0004]    In U.S. Pat. No. 6,840,194, a round pen is constructed of a series of vertical posts having openings for solid horizontal bars between adjacent posts and loops along the length of the posts to receive flexible cables which extend around all vertical posts of the pen. The pen of U.S. Pat. No. 6,840,194 is substantially permanent in that the vertical posts must be inserted into the ground to hold them upright during assembly of the pen. 
         [0005]    An easy to assemble curved pen which reduces risks of injury to penned horses is needed. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention provides a circular or round pen for horses which features a series of interconnecting panels which each have a single vertical pole with permanently attached horizontal bars extending from the pole. Each pole includes multiple loops or tabs along the pole, each loop or tab having an opening therethrough. Each loop or tab extends a short distance from the pole on the opposite side of the pole from the horizontal bars and is aligned with one of the horizontal bars. 
         [0007]    The free end of each horizontal bar includes a cavity into which the loop or tab of the vertical pole of an adjacent panel is inserted. A locking pin or bolt is passed through a vertical opening in the horizontal bar above and below the opening of the loop or tab, thereby connecting each horizontal bar to the vertical pole of the next adjacent panel. The construction results in a single vertical pole at the connections of adjacent panels so that no entrapments for animal hooves are present in the completed pen. 
         [0008]    The free ends of the horizontal bars are shaped to conform to the circumference of the pole members so that the loop inserted into each cavity is surrounded by the horizontal bar and hidden within it. Optionally, horizontal slots may be cut in opposing sides of the free ends of the horizontal bars alongside the receiving cavities to allow for additional variability in the angle made between a first panel and a panel adjacent to it. 
         [0009]    It is a primary objective of this invention to provide a lightweight circular pen that is strong, sturdy, easy to move and easy to assemble. It is a further objective of the invention to provide a circular pen which is free of gaps into which horses may become entrapped. It is still a further objective of the invention to provide a round pen that has hidden connectors between panels. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a perspective view of the preferred embodiment curved pen in a circular configuration. 
           [0011]      FIG. 2  is a perspective view of the pen of  FIG. 1  with the gate panel open. 
           [0012]      FIG. 3  is a perspective view of the standard pen panel of the invention. 
           [0013]      FIG. 4  is a close up exploded top view of the vertical post end of the panel of  FIG. 3  and an adjoining panel ready to be coupled to the vertical post. 
           [0014]      FIG. 5  is an enlarged perspective of the interconnection of a top horizontal bar of an adjoining panel to the vertical pole of a first panel. 
           [0015]      FIG. 6  is a perspective view of the gate panel seen in  FIGS. 1 and 2  linked to an upright hinge pole. 
           [0016]      FIG. 7  illustrates a nesting of first and second standard pen panels for shipment. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Throughout this specification, identical parts of the structure are referenced identically except multiples of the same element have been sometimes referenced by the indicator ′ beside the reference numeral. 
         [0018]      FIG. 1  illustrates a circular pen  2  according to the present invention with no openings in the pen  2 , the pen panels  10  creating an endless loop in cooperation with gate panel assembly  18  which includes gate panel  12 . Panels  10  and  12  are of generally equal height, preferably about six feet, to make the pen  2  suitable for horses. Panels  10 ,  12  are also of generally the same eight foot length, allowing twenty panels to make about a fifty foot diameter circular pen  2 . It can be seen that legs  16 ,  17  of panels  10 ,  12 , are generally L-shaped and rest on the ground surface  3 . 
         [0019]      FIG. 2  discloses the pen  2  with gate panel  12  open, that is with gate panel  12  rotated about hinge pole  80  and separated from formerly adjacent panel  10 ′. Panel  10 ′ is identical to each other panel  10  but has been denominated  16  to distinguish it from other panels  10  which are not adjacent to gate panel  12  when gate panel  12  is moved to the closed position. 
         [0020]    Referring now to  FIG. 3 , a standard panel  10  is illustrated and can be seen to comprise an upstanding post or pole  20  having leg  16  joined thereto at its lower end  22 . Vertical pole  20  is topped by cap  26 . Leg  16  is preferably integral with pole  20  and is curved to an L-shaped configuration such that lateral  24  of leg  16  is perpendicular to the longitudinal axis of pole  20 . Pole  20  and leg  16  are preferably formed of hollow  16  gauge galvanized pipe of approximately 1.75 inch diameter. 
         [0021]    Joined securely to vertical pole  20 , preferably by welding, are six horizontal bars  30  which join vertical pole  20  at first ends  32  thereof and extend in a first direction from pole  20 . Each horizontal bar  30  terminates in free end  34  which opposes first end  32  thereof. It can be observed that each horizontal bar  30  is hollow at free end  34 . Preferably each horizontal bar  30  is constructed of galvanized  16  gauge pipe of 1.75 inch diameter. 
         [0022]    Aligned with the longitudinal axis of each horizontal bar  30  is a retaining element  40  fixed to vertical pole  20  and extending a short length therefrom, preferably about one to two inches. Retaining elements  40  are horizontally aligned with the centerline of the horizontal bars  30  but extend in a substantially opposing direction. 
         [0023]    Generally, the effective height of pole  20  is six feet and each horizontal bar  30  is spaced along vertical pole  20  at one foot intervals. The nominal length of panel  10  is eight feet. 
         [0024]    Referring now additionally to  FIGS. 4 and 5 , details of the invention may be better observed.  FIG. 4  shows an enlargement of a segment of panel  10  wherein it can be seen that each horizontal bar  30  is welded to vertical pole  20  by a coping or saddle  36 , the end  32  of horizontal bar  30  being cut away to conform to the curved sidewall of vertical pipe  20 . 
         [0025]    Extending from vertical pole  20  opposingly to horizontal bar  30  is retaining element  40  which is welded or otherwise fixed securely to vertical pole  20 . Retaining element  40  preferably comprises a generally U-shaped loop  42  defining an opening  44  which is wider at the distal end  46  of loop  42  than at its proximal end  48 . Opening  44  is enlarged near distal end  46  to allow some variation in the location of a locking pin or bolt passing through opening  44 . 
         [0026]    The centerline  50  of retaining element  40  is at angle a from an extension of the longitudinal axis  52  of horizontal bar  30 . Angle a is preferably 10-25° and more preferably about 18°. Therefore the centerline  50  of each retaining element  40  is approximately 150 to 170 degrees separated from the direction of extension of each horizontal bar  30  from vertical pole  20 , that is, retaining elements  40  extend 150 to 170 degrees from the direction of the extension of horizontal bars  30  from vertical pole  20 . This orientation of retaining element  40  in relationship to the longitudinal axis  52  of horizontal bar  30  permits each panel  10  to join an immediately adjoining panel  10  to form a curved enclosure. When angle a is nominally 18°, a pen comprising 20 equal length panels  10  can be formed. However, with the variability of angle between one panel  10  and the next identical panel  10  provided by the outwardly tapered opening  44 , the panels  10  can be joined to provide differing diameters of pen  2 . Excess space in tapered opening  44  for bolt  64  allows the angle between neighboring panels  10  to vary from about 180 degrees to about 144 degrees. The width of tapered opening  44  at distal end  46  therefore allows one panel  10  to alternatively be longitudinally aligned with the adjacent panel  10  when a straight length of fence is desired. 
         [0027]      FIG. 4  also discloses horizontal bar  30  of an adjacent panel  10 . Free end  34  is hollow (each horizontal bar  30  may be a hollow pipe) creating a cavity  60  for receiving retaining element  40 . A vertical opening  62  transversely passes through horizontal bar  30  such that a bolt entering opening  62  will pass through opening  44  of loop  42  when retaining element  40  is substantially fully inserted into cavity  60 . 
         [0028]    In  FIG. 5 , the attachment of a first panel  10  to an adjoining panel  10 ′ is shown in an enlargement of the top of pole  20 . It is seen that horizontal bar  30  (the top most) is secured, preferably by welding, to vertical pole  20  including at saddle  36 . Adjoining panel  10 ′ is removably fastened to first panel  10  by the horizontal bars  36  thereof. The free end  34 ′ of horizontal bar  30 ′ is formed with a cope  38  which wraps around the vertical pole  20 . The uppermost retaining element  40  of pole  20  is not visible in  FIG. 5  because it has been inserted into the cavity  60  at free end  34 ′ of horizontal bar  30 ′. A bolt  64  having an enlarged head  66  which will not pass through opening  62  (see  FIG. 4 ) is in place, being locked in position by nut  68 . Cap  26  tops pole  20  while vent notch  28  is left open to the interior of pole  20 . 
         [0029]      FIGS. 4 and 5  make clear that variability in the angle between one panel  10  and the next can occur because the width of opening  44  of retaining element  40  is much larger than the diameter of a bolt  64  passing through it, thereby allowing differences in the diameter of pen  2 . 
         [0030]    It should be noted that slots may optionally be formed in free ends  34  to permit greater variability of angular relationship between adjacent panels  10 . 
         [0031]    Referring back to  FIG. 2 , it can be seen that gate panel  12  has been detached from first panel  10 ′ and swung outward around hinge pole  80  of gate assembly  81 .  FIG. 6  shows details of gate assembly  18 . 
         [0032]    Gate assembly  18  includes gate panel  12  and hinge pole  80 . Gate panel  12  is constructed very similarly to panels  10  except that a second pole  70  interconnects the distal ends  35  of horizontal bars  31  and is welded or otherwise permanently secured to horizontal bars  31 . Horizontal bars  31  are welded to first vertical pole  21  at approximately one foot spacings, beginning about one foot above the lateral segment  25  of leg  17 . Except for being part of first vertical pole  21 , leg  17  is identical to leg  16  of standard panel  10 . 
         [0033]    As can be seen in  FIG. 6 , first vertical pole  21  includes latch elements  71  which are in alignment with two of horizontal bars  31 . Latch elements  71  comprise upper and lower tabs  73 ,  75  which will align with two of the retaining elements  40  of a standard panel  10  such that latch pins  78  can be dropped through upper tab  73  through opening  44  of a retaining element  40  and then through lower tab  75  making a selectively latched connection with the pole  20  of an adjacent panel  10 . 
         [0034]    Second vertical pole  70  includes first hinge elements  72  which cooperate with complementary second hinge elements  82  of hinge pole  80 . Hinge pole  80  includes multiple retaining elements  40  which are identical to retaining elements  40  of standard panels  10 . The retaining elements  40  of hinge pole  80  couple to the free ends  34  of horizontal bars  30  of a standard panel  10  as illustrated in  FIG. 4  and described in reference thereto. As with retaining elements  40  of standard panels  10 , each retaining element  40  is located along hinge pole  80  so that it will align with the free end  34  of a horizontal bar  30  of the next adjoining panel  10 . Hinge pole  80  includes a leg  19  analogous to legs  16 ,  17 . Therefore, to provide a gate assembly  18 , a hinge pole  80  is attached to a standard panel  10 . Then a gate panel  12  is hinged to hinge pole  80  by aligning hinge panel elements  72 ,  82  and inserting hinge pins  84  therethrough. 
         [0035]      FIG. 7  shows two standard panels  10 ,  10  nested for shipment or storage. The first panel  10  may be laid on a pallet with horizontal bars  30  thereof extending toward a first side, namely the right-hand side as shown in  FIG. 7 , with the second panel  10 ′ laid beside and slightly offset from first panel  10  such that the horizontal bars  36  of second panel  10 ′ lie alongside but in opposite orientation to the horizontal bars  30  of first panel  10 . The free ends  34  of the horizontal bars  30  of first panel  10  will abut the vertical pole  20 ′ of the second panel  10 ′. Likewise, the free ends  34 ′ of horizontal bars  30 ′ of second panel  10 ′ will abut the vertical pole  20  of the first panel  10 . By nesting pairs of panels  10 , reduced space is needed to store or ship the pen  2  components. 
         [0036]    The foregoing description of the invention has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise form disclosed. Modifications and variations of the embodiments are possible in light of the above disclosure or such may be acquired through practice of the invention. The embodiments illustrated were chosen in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and by their equivalents.