Patent Abstract:
A connector for a steel fence or the like is provided. The connector is formed from a single, cast metallic piece yet can mount one or multiple adjacent rail sections on a post using only a single mount or piece of hardware attaching the connector to the post. It has a vertical throughbore for receiving the post and a horizontal throughbore that intersects with the vertical throughbore at approximately its mid-point. Each end of the horizontal throughbore forms a receptacle for receiving an end of an associated rail section. A grommet is mounted in each receptacle for centering the associated rail section end in the receptacle, locking the rail section from rotation. The grommet also accommodates limited pivoting of the rail section relative to the connector in both the horizontal and vertical planes, hence, accommodating both inclination and directional changes in the fence.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §119 from U.S. Provisional Patent Application Ser. No. 60/822,584, filed on Aug. 16, 2006 and entitled “Fence Post Connector,” which is herein expressly incorporated by reference in its entirety. 
     
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to fence post connectors and fences buildable therewith. More particularly, the invention relates to a cast metal fence post connector for a so-called steel fence and to a steel fence having those fence post connectors. In addition, the invention relates to methods of making the connector and the fence. 
         [0004]    2. Discussion of the Related Art 
         [0005]    Livestock fences, particularly horse fences, are typically formed from horizontally extending, tubular steel rails mounted on vertical tubular posts anchored to the ground. This “steel fence” is widely considered to be superior to split rail and other types of fences because it is rigid and extremely durable. However, the individual rail sections of the typical steel fence must be welded to the vertical fence posts. This welding requirement adds considerable time and labor to building the fence because a portable welder must be employed to weld the opposite ends of each and every rail to the posts on which it is supported. The welds must then be ground to a smooth finish and painted. The welds are subject to rust and peeling, requiring periodic maintenance for the lifetime of the fence. 
         [0006]    More recently, a non-welded connector for steel fences has been introduced. This connector, known as the “440 Fence” connector, is manufactured by the 440 Fence Company of Aubrey, Tex. It is also the subject matter of U.S. Design Pat. No. 495,434. The 440 Fence utilizes two stacked connectors at each joint. Each connector is generally L-shaped, having a vertical section for slipping over the fence post and a generally horizontal section that receives the end of a rail section. The horizontal section is hinged to the vertical section so as to permit limited pivoting of the horizontal section relative to the vertical section in order to accommodate inclines of the fence. In use at a “mid-joint” of the fence (i.e. a location along the fence in which the rails extend in opposite directions from the fence post), two connectors are stacked in a mirror image fashion such that the vertical sections of the two connectors abut one another and the horizontal sections extend outwardly from the vertical section in opposite directions in alignment with one another. With these connectors, a steel fence can be built without welding—dramatically reducing labor when compared to traditional steel fence construction. Post-assembly maintenance is also dramatically reduced. 
         [0007]    However, the 440 Fence connector still suffers from drawbacks. For instance, its multi-piece hinged construction makes it relatively expensive to produce. In addition, two connectors and a total of six setscrews are required at each mid-joint in the fence. It also does not automatically center the pipe of the rails in the connector. In addition, although it can accommodate significant changes in elevation, it can also permit round or odd shaped corrals due to its ability to be pivoted about the post. 
         [0008]    The need therefore has arisen to provide a simplified connector for fences including steel fences. 
         [0009]    The need has also arisen to provide a connector that can be installed quickly and with minimal effort. 
         [0010]    The need has also arisen to provide a connector that lacks a hinge yet can accommodate adjacent rail sections that are inclined and/or extend in different directions relative to one another. 
       SUMMARY OF THE INVENTION 
       [0011]    In accordance with various aspects of the invention, at least some of the above-identified needs are met by providing, e.g., a cast metal mid-joint connector for a steel fence or the like. The connector is formed from, preferably, a single unitary piece, yet can mount two adjacent rail sections on a post using only a single mount attaching the connector to the post. It preferably has a vertical throughbore for receiving the post and a horizontal throughbore that intersects with the vertical throughbore at approximately its mid-point. Each end of the horizontal throughbore forms a receptacle or socket for receiving an end of an associated rail section. Preferably, the socket is oversized as compared to the rail section. In this configuration, the clearance or “rocking tolerance” provided by the oversized socket enables the connector device to movably house the end of an elongate rail. As one example, the rail section can be multiaxially movable with respect to the socket and/or the remainder of the connector device. The socket can be configured to provide a rocking tolerance of at least about 12 degrees, 15 degrees, 20 degrees, or otherwise as desired, of angular deviation from a neutral position, where the rail extends directly axially from the socket. 
         [0012]    In some implementations, the connector includes a threaded internal boss extending into the vertical throughbore and adapted and configured to receive a setscrew assembly. The setscrew assembly includes a setscrew which can have, e.g., a hardened steel insert, and/or a resilient member extending from an end surface thereof for temporarily fixing the connector to and interfacing with the post. 
         [0013]    An isolating member such as, e.g., a grommet or another elastomeric, polymeric, or otherwise resilient member, is mounted in each receptacle for centering the associated rail section end in the receptacle, locking the rail section from rotation. The grommet also accommodates limiting pivoting or actuation of the rail section relative to the connector in both the horizontal and vertical planes, hence, accommodating both inclination and directional changes in the fence. The grommet can be generally annular or cylindrical with opposing, generally circular side surfaces. The side surfaces can have differently sized openings, each of which opens into a common bore. Preferably, in the complete assemblage, the relatively larger opening is proximate the rail section whilst the relatively smaller opening is distal the rail section. This configuration facilitates the insertion of the rail section through the larger opening and corresponding resists its withdrawal from the smaller opening, whereby the rail section is relatively easy to place into the connector yet relatively more difficult to remove therefrom. 
         [0014]    In some embodiments, the connector and the rail segment are made of dissimilar materials, whereby the grommet electrically isolates the connector and rail from each other. This configuration provides, e.g., a dielectric union between the connector and the rail segment and correspondingly mitigates the likelihood of galvanic-type corrosion event, based on two interfacing dissimilar metals. 
         [0015]    In other implementations, the end of the rail segment includes a projection extending radially therefrom. Such projection can be an integral part of the rail segment or it can be provided by way of, e.g., a cap or other structure connected to the end of the rail. The projection can be a discrete element or can extend about a portion or the entirety of an outer circumferential surface of the end of the rail segment. In any event, the projection provides a mechanical abutment or interference between it and the grommet which prevents the non-desired withdrawal of the rail segment from the connector. 
         [0016]    Other connectors, having the same post mount but specialized receptacle configurations, may be provided for corner or end posts. Yet other connectors can allow post penetration at an angle for extreme slopes. 
         [0017]    Connectors configured as discussed above and elsewhere herein are also provided, methods of making connectors configured as discussed above are also provided, and methods of building fences using various connectors configured as discussed herein are also provided. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings, in which like reference numerals represent like parts throughout, and in which: 
           [0019]      FIG. 1  is perspective view of a fence post connector constructed in accordance with a preferred embodiment of the invention, viewed from in front of, above, and from the left side of the connector; 
           [0020]      FIG. 2  is a front elevation view thereof; 
           [0021]      FIG. 3  is a rear elevation view thereof; 
           [0022]      FIG. 4  is a top plan view thereof; 
           [0023]      FIG. 5  is a bottom plan view thereof; 
           [0024]      FIG. 6  is a left-end elevation view thereof, with the right end being a mirror image of the left end; 
           [0025]      FIG. 7  is an exploded perspective view of the connector; 
           [0026]      FIG. 8  is a sectional plan view showing the connector in use; and 
           [0027]      FIG. 9  is a side elevation view of a section of fence incorporating the connectors of  FIGS. 1-8 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0028]    Referring to  FIGS. 1-7 , a fence post connector  10  constructed in accordance with a preferred embodiment of the invention is illustrated. As seen in  FIGS. 8 and 9 , the connector  10  is configured for use as a mid-joint connector for a steel fence  12  formed from horizontal rails sections  14  and vertical posts  16  formed from steel tubes. The posts  16  and rail sections  14  are typically of a common diameter, most typically 2.875″ or 2.375″. The connector  10  comprises a body  18 , a setscrew assembly  20  for affixing the body  18  to a fence post  16 , and a pair of grommets  22 ,  24 . 
         [0029]    Referring to  FIGS. 1-6 , the body  18  preferably is formed from cast aluminum because aluminum cannot rust. However, the body  18  could be formed from other materials such as cast iron, and could be formed from other processes as well, such as by machining a rolled tube. If it is formed from a cast material, the body  18  is even more preferably formed from casting a semi-solid shot of a thixotropic material such as thixotropic aluminum about a core of a material, such as zinc, that has a lower melting point than the solid to semi-solid transition temperatures of the thixotropic alloy. The core is later melted away to form internal features of the body  18  such as threads, undercuts, etc. Hence, the entire body  18  can be formed without any post-casting machining. This casting process is described, for example, in U.S. Pat. Nos. 6,564,856 and 6,427,755; and U.S. application Ser. No. 10/438,954, filed May 15, 2003, all of which are assigned to the assignee of this application, and the disclosures of all of which are hereby incorporated by reference in their entirety. 
         [0030]    Still referring to  FIGS. 1-6 , the body  18 , which weighs about 1.0 lb (as opposed to 3.7 lbs. if it were formed in cast gray iron), is essentially tubular in shape, having a length of about 7″ and an outer diameter of about 4″. The body  18  has a vertical throughbore  26  for receiving the fence post  16  and a horizontal throughbore  28  that intersects with vertical throughbore  26  at approximately its mid point. Each end of the horizontal throughbore  28  forms a socket  30 ,  32  for receiving an end of an associated rail section  14 . The vertical throughbore  26  is formed from aligned radial openings  34 ,  36  at approximately the longitudinal mid-point of the connector  10 . The vertical throughbore  26  should be slightly larger in diameter than the fence post  16  over which it is adapted to slide. In the illustrated embodiment in which the connector  10  is configured for use with a fence post  16  and rail sections  14  each having an outside diameter of 2.875″, the vertical throughbore  26  has a diameter of 2.92″. The horizontal throughbore  28  should be significantly larger in diameter than the diameter of the ends of the rail sections  14  so as to allow substantial rocking of the ends of the rail sections  14  relative to the post  16 . About 12 degrees to 20 degrees of rocking tolerance is preferred when the rail sections  14  are fully inserted into the corresponding sockets  30 ,  32  in an abutting relationship with the fence post  16  as seen in  FIG. 8 , with a rocking tolerance of 15 degrees being especially preferred. This rocking is accommodated by oversizing the horizontal throughbore  28  and by the flexible grommets  22 ,  24 , described below. In the illustrated example in which the connector  10  is configured for use with rail sections  14  having a diameter of 2.875″, the horizontal throughbore  28  has an inner diameter of about 3.5″, reduced to a minimum of 3.0″ at the grommets  22 ,  24 . The grommets  22 ,  24  are mounted in grooves  40 ,  42  formed in the extreme outer ends of the horizontal throughbore  28 . The grooves  40 ,  42  may, if desired, be circumferentially segmented to form a number of fingers (not shown) for gripping the grommets  22 ,  24 . Finally, a threaded internal boss  50  is formed at the axial mid-point of the connector  10 , circumferentially spaced about 90 degrees from the vertical throughbore  26 , for receiving the setscrew assembly  20 . The threads  52 , like the grooves  40 ,  42  and all undercuts, are preferably formed during the casting and subsequent core melt-out processes, negating the need for any post casting machining. 
         [0031]    Each grommet  22 ,  24  functions to hold the end of the corresponding rail section  14  in place in the corresponding socket  30 ,  32  and to center the rail section  14  end in the socket  30 ,  32  while accommodating the desired side to side and vertical rocking of the rails  14  relative to the connector  10 . Each grommet  22 ,  24  has an outside diameter of 3.67″ and an inside diameter of 2.85″. The grommets  22 ,  24  can be inserted into the grooves  40 ,  42  after the body  18  is inserted. The grommets  22 ,  24  are preferably formed from a rubber material having a hardness of 60 Durometer Shore A. An EPDM elastomer is preferred because of its relatively high resistance to ozone and UV, as well as its toughness and low cost. 
         [0032]    As noted above, steel fences  12  often are constructed from rail sections  14  and fence posts  16  having a diameter of 2.375″. In this case, the entire connector  10  can be downsized to meet the requirements of the smaller rails and posts. For instance, the vertical throughbore  26  has a diameter of 2.42″. The horizontal throughbore  28  has a diameter of about 3.0″, reduced to a minimum of 2.5″ at the grommets  22 ,  24 . 
         [0033]    The setscrew assembly  20  could be formed from or replaced by any number of devices capable of securing the connector  10  to the fence post  16 . In the illustrated embodiment, a single setscrew assembly  20  is employed. As best seen in  FIGS. 7 and 8 , the setscrew assembly  20  preferably comprises a zinc setscrew  54  fitted with a hardened steel insert  56  for gripping the fence post  16 . 
         [0034]    Referring to  FIGS. 8 and 9 , to use the mid-joint connector  10 , the installer simply mounts the connectors  10  at the appropriate heights on the first fence post  16  using the setscrew assemblies  20 , resulting in four spaced connectors on the post  16 , in the case of the four rail fence illustrated in  FIG. 9 . The operator then inserts a rail section  14  into the socket  32  of the lowermost connector  10 , slides a connector  10  over the second post  16 A, and slides that connector  10  down to a position in which the rail section  14  is tilted up at least 5 degrees, which provides sufficient spacing between the end of the rail section  14  and the post  16 A to provide clearance for the end of the rail section  16 A and the opening of the socket  30 . As the installer continues to lower the connector  10 , the end of the rail section  14  become fully inserted into the socket  30  by the time the rail is horizontal, whereupon the installer fastens the connector  10  to the post  16 A using the setscrew assembly  20 . The installer then repeats the procedures for the second and subsequent connectors and rail sections  14  on the post  16 A. The grommets  22 ,  24  hold the rail sections  14  in place without damaging the finish on the rail sections  14 . They also center the rail sections  14  in the connector  10 . Hence, two rail sections  14  are mounted on a post  16  using a single connector  10  and a single setscrew  54 . Comparing post  16  to post  16 A in  FIG. 9 , significant rail inclination and change in direction are accommodated by the grommets  22 ,  24  and the oversizing of the sockets  30 ,  32 . Rail sections  14  can be mounted on corner posts and end posts using  440  Fence connectors or specialized connectors illustrated in the materials collectively attached as Appendix A, the subject matter of which is hereby incorporated by reference in their entirety. Inclinations more severe than that, which can be accommodated by the mid-joint connectors, can be accommodated by specialized connectors, also illustrated in Appendix A. 
         [0035]    The fence post connector configured as described above has many advantages over the 440 Fence connector. For instance:
       It is much easier to produce with the entire body, including the grommet receiving grooves, threads, and undercuts being castable in one step with no post casting machining being required.   Only one connector is required at each joint, as opposed to two with the 440 Fence connector.   Only one setscrew is required to couple two adjacent rail section ends to a fence post, as opposed to six being required for the 440 Fence connector. This reduces damage to the tubing and reduces labor.   The aluminum connector cannot rust.   The connector is much lighter than the 440 Fence connector.   The simplified construction results in labor savings of nearly 30% per installation.       
 
         [0042]    Although the best mode contemplated by the inventors of carrying out the present invention is disclosed above, practice of the present invention is not limited thereto. It will be manifest that various additions, modifications, and rearrangements of the features of the present invention may be made in addition to those described above without deviating from the spirit and scope of the underlying inventive concept. The scope of some of these changes is discussed above. The scope of other changes to the described embodiments that fall within the present invention but that are not specifically discussed above will become apparent from the appended claims and other attachments.

Technology Classification (CPC): 8