Patent Publication Number: US-2007120035-A1

Title: In-ground anchor structure for interchangeable posts and signs

Description:
RELATED APPLICATION DATA  
      This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/736,080, filed Nov. 10, 2005. 
    
    
     FIELD OF THE INVENTION  
      The present invention generally relates to embedded ground anchors, and in its preferred embodiments more specifically relates to an anchor to be embedded in the ground for supporting posts of various configurations and sizes for any purpose, either permanently or temporarily.  
     BACKGROUND OF THE INVENTION  
      The placement of both temporary and permanent signs for a variety of purposes is commonplace. It is common for temporary signs to be erected for a period of time, removed, and either the same sign or another sign to be erected in the same location at another time. Permanent signs may be renewed or replaced from time to time with another sign structure. The conventional method of placing a sign involves excavating a hole for each sign post, placing the sign post(s) in the holes, and filling around the post with the excavated soil or with concrete. This approach is not only labor intensive and time consuming, but also damaging to lawns and the like where the signs are placed. Temporary signs are often erected by pushing or driving one or more relatively thin posts or rods into the ground, which is easier and less disruptive, but also much less secure. It would be advantageous to place a support structure or anchor in the ground, and to attach above ground sign posts or the like to the anchor structure.  
      Various designs and approaches to providing such anchors are known in the prior art. In some designs the anchors are driven into the ground, and in other designs the anchors are placed in the conventional manner, by excavation and fill. Although anchor devices and structures known in the prior art provide effective support, they remain subject to significant limitations and disadvantages. Most of the designs known in the prior art are limited to use with a specific post configuration and dimension. A few designs are able to accommodate posts with limited variation in size, but not in configuration. Prior art anchors designed for use with square posts cannot be effectively used with round posts, and vice versa.  
      Support posts for, especially, professionally produced signs are provided in both square and round configurations, and in different sizes. It is desirable for an anchoring system to accommodate all common configurations and sizes. It is also desirable for an anchoring system to be easily adaptable to the use of other configurations and sizes without the need to replace the entire anchor structure. It is further desirable for an anchor structure to be unobtrusive when not in use to support a sign, without above ground obstructions that present a trip hazard and make maintenance chores such as mowing more difficult and potentially dangerous.  
     SUMMARY OF THE INVENTION  
      The present invention provides a secure anchor structure that may be easily placed in the ground with minimal disruption of the location in which it is positioned, that can accommodate posts of several sizes and configurations with the same post receiver assembly, and that may be readily adapted to additional post sizes and configurations by interchanging post receiver assemblies on the same ground anchor assembly.  
      The anchor structure of the invention includes a ground anchor assembly and a post mounting assembly removably connected to the ground anchor assembly, allowing the ground anchor assembly to be installed without interference from or the potential for damage to the post mounting assembly. In the preferred embodiment the ground anchor assembly includes an elongate ground penetrating spike, with a mounting plate at its upper end and with stabilizing fins connected to and extending outwardly from the spike, which is to be driven into the ground until the mounting plate is flush with or slightly below the surface.  
      The post mounting assembly includes a base plate, to be connected to the mounting plate of the ground anchor assembly, and a post receiver for connection of a sign post. The post receiver is provided in a variety of configurations and dimensions to accommodate commonly used post configurations and dimensions. Alternatively, a dual post receiver, structured to receive and connect posts of several configurations and dimensions, may be utilized.  
      In an alternative embodiment the ground anchor assembly is formed with a screw shaft and a spiral screw plate instead of spike and fins, and is installed by screwing the ground anchor assembly into the ground until its mounting plate is at the desired elevation for connection of the post mounting assembly.  
      The structure and features of preferred and alternative embodiments of the anchor structure of the invention will be described in detail with reference to the accompanying drawing figures. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an elevation view showing two units of a preferred embodiment of the anchor structure of the invention in place and supporting a two post sign.  
       FIG. 2  is a side elevation view of the ground anchor assembly of a preferred embodiment of the anchor structure of the invention.  
       FIG. 3  is a top plan view of the ground anchor assembly shown in  FIG. 2 .  
       FIG. 4  is a top plan view of one embodiment of the post mounting assembly of the anchor structure of the invention.  
       FIG. 5  is a side elevation view of the post mounting assembly shown in  FIG. 4 .  
       FIG. 6  is a top plan view of another embodiment of the post mounting assembly of the anchor structure of the invention.  
       FIG. 7  is a side elevation view of the post mounting assembly shown in  FIG. 6 .  
       FIG. 8  is a top plan view of a different embodiment of the post mounting assembly of the anchor structure of the invention.  
       FIG. 9  is a top plan view of yet another embodiment of the post mounting assembly of the anchor structure of the invention.  
       FIG. 10  is a side elevation view of the post mounting assembly shown in  FIG. 9 .  
       FIGS. 11, 12 , and  13  are cross-sectional illustrations of common configurations for prefabricated posts.  
       FIG. 14  is a side elevation view of an alternative embodiment of the ground anchor assembly.  
       FIG. 15  is a top plan view of the alternative embodiment of the ground anchor assembly shown in  FIG. 14 .  
       FIG. 16  is an elevation view showing a preferred embodiment of the ground anchor assembly partially driven into the ground within a shallow excavation.  
       FIG. 17  is an elevation view illustrating placement of the post mounting assembly and a post on a fully installed ground anchor assembly.  
       FIG. 18  is an elevation view showing the alternative embodiment of the ground anchor assembly partially screwed into the ground, and also showing a T-handle driver used for installation.  
       FIG. 19  is an elevation view of an installed anchor structure of the alternative embodiment, supporting a post and sign. 
    
    
     DESCRIPTION OF THE INVENTION  
      The anchor structure of the invention includes a ground anchor assembly  10  and a post mounting assembly  11 , which is removably connected to the ground anchor assembly. In the preferred embodiment, ground anchor assembly  10  includes an elongate ground penetrating spike  12 , with a first, upper end  13  and a second, lower end  14 . The preferred length of spike  12  is approximately twenty-four inches, but it is to be understood that the specific length of the spike is not critical to the scope of the invention, and other lengths may be readily used to accommodate different installation requirements and conditions.  
      A plurality of fins  15  are connected to spike  12  adjacent to its upper end  13  and extending along the length of the spike toward its lower end. Fins  15  are preferably right triangular plates disposed with the base  16  of each triangle adjacent to the upper end of spike  12  and extending outwardly perpendicular to the longitudinal axis of the spike. In the preferred embodiment the number of fins  15  is four, and the fins are symmetrically arrayed around spike  12 . The number of fins is not critical to the scope of the invention, however, and other numbers and arrangements of fins  15  could be used. It is preferred that at least three fins be used, to maintain the stability of the ground anchor when embedded in the ground. In the preferred embodiment the length of fins  15  between the base and the apex  17  of the triangle be approximately one third the length of spike  12 , but other proportional relationships could be used. Likewise, although the triangular fin configuration is preferred, other configurations could be used within the scope of the invention.  
      A mounting plate  18  is connected to the upper end  13  of spike  12 , and preferably also connected to the base  16  of each fin  15 . Mounting plate  18  is preferably a circular disk, with a diameter somewhat larger than twice the length of each fin base  16 , centered on spike  12  and disposed perpendicular to the longitudinal axis of spike  12 . The connection between the mounting plate and the spike and fins is preferably made by welding, but other means of connection could be used so long as a secure connection between the mounting plate and spike is formed. As a non-limiting example, mounting plate  18  could be provided with a central aperture and connected to spike  12  by a bolt extending though the central aperture and into a threaded aperture at the upper end of the spike. Mounting plate  18  is penetrated by a plurality of apertures  19  disposed around the plate inward from its outer edge  20 . In the preferred embodiment the number of apertures  19  is four, but the specific number is not critical to the invention.  
      Post mounting assembly  11  includes a base plate  21  and a post receiver  22 . Base plate  21  is preferably formed as a circular disk approximately equal in diameter to mounting plate  18 , and includes a plurality of apertures  23  disposed around the plate inward from its outer edge  24 . Apertures  23  are positioned to align with apertures  19  when base plate  21  is placed on mounting plate  18 . Apertures  23  are preferably formed as slots, so that the alignment between apertures  23  and apertures  19  is maintained when base plate  21  rotated through a few degrees relative to mounting plate  18 , to provide a degree of adjustability in the alignment of the post mounting assembly on the ground anchor assembly.  
      In the embodiment illustrated in  FIGS. 4-7 , post receiver  22  is a square sleeve with a hollow interior  25 , an open first, or upper end  26 , and a second, or lower end  27 . Lower end  27  of the post receiver is preferably open, but could be closed if desired. Post receiver  22  is centered on base plate  21  with its longitudinal axis perpendicular to the base plate, and is firmly connected to the base plate, e.g, by welding, although other secure means of connection could be used. In this embodiment the inside cross-sectional dimensions of the post receiver are slightly larger than the outside cross-sectional dimensions of the posts to be supported. Commonly used prefabricated sign posts are provided in standard configurations and standard sizes. A typical square sign post is three and one fourth inches in outside dimension. A typical round sign post has a diameter of three and one fourth inches. To fit these standard posts, post receiver is square in configuration, with inside cross-sectional dimensions slightly larger than three and one fourth inches, so that these standard posts can be inserted into the hollow interior of the post receiver. Another commonly used prefabricated post type is a square post with cross-sectional dimensions of two inches, and a post receiver with inside cross-sectional dimensions of slightly more than two inches may be used for this post type. These dimensions are standard in the sign industry, but it is to be understood that the components of the anchor structure of the invention can be sized to accommodate posts of any size, and of any configuration. At least one set of aligned bolt apertures  28  are formed in opposed walls of the post receiver near its lower end  27 , to receive an assembly bolt  29  through the interior of the post receiver. Matching apertures are formed in the lower end of the post to be supported by the anchor structure of the invention, to align with apertures  28  when the post is inserted into the post receiver. The close telescoping fit of the post in the post receiver provides secure retention and stability of the post, and the assembly bolt serves primarily to prevent removal of the post from the post receiver. If desired, however, a second set of apertures may be formed in the post receiver and post, offset from apertures  28 , for a second assembly bolt to be placed either perpendicular or parallel to the first assembly bolt.  
      In a variation or alternative embodiment of the post mounting assembly described above, a post mounting assembly with an outer post receiver  22   o  and an inner post receiver  22   i  may be used, as illustrated in  FIG. 8 . The outer post receiver  22   o  is sized to receive three and one fourth inch posts, and the inner post receiver  22   i  is sized to receive two inch posts. In this embodiment apertures  28  extend through both post receivers. Standard prefabricated sign posts are hollow and open at their lower end, so the inner post receiver  22   i  will be received in the interior of a three and one fourth inch post without interference. When a two inch post is used a collar (not shown) may be installed to fill the gap between the post and the upper end of outer post receiver  22   o . Again, it is to be understood that the stated dimensions are used as examples and are not limiting of the scope of the invention.  
      In another variation or alternative embodiment, shown in  FIG. 9 , post receiver  22  is replaced with a dual receiver  30 . The receiver of this embodiment is desired to accommodate large (e.g., three and one fourth inch) square posts and round posts, and small (e.g., two inch) posts without interchanging the post mounting assembly. Receiver  30  includes an outer cylindrical tube  31  and an inner square tube  32  extending upward from base plate  21  in concentric orientation with tube  32  in the interior of tube  31 . The outside diameter of tube  31  is slightly less than the interior cross-sectional dimension of, e.g., a three and one fourth inch hollow post. The inside dimension of tube  32  is slightly greater than the outside dimension of, e.g, a two inch post. Apertures  28  are formed in receiver  30  to receive an assembly bolt  29  as described above. The circular cross-sectional configuration of tube  31  allows it to be received in the interior of both a round post and a square post and assure secure retention of both post configurations. Many prefabricated sign posts are formed with tabs  33  extending into the hollow interior of the post from the post walls, and grooves  34  may be formed in tube  31  to receive tabs  33  when the post is placed over the receiver. A small, e.g., two inch, post may be inserted into the interior of tube  32 . A collar (not shown) may be used, if desired, to smooth the transition between the post and the upper end of the post receiver when a small post is used. Although it is preferred that receiver  30  be connected to a base plate  21  which is removably connected to mounting plate  18 , receiver  30  could be permanently connected directly to mounting plate  18 .  
      To install a sign, or to mount a post for any desired purpose, utilizing the embodiments of the post anchor structure described above, a shallow excavation is preferably made in the location where each post is to be placed. The purpose of the shallow excavation is to position the upper end of the ground anchor assembly and the lower end of the post mounting assembly slightly below finished ground level, and although preferred is not functionally required. The lower end of spike  12  of the ground anchor assembly  10  is positioned at the center of the post location, and the ground anchor assembly is driven into the ground until mounting plate  18  is near the bottom of the shallow excavation, or near the surface of the ground if the excavation step is omitted. A protective impact plate or other cushioning structure (not shown) may be temporarily connected to the upper end of spike  12  and mounting plate  18  to prevent damage to the ground anchor assembly while it is driven into the ground, and then removed when the ground anchor assembly is set. Once the ground anchor assembly is set and any protective structure used during the driving procedure is removed, post mounting assembly  11  is connected to the ground anchor assembly by placing base plate  21  on mounting plate  18 , aligning apertures  23  with apertures  19 , and securing the assemblies together with bolts or other suitable means. A post is then inserted in or placed over (depending on the embodiment used) the post receiver, and assembly bolt(s)  29  are inserted and tightened, securely and firmly positioning and anchoring the post. As an alternate assembly method the post receiver may be attached to the post first, either in the field or prior to delivery of the post, and the pre-assembled post and post receiver assembly secured to the ground anchor assembly as described above. The shallow excavation is then filled with the removed soil or, if desired, with another material such as gravel or even concrete if a more permanent installation is intended, to fully cover the ground anchor assembly and the lower portion of the post mounting assembly. If a multiple post sign or other structure is being erected, an anchor structure is placed for each post, taking care to properly position and align the anchor structures, and the posts are simultaneously engaged with the anchor structures.  
      When or if a sign or post is to be removed or changed, it is necessary to excavate only the fill material covering the joint between the ground anchor assembly and the post mounting assembly so that assembly bolt(s)  29  can be removed. With the assembly bolt(s) removed the post(s) can be easily lifted from the post mounting assembly. If another sign is to be installed in place of the one removed, the post(s) are engaged with the respective post mounting assemblies as described above, and the fill material replaced, quickly and easily completing the operation. If the existing sign or post is to be removed without immediate replacement, the post mounting assembly  11  can be easily disconnected from the ground anchor assembly and removed, leaving the ground anchor assembly in place for later use. In this situation the upper end of the ground anchor assembly remains below grade or at grade, and presents no physical hazard or visual obstruction.  
      In an alternative embodiment of the anchor structure of the invention, a ground anchor assembly that is screwed rather than driven into the ground is provided. As illustrated in  FIG. 14 , in this embodiment spike  12  and fins  15  are replaced by screw shaft  35  and spiraling screw plate  36 . Mounting plate  18  is connected to upper end  37  of shaft  35  and to the upper end of screw plate  36 . In the illustrated embodiment a post receiver  30  is connected directly to mounting plate  18 . It is to be understood, however, that mounting plate  18  may also be provided with apertures  19  and a removable post mounting assembly  11  of one of the embodiments described above connected to mounting plate  18 . The direct connection of the post receiver to mounting plate  18  is appropriate for a situation in which a sign post for any other purpose is intended to be permanently in place, and the use of a removable post mounting assembly is appropriate for a situation in which the sign or post may be removed without immediate replacement.  
      A protective cover  37 , shown in  FIGS. 14 and 19 , may be used with any embodiment of the anchor structure of the invention to cover and protect the attachment bolt or bolts, which are below grade after the shallow excavation is filled, from corrosion and facilitate removal of a post from the anchor structure.  
      The screw type alternative embodiment of the anchor structure is installed with the post receiver or post mounting assembly in place. A T-handle or other rotating means is engaged in the post receiver, as illustrated in  FIG. 18 , and used to rotate the structure to screw the anchor into the ground to the desired depth. The steps for installing the anchor structure(s) and the post(s) to be supported are essentially the same as described above.  
      The foregoing description of preferred and alternative embodiments of the anchor structure of the invention is intended to be illustrative and not limiting. Further alternative embodiments and variations may be devised within the scope of the following claims.