Abstract:
A fence assembly including a post and interconnecting rails. The post includes an interior chamber structure defined by numerous compartments, an exterior wall structure and a plurality of inwardly projecting rail-receiving channels. The rail-receiving channels at least partially define the geometry of the interior chamber structure. The assembly may be made of extruded plastic material such that the post, rails and additional components, such as channel inserts, are generally hollow along their respective elongate dimensions. Each of the components within the assembly may be cut to user-defined lengths. The purpose of the abstract is to enable the United States Patent and Trademark Office and the public generally to determine from a cursory inspection the nature and gist of the technical disclosure, and is not to be used for interpreting the scope of the claims.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional Application Nos. 60/366,382 filed Mar. 21, 2002, and 60/398,062 filed Jul. 24, 2002. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates generally to fence structures, and more particularly to extruded plastic fence rails and posts that can form connections with one another that improve the ease with which fence assemblies can be fabricated.  
           [0003]    Fences have traditionally been constructed of wood, stone or metal. The use of plastic componentry in fence structures, which typically include posts, rails, pickets and related parts, has been in its ascendancy in recent years due to the ability to manufacture inexpensive, environmentally durable systems. Contributing to the desirability of using plastic fence assemblies is that once installed, they require comparatively little maintenance, such as painting, rust and vermin protection.  
           [0004]    Despite these advantages, plastic fence assemblies continue to suffer from various shortcomings. For example, many of the constructions are overly complex, requiring multiple pieces or hybrid metal/plastic structures, as well as detailed steps to piece together the myriad components. In addition, if all or portions of the fence need to be disassembled for access, maintenance or replacement of damaged parts, the cumbersome process has to be repeated. Moreover, accommodations are often required at the time of fence installation for various contingencies, such as topography of the land and natural or artificial structures that could get in the way of the installation. In such cases, the installer may have to make minor adjustments to the dimensions of the post, rails and inserts. For example, an installer, especially if working alone, is faced with the difficult, if not impossible task of establishing a neat, secure assembly unless there are features built into the rails or posts to secure the two while determining placement of other components, such as subsequent posts. This task is exacerbated when additional component reinforcement, in the form of metal structure surrounded by plastic sleeves or covering, is used, as the additional weight makes the maneuvering of long parts (such as rails) even more unwieldy. Furthermore, once installed, the fence posts can be subject to rotational movements about its vertical axis unless they are adequately secured into the ground.  
           [0005]    The present inventors have recognized a need for extruded plastic fence assemblies that are made up of components that are inexpensive to manufacture. They have further recognized a need for features within the components of the fence assembly that facilitate the rapid, secure anchoring of the components to one another, as well as to a mounting surface, such as the ground.  
         SUMMARY OF THE INVENTION  
         [0006]    According to an aspect of the present invention, a post defined by a generally hollow construction along its elongate axis is disclosed. The post includes an exterior wall structure, an inwardly projecting elongate rail-receiving channel formed into the exterior wall structure and a channel insert disposed in the channel. Each of the inserts include an outwardly-facing exterior surface and an inwardly-facing interior surface opposite the exterior surface. The channel and insert are configured to define an insert securement to restrict movement of the insert along the direction of the channel depth. The securement is disposed closer to the insert&#39;s exterior surface than its interior surface.  
           [0007]    Optionally, the securement is defined at least in part by the exterior wall structure of the post. In another option, the securement is made up of a plurality of laterally-spaced tabs disposed on the insert and a throat defining a plurality of slots is disposed in the channel. The slots of the throat accept the tabs to secure the insert to the channel. Preferably, the tabs are disposed substantially adjacent the exterior surface so that precise dimensional control between otherwise spaced-apart components is not required. In the present context, the term “substantially” refers to an arrangement of elements or features that, while in theory would be expected to exhibit exact correspondence or behavior, may, in practice embody something slightly less than exact. As such, the term denotes the degree by which a quantitative value, measurement or other related representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. In a similar vein, each tab is spaced away from the exterior surface by an amount not greater than the thickness of the tab. Additionally, the exterior surface connects to the tabs via transition zone in the insert in one of at least three ways, including one that is bevelled outward, one that is bevelled inward, and one that connects through a right-angle transition zone. In another option, the insert is of substantially hollow construction, while in another still, the insert is shaped to form a substantially flush surface with the exterior wall structure, giving the post an aesthetically-pleasing appearance. In another option, the insert comprises a depth-wise dimension that is significantly smaller than the depth of the channel. In one embodiment, the significantly smaller depth-wise dimension of the insert is less than half of the depth of the channel. In an additional option, a rigid support pole is coupled to the post to provide increased resistance to rotation of the post about the post&#39;s elongate axis when the post and the rigid support pole are coupled to a mounting surface.  
           [0008]    According to another aspect of the invention, a fence assembly is disclosed. The assembly includes a post as previously described plus at least one rail disposed in the channel. Optionally, the fence assembly includes a plurality of rails. Furthermore, at least two of the plurality of rails are disposed in the channel and vertically spaced relative to one another by at least one of the inserts. In addition, the rail defines an exaggerated surface that protrudes from a lateral surface on the rail end, the exaggerated surface configured to engage the securement. In one form, the exaggerated surface comprises a hinged flap, where more particularly, the hinged flap is integrally formed with the rail to define a unitary construction. As with the previous aspect, a rigid support pole can be coupled to the post. To additionally secure the rail once its end is disposed in the channel, the rail defines apertures in its end such that the apertures are substantially vertically-aligned relative to one another. A securing pin can be passed through the apertures and the inserts. In addition, the securing pin and post can be secured to a mounting surface (such as the ground, plate, platform or related structure) to inhibit translational rail movement along the rail&#39;s longitudinal axis when the rail is disposed in the channel and the securing pin is positioned through the apertures.  
           [0009]    According to another aspect of the invention, a fence assembly is disclosed. The fence assembly includes a post defined by a generally hollow construction along its elongate axis with an exterior wall structure and an inwardly projecting elongate channel formed into the exterior wall structure, at least one rail disposed in the channel, and a securing pin disposed within apertures formed in the ends of the rail. The securing pin is configured to mount to a mounting surface to inhibit translational movement of the rail similar to that of the previous aspect. Optionally, the fence assembly further includes an insert securement disposed in at least one of the channels, the securement defining a narrowed throat region configured to further restrain translation of the rail disposed in the channel. The narrowed throat region defines a plurality of slots therein. In another option, at least one channel insert can be placed into a rail-receiving channel, where the insert configuration is similar to that of the previous aspects. As previously discussed, the inserts can be substantially hollow such that the securing pin is configured to pass through the hollow portion of the insert. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0010]    The following detailed description of the preferred embodiments of the present invention can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:  
         [0011]    [0011]FIG. 1 illustrates a top view of a fence assembly according to an aspect of the present invention;  
         [0012]    [0012]FIG. 2 illustrates a perspective view of a fence post and two channel insert variants;  
         [0013]    [0013]FIG. 3 illustrates a perspective view of a section of fence using the fence assembly of FIG. 1;  
         [0014]    [0014]FIG. 4 illustrates the positioning of the rails, channel inserts, a rigid support pole and end cap relative to the fence post shown in FIG. 1;  
         [0015]    [0015]FIG. 5 illustrates a top view of an alternate fence post configuration, showing the addition of a rigid support pole inserted therein;  
         [0016]    [0016]FIG. 6 illustrates a top view of another alternate fence post configuration;  
         [0017]    [0017]FIG. 7 illustrates the fence post of FIG. 6, including a rail, channel inserts and a rigid support pole offset-mounted along the post&#39;s elongate axis; and  
         [0018]    [0018]FIGS. 8A through 8C show the various channel inserts that can be used with the fence post of FIG. 6. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]    Referring first to FIG. 5, a top view of a post  10  according to an embodiment of the present invention is shown. Post  10  may be formed into a single, unitary construction from a plastic material (such as polyvinyl chloride (PVC)) by known methods (such as extrusion) and as such, defines an extrudable cross sectional profile. In the present context, a structural member defines an extrudable cross sectional profile if respective cross sections of the member, taken along a length or width-wise axis of the member, each define substantially identical dimensions. In such case, the member defining the extrudable profile may be produced by an extrusion process where a semi-soft plastic is forced through the orifice of an extrusion die to produce a continuously formed piece having a cross-sectional shape defined by the orifice or other shaping members downstream of the orifice. It is contemplated that a structural member having an extrudable cross-sectional profile may also include portions along its axis that are subject to post extrusion cutting, drilling, bending, deforming or related operations. Post  10  includes an interior chamber structure  15  made up of numerous hollow, elongate compartments  80 ,  82 ,  84  and  86  the last three of which are offset from and substantially parallel with a post centerline defined along a longitudinal (elongate) axis. By having the pole-receiving compartment  86  offset from the post centerline and at least partially against outer wall  12 , it is easier for an installer to place the post  10  directly on a property line and without recourse to visual estimation, as the post side adjacent the pole/compartment combination can be placed closest to such property line. The post  10  is also made up of an exterior wall structure  12  and numerous inwardly projecting elongate rail-receiving channels  20  formed into exterior wall structure  12 . Interior wall structure  14  defines the boundary between the rail-receiving channels  20  and the various compartments  80 ,  82 ,  84  and  86 . This commonality allows each of the channels  20  to partially define the interior chamber structure  15 . An interface in the form of a locking mechanism  60  is defined between the channel  20  and the exterior wall structure  12  such that channel  20  can engage a complementary end surface of a rail (as shown and described below) to substantially prohibit translation of the rail along its longitudinal dimension once the rail and channel are engaged. In the configuration shown, locking mechanism  60  includes a pair of lateral detents that form a throat in channel  20  to provide a narrowed contact region.  
         [0020]    At least one compartment  86  is made up of a plurality of projections  45  that can engage a rigid support pole  50 . Together, the projections and rigid support pole  50  define a pole-engaging axis that is parallel to the longitudinal, or elongate, axis of post  10 , but radially offset relative to the post centerline. By coupling the pole  50  to the post  10  and having both secured to a mounting surface, such as the ground (not shown), a reinforced post is formed that exhibits increased resistance to torsional forces acting on it, thereby maintaining proper post orientation. Resistance to rotation is important to maintaining the integrity of a fence assembled with posts  10 , as forces due to weather or animal, human or related contact otherwise would have a tendency to cause the rails and posts to shift relative to one another, causing the assembly to come apart. The rigid support pole  50  is shaped to include non-axisymmetric features to improve the tightness of the fit between rigid support pole  50  and the projections  45  that are formed in the offset compartment  86 . In the configuration shown, rigid support pole  50  is substantially T-shaped, such that its various radial detents  51 ,  52 ,  53  and  54  fit in narrowly-defined spaces  40  formed by substantially triangular-shaped projections  45 . It will be appreciated by those skilled in the art that while the projections  45  are shown as being triangular-shaped, the invention is not so limited, as other shapes configured to securely engage the rigid support pole  50  would also suffice. The projections  45  can be integrally formed with the remainder of post  10  through the aforementioned extrusion process. Moreover, the T-shape of the rigid support pole  50  is such that the interlocking fit between the detents  51 ,  52 ,  53  and  54  is only possible over a substantially singular angular orientation about the reinforcing axis. This sort of “keyed” connection ensures that the post  10  and rigid support pole  50  are placed in proper angular orientation to one another, subject only to the tolerance in the space  40  between the rigid support pole  50  and the projections  45 . The longitudinal dimension of the rigid support pole  50  extends along a substantial length of the post  10 , plus an additional distance beyond the lowermost portion of post  10  to ensure secure anchoring into the ground or other mounting surface.  
         [0021]    Referring next to FIGS. 2 and 3, details of connection between the post  10  and rails  30  and channel inserts  70 A,  70 B are shown. In the present figure, the post  10  is structurally similar to that shown in FIG. 5, except for the lack of pole-engaging features in compartment  86 . It will be appreciated by those skilled in the art that either variant can be employed, depending on individual user needs, such as how much torsional resistance is required. Referring with particularity to FIG. 2, two variants  70 A,  70 B of the inserts, as well as how they fit into channel  20  of post  10 , are depicted. The first variant  70 A, with its conventional box shape, emphasizes simplicity of structure and manufacture, while the second  70 B, with its additional faceted surfaces to produce a step structure complementary with that of the throat in channel  20  (as shown in FIG. 1 and discussed below), is used to provide a smooth, flush finish with outer wall structure  12 . Referring with particularity to FIG. 3, in addition to providing an aesthetically-pleasing finished surface to post  10 , the inserts  70 A,  70 B (only the latter presently shown) maintain vertical spacing between rails  30 , providing both a neat finished product and additional resistance to rail  30  movement. The construction of post  10  is such that it can function equally well as an end post, corner post or intermediate post, the last two being shown in the figure. As with the post  10 , the inserts  70 A,  70 B are extrudable, and in situations where made of plastic, can be easily cut to any desired length. Similarly, rails  30  can be made from plastic such that they can be cut to desired lengths, and extrudable such that they can be produced economically in large quantities. As with the fit between the channel  20  and rails  30  described above, locking mechanism  60  may also be used to engage a complementary surface on the inserts  70 A,  70 B.  
         [0022]    Referring next to FIG. 1, a top view showing connection details of a fence assembly constructed using the post  10 , rails  30  and channel insert  70 B of FIGS. 2 and 3 is shown. Two of channels  20  of post  10  are shown engaged to rails  30 , while a third has a channel insert  70 B disposed therein. In the present figure, the post  10  is used as a corner post, such that inserts  70 B provide flush surface finish features for channel  20  not being used. The faceted surfaces of insert  70 B complement those the locking mechanism  60  formed at the throat of channel  20  such that the insert  70 B cannot be removed other than by sliding it out along the elongate axis of post  10 . The gaps shown between inner wall  14  and insert  70 B are shown exaggerated for clarity; it will be appreciated by those skilled in the art that tolerances can be made much tighter to ensure a secure, relatively smooth surface finish. Each of the rails  30  show a different protrusion extending laterally from the ends of the rails  30 . In the present context, the “end” of the rail  30  includes not just the remote edge, but all portions of rail  30  that are designed to fit into the channel  20 . These protrusions are sized to allow a locking interconnection between the rails  30  and the locking mechanism  60  of channels  20 . In one variation, the rail  30  includes a pair of pins  37  that are axially aligned with one another so that the lateral dimension of rail  30  is greater than throat produced between locking mechanisms  60 . Thus, once the rail  30  is disposed in channel  20  (such as by aligning the rail end with channel  20  and dropping the rail  30  down into the channel along the elongate axis of post  10 ), the interference fit between pins  37  and locking mechanism  60  prohibits movement between them, save the movement equal to the relatively small gap G, which, like the gap earlier described between the between channel  20  and insert  70 B, is shown exaggerated for clarity. In another variation, the rail  30  includes a pair of flaps  33  integrally formed in the opposing lateral walls. Flaps  33  are shown as rectangular members defined by cut-outs on three sides such that when the rail is ready to be placed in channel  20 , the flaps can be bent away from the rails  30  to provide an interference fit similar to that described for the pins  37  above. In addition to the protrusions in the form of flaps  33  and pins  37  to allow a locking interconnection between the rails  30  and the locking mechanism  60 , rail  30  can include a securing pin  95  placed vertically through apertures  35  in the end of the rails  30 . Details of the securing pin will be discussed in conjunction with FIG. 4 below.  
         [0023]    Referring next to FIG. 4, a perspective view of the details of the fence assembly of FIG. 3 is shown. The assembly highlights how the inserts  70 B act not only top establish a smooth surface finish along the exterior wall structure of post  10 , but also vertical spacing between rails  30 . In addition to the post  10 , rails  30  and channel inserts  70 B, the above-mentioned securing pin  95  is shown. The hollow nature of the inserts  70 B along the longitudinal dimension of securing pin  95  improves the ease of pin placement through apertures  35  in the ends of each rail  30 . The securing pin  95  can be configured to be long enough to extend through all of the inserts  70 B and the ends of rails  30  stacked with the inserts, and can, like the rigid support pole  50  (shown in FIG. 5), extend into a mounting surface, such as the ground. The fence assembly also includes a cap  90  releasably connected to the top of post  10 . Not only does this improve post aesthetics, it prevents debris and moisture from accumulating in the interior chamber structure of post  10 .  
         [0024]    Referring next to FIGS. 6 and 7, a top view of an alternate embodiment of the post and a reinforced fence assembly, respectively, are shown. As with the previous embodiment, numerous hollow, elongate compartments  180 - 190  define an interior chamber structure, including a trapezoidal-shaped pole-receiving compartment  186  with projections  145 . In addition, as shown with particularity in FIG. 6, post  110  includes a removable channel cover  113  integrally formed across at least one of the rail-receiving channels  120  to form a substantially flush surface with exterior wall structure  112 . One or more lines of weakness  115  are formed into exterior wall structure  112  such that cover  113  can be easily removed. In one form, the lines of weakness are made up of score lines. The cover  113  preserves the smooth appearance of the exterior wall structure  112  until such time as access to the channel  120  disposed below the cover  113  is required. The lines of weakness  115  permit a user to easily remove the cover  113  with a conventional utility knife or the like. In addition, insert securement  160  shows a variation of locking mechanism  60  shown in FIG. 5, where it now defines an interface between the exterior wall structure  112  and channel  120  that includes two pair of lateral detents such that not only does securement  160  define a throat in channel  120 , but also an additional slot  161  for receiving a complementary surface on inserts  170 A,  170 B and  170 C (shown and described below). Referring with particularity to FIG. 7, rigid support pole  150  (still possessive of a substantially T-shaped construction similar to the one shown in FIG. 5) can fit in a particular angular orientation relative to the projections  145  and pole-receiving compartment. It will be appreciated by those skilled in the art that other rigid support pole  150  configurations are possible, including cylindrical and non-axisymmetric configurations. For example, a plurality of cylindrical poles (not shown) can be used, each disposed within each of the various semi-autonomous spaces formed by the projections  145 . An additional pole (not shown) could be placed within pole-receiving compartment  186  adjacent the exterior wall structure  112  such that the plurality of poles provide additional support. Also as with the previous embodiment, the pole-receiving compartment  186  is disposed offset relative to the centerline of post  110 , disposed against the exterior wall structure  112  so that the entire assembly can be accurately placed along the property line. Tabs (shown and described below) on the inserts  170 B promote a secure fit with securement  160 . Also as shown in FIG. 7, the stacking of rail  130  on top of insert  170 B in the same channel  120  is highlighted. It will be appreciated by those skilled in the art that although the present invention shows particular components depicted within two separate embodiments, it can embody any combination of the aforementioned interior chamber structure, pole-receiving compartment structure, securement configuration, and rail end and channel insert construction.  
         [0025]    Referring next to FIGS.  8 A- 8 C, details of various embodiments of channel inserts  170 A,  170 B and  170 C are shown. All three include tabs  172 A,  172 B and  172 C, respectively, that are disposed adjacent an outermost face of the inserts and used to engage the slot  161 . As such, the slot  161  and any one of tabs  172 A- 172 C together make up securement  160  (as shown previously in FIG. 7). It will be appreciated by those skilled in the art that while what is referred to herein as securement  160  is made up of laterally-disposed slots  161  formed into the post  110  with corresponding tabs  172 A- 172 C that extend from the lateral ends of the inserts  170 A- 170 C, slot  161  could alternately be disposed in the inserts  170 A- 170 C, while the tabs  172 A- 172 C could be disposed on the throat  160 . The nature of securement  160  is to be broadly construed to include both variants. The tabs  172 A-C, in conjunction with the relatively thin depth-wise profile of the insert  170 A-C, allow manufacturing tolerances to be relaxed on the inserts. By having the depth-wise distance from the outermost face to the tabs  172 A-C kept to a minimum, precise dimensional tolerances for the securement  160 , the tabs  172 A-C and transition zones  171 A-C between the insert outermost faces and the tabs is not required. The three insert configurations shown highlight different transition zones along the outermost face, including a transition zone  171 A bevelled inward (FIG. 8A), right angle transition zone  171 B (FIG. 8B) and transition zone  171 C bevelled outward (FIG. 8C). The locking between the tabs  172 A-C and slots  161  (shown in FIGS. 6 and 7) relieves the requirement of having large depth-wise insert dimensions to ensure adequate coupling between the insert and channel. Thus, unlike conventional inserts, where the relatively large depth-wise dimension necessitates manufacturing to a relatively tight tolerance to ensure a good fit between the insert and the channel, the present inserts  170 A-C are constructed to allow for some dimensional variation.  
         [0026]    Having described the invention in detail and by reference to preferred embodiments thereof, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. More specifically, although some aspects of the present invention are identified herein as preferred or particularly advantageous, it is contemplated that the present invention is not necessarily limited to these preferred aspects of the invention.