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BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to molded plastic fences and, more specifically, to a molded plastic fence having both a front section and a rear section each having an inner side, wherein all molding artifacts, e.g. ribs, ejection pin marks, etc., are disposed on the front and rear fence section inner sides, and wherein the front and rear fence sections are joined together and enclose the inner sides whereby a visually sealed fence section is created. 
     2. Background Information 
     Plastic fences are used in many locations for decorative fences. Such decorative fences were originally assembled from wood. Wooden fences had the advantage of being generally uniform on both the front and back sides and were, therefore, visually pleasing. Wooden fences, however, were also expensive, heavy, and subject to degrading when exposed to weather. Plastic fences could be molded, generally, into the shape of wooden fences and were inexpensive, light, and weather resistant. Plastic fences, however, included molding artifacts, e.g. ribs, ejection pin marks, etc., which were visually unattractive. 
     Such molding artifacts were generally placed on the “back” side of the plastic fence in an attempt to keep the molding artifacts hidden from view. While molding artifacts on the rear side of a fence could not be seen from the front, such molding artifacts were still clearly visible when an observer moved to the side of the fence. In an attempt to further hide the molding artifacts, fence elements, e.g. posts, slats and rails, were molded as deep C-shaped channels wherein the molding artifacts were disposed at the bottom of the channel. This shape helped hide the molding artifacts from observers standing to the side of such fences. However, observers behind such deep channel fences, e.g. a person in a yard looking at such fences lining a sidewalk, could still see the molding artifacts in the deep channels. Further, the fact that the fence elements can be observed as not being solid further detracts from the fence&#39;s attractiveness. 
     SUMMARY OF THE INVENTION 
     The disadvantages of the prior art are overcome by the concept embodied in the claims set forth below. The concept provides for a molded plastic fence having a unitary front fence section and a unitary rear fence section which are coupled together to form a fence without visible internal molding artifacts. To emulate a traditional wooden fence, the fence sections preferably include various fence elements such as posts, slats and rails. The fence elements on each fence section typically have a planar member with an inner side and a raised edge extending from the inner side. The molding artifacts are disposed on the inner sides of the fence elements. The unitary front fence section and a unitary rear fence section are coupled with the raised edges engaging each other. In this configuration the interior molding artifacts are hidden from view and the fence elements appear as solid. Preferably, substantially all molding artifacts are disposed on the inner side of the fence sections and the external surface of the fence assembly are substantially free from molding artifacts. A fence in this configuration has the advantages of both a wooden fence and a plastic fence. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which: 
         FIG. 1  is a front view of an exploded fence assembly. 
         FIG. 2  is a cross-sectional view of a fence element wherein the fence sections are separated. 
         FIG. 3  is a cross-sectional view of a fence element wherein the fence sections coupled. 
         FIG. 4  is an isometric view of a fence element wherein the fence sections are separated. 
         FIG. 5  is a view of the inner side of a fence element showing part of a coupling device. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As used herein, “coupled” means a link between two or more elements, whether direct or indirect, so long as a link occurs. 
     As used herein, “directly coupled” means that two elements are directly in contact with each other. 
     As used herein, “fixedly coupled” or “fixed” means that two components are so coupled to move as one. 
     As used herein, the word “unitary” means a component is created as a single piece or unit. That is, a component that includes pieces that are created separately and then coupled together as a unit is not a “unitary” component or body. 
     As shown in  FIG. 1 , a molded plastic fence assembly  10  includes a number of fence elements  12 . As shown, the fence elements  12  include posts  14 , slats  16  and rails  18  that are generally vertical or horizontal elements that extend generally perpendicular to each other. It is understood that the fence elements  12  may have other shapes, such as, but not limited to, curved (not shown), and/or other orientations, such as, but not limited to, angled, as in a lattice (not shown). The posts  14  may include spikes  15  structured to be disposed in the ground and thereby hold the fence assembly  10  upright. As the spikes  15  are to be buried and not generally visible, the spikes are not fence elements. The fence assembly  10  may be joined with other fences (not shown) to become an elongated fence. The molded plastic fence assembly  10  is created when a unitary front fence section  20  and a unitary rear fence section  30  are coupled together. 
     As shown in  FIGS. 2 and 3 , the unitary front fence section  20  has forward side  22 , an inner side  24 , a plurality of partial fence elements  26 . The unitary front fence section partial fence elements  26  each have lateral sides  28 . When the fence elements  12  have generally orthogonal cross-sections (as shown), the unitary front fence section fence element lateral sides  28  are generally perpendicular to the unitary front fence section forward side  22 . If the fence elements  12  have a curved or rounded shape (not shown), the front fence section fence element lateral sides  28  may be considered to begin at a location about 45 degrees from an axis extending normal to the plane of the fence assembly  10 . The unitary front fence section inner side  24  may have one or more interior molding artifacts disposed thereon. The unitary front fence section forward side  22  and front fence section fence element lateral sides  28  are generally, or entirely, free from molding artifacts. 
     The unitary rear fence section  30  has a back side  32 , an inner side  34 , and a plurality of partial fence elements  36 . The unitary rear fence section partial fence elements  26  each have lateral sides  38 . The unitary rear fence section back side  32  and rear fence section fence element lateral sides  38  are generally, or entirely, free from molding artifacts. The unitary rear fence section inner side  34  may have one or more interior molding artifacts disposed thereon. When the unitary front fence section  20  and the unitary rear fence section  30  are coupled together the unitary front fence section partial fence elements  26  and the unitary rear fence section partial fence elements  36  form the fence elements  12  and also define an enclosed space  56 , discussed below. In this configuration, because all interior molding artifacts are disposed on the unitary front fence section inner side  24  and the unitary rear fence section inner side  34 , that is, in the interior space, no interior molding artifacts are visible. 
     Preferably, each element in the unitary front fence section plurality of partial fence elements  26  includes a substantially contiguous perimeter  40 . Similarly, each element in the unitary rear fence section plurality of partial fence elements  36  includes a substantially contiguous perimeter  42 . The unitary front fence section plurality of partial fence elements substantially contiguous perimeter  40  is structured to engage the unitary rear fence section plurality of partial fence elements substantially contiguous perimeter  42 . 
     More preferably, each element in said unitary front fence section plurality of partial fence elements  26  includes a generally planar member  46  having a raised edge  48 . The unitary front fence section plurality of partial fence elements raised edge  48  extends along the substantially contiguous perimeter  40  of each element in the unitary front fence section plurality of partial fence elements  26 . The unitary front fence section plurality of partial fence elements raised edge  48  extends from the unitary front fence section inner side  24 . Similarly, each element in the unitary rear fence section plurality of partial fence elements  36  includes a generally planar member  50  having a raised edge  52 . The unitary rear fence section plurality of partial fence elements raised edge  52  extends along the unitary rear fence section plurality of partial fence elements substantially contiguous perimeter  42 . The unitary rear fence section plurality of partial fence elements raised edge  52  extends from the unitary rear fence section inner side  34 . Further, each planar member  46 ,  50  has an inner side  24 A,  34 A corresponding to the unitary front fence section inner side  24  and the unitary rear fence section inner side  34 , respectively. 
     In this configuration, the coupling of the unitary front fence section  20  and a unitary rear fence section  30  create an enclosed space  56  within selected fence elements  12 . That is, selected fence elements  12  such as, but not limited to the posts  14  and slats  16  are, in a wooden fence, thicker than other elements such as the rails  18 . 
     As shown in  FIGS. 2A and 2B , in a more preferred embodiment, each element in the unitary front fence section plurality of partial fence elements raised edge  48  and in the unitary rear fence section plurality of partial fence elements raised edge  52  includes an extended rib  64 ,  66  that cooperatively engages and corresponds to each other. That is, each of the unitary front fence section plurality of partial fence elements raised edge  48  and each of the unitary rear fence section plurality of partial fence elements raised edge  52  have a face  60 ,  62 . Each unitary front fence section plurality of partial fence elements raised edge face  60  and each unitary rear fence section plurality of partial fence elements raised edge face  62 , preferably, extends generally parallel to the associated planar member inner sides  24 A,  34 A. Each unitary front fence section plurality of partial fence elements raised edge face  60  and each unitary rear fence section plurality of partial fence elements raised edge face  62  have a width. Each of the unitary front fence section plurality of partial fence elements raised edge face  60  and each of the unitary rear fence section plurality of partial fence elements raised edge face  62  further includes an extended rib  64 ,  66 . Each unitary front fence section plurality of partial fence elements raised edge extended rib  64  and each unitary rear fence section plurality of partial fence elements raised edge extended rib  66 , have a width that is less than the width of the associated face  60 ,  62 . Each unitary front fence section plurality of partial fence elements raised edge extended rib  64  and each unitary rear fence section plurality of partial fence elements raised edge extended rib  66  are not aligned with each other. Thus, when the unitary front fence section  20  and a unitary rear fence section  30  are coupled, each of the unitary front fence section plurality of partial fence elements raised edge extended rib  64  engages the unitary rear fence section plurality of partial fence elements raised edge face  62  and, conversely, each unitary rear fence section plurality of partial fence elements raised edge extended rib  66  engages the unitary front fence section plurality of partial fence elements raised edge face  60 . 
     Preferably, each unitary front fence section plurality of partial fence elements raised edge extended rib  64  and each unitary rear fence section plurality of partial fence elements raised edge extended rib  66  each have a width that is about half the width of the edge face  60 ,  62  from which each said rib  64 ,  66  extends. More preferably, the unitary front fence section plurality of partial fence elements raised edge face  60  and the unitary rear fence section plurality of partial fence elements raised edge face  62  each have an inner portion  70 ,  72  and an outer portion  74 ,  76 , respectively. In this configuration, each of the unitary front fence section plurality of partial fence elements raised edge extended rib  64  extends from the unitary front fence section plurality of partial fence elements raised edge face outer portion  74 . Conversely, each of the unitary rear fence section plurality of partial fence elements raised edge extended rib  66  extends from the unitary rear fence section plurality of partial fence elements raised edge face inner portion  72 . 
     As shown in  FIGS. 4 and 5 , the fence assembly  10  further includes a coupling device  80  structured to couple the unitary front fence section  20  and the unitary rear fence section  30 . That is, the coupling device  80  includes a first component  82  and a second component  84  disposed on the unitary front fence section  20  and the unitary rear fence section  30 , respectively. Preferably, the unitary front fence section coupling device first component  82  is disposed on at least one of the unitary front fence section plurality of partial fence elements planar member inner side  24 A. The unitary rear fence section coupling device second component  84  is disposed on at least one of the unitary rear fence section plurality of partial fence elements planar member inner side  34 A. 
     The coupling device  80  may include, for example, a coupling device first component  82  that is a generally circular collar  90  and a coupling device second component  84  that is a generally circular peg  92 . The peg  92  is structured to fit snuggly within the collar  90 . Preferably, the collar  90  has an inner surface  96  having at least one flat portion  98  that is structured to act as a wedge. More preferably, there are three flat portions  98 A,  98 B,  98 C on the collar inner surface  96 . The center of each flat portion  98 A,  98 B,  98 C is disposed about 120 degrees apart about the collar inner surface  96 . The coupling device  80  may also include an adhesive  100  disposed between the unitary front fence section  20  and the unitary rear fence section  30 . The adhesive  100  may, for example, be disposed within each collar  92  so that the collar  92  bonds to an associated peg  90 . 
     While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.

Summary:
A molded plastic fence having a unitary front fence section and a unitary rear fence section is provided. The unitary front fence section and the unitary rear fence section are coupled together to form a fence without visible molding artifacts. To emulate a traditional wooden fence, the fence sections preferably include various fence elements such as posts, slats and rails. The fence elements on each fence section typically have a planar member with an inner side and a raised edge extending from the inner side. The molding artifacts are disposed on the inner sides of the fence elements. The unitary front fence section and a unitary rear fence section are coupled with the raised edges engaging each other. In this configuration the molding artifacts are hidden from view and the fence elements appear as solid.