Abstract:
A rod clip stand is disclosed which is configured to releasably secure and retain a pair of rods in a perpendicular orientation. The rod clip stand has a cradle portion supporting a first rod and an arched portion supporting a second rod. The rod clip stand is particularly well suited for fabricating a rebar grid used to reinforce concrete flatwork.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/957,921, filed Jul. 15, 2013, and U.S. Provisional Application No. 61/959,623, filed Aug. 29, 2013. The disclosures of these provisional applications are expressly incorporated by reference herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention generally relates to a means for arranging cylindrical elements in a grid or lattice configuration, and more particularly relates to a rod clip stand configured to releasably secure and retain a pair of rods in a perpendicular orientation, and optionally to locate the rods a distance spaced from an adjacent support surface. The present invention is particularly well suited for fabricating a rebar grid used to reinforce concrete flatwork. 
       BACKGROUND OF THE INVENTION 
       [0003]    In certain construction or fabrication applications, it is necessary to assemble a grid or lattice structure from a set of cylindrical element on the job site. One such application is for concrete construction. In particular, reinforcement bar or rebar for short is used as a tension device in reinforced concrete and reinforced masonry structures, to strengthen and hold the concrete in compression. The surface of the rebar may be patterned to form a better bond with the concrete. In concrete flatwork, the rebar is often assembled into grid generally the dimension of the area to be formed with concrete. It is important that the rebar grid be elevated from the existing surface. In addition, it is beneficial to interconnect the individual rebar elements together so that they remain in the desired location as concrete is poured over the grid. Lastly, it is critical that the concrete be able to flow through and around the rebar grid to ensure the absence of any air pockets, voids or other defects that could weaken the final concrete structure. 
         [0004]    It is common for the concrete contractor to assemble this rebar grid on the job site. To do so, the contractor must first join the rebar elements together at the nodes of the grid. In other words at the point where two rebar elements intersect. This may be done by welding or alternately with some sort of fastening element such as wire, cable ties or the like. Once assembled in a grid, the rebar must be supported in an elevated position, typically on stands placed in spaced relation beneath the rebar elements. Alternately, the rebar may be supported in an elevated position first then wire tied, welded, etc. This process of fabricating a rebar grid can be time consuming in that it involves multiple steps, and thus costly from a labor cost standpoint. In addition, this process of fabricating a rebar grid requires that the contractor have an inventory of several parts, namely rebar, fasteners and stands, and thus costly from a material and storage cost standpoint. Accordingly, it is desirable to provide a simple, cost-effective means for fabricating a rebar grid with a minimum of components. In addition, it is desirable to provide a compact coupling element in the form of a rod clip stand which functions to interconnect a pair of rebar element and to elevate the rebar elements above the ground. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention. 
       BRIEF SUMMARY OF THE INVENTION 
       [0005]    The present disclosure provides a clipping system for connecting, elevating and protecting cylindrical elements. The clipping system includes a rod clip stand for assembling a pair of cylindrical elements. The rod clip stand includes a cradle portion having a first cradle with a first concave surface formed therein and a second cradle laterally spaced from the first cradle with a second concave surface formed therein. The cradle is configured to receive a first cylindrical element such as a rebar element. The rod clip stand also includes an arched portion interconnecting the first and second cradles in a spaced relationship. The arched portion has a third concaved surface formed at a crown of the arched portion and configured to receive a second cylindrical element such as another rebar element. The third concave surface is generally perpendicular to the first and second concave surface such that the rebar elements are arranged in a generally perpendicular manner. The clipping system may be used in various applications including but not limited to assembling and supporting rebar when fabricating concrete structures. 
         [0006]    The present disclosure also provides an assembly forming a rebar grid with a plurality of rebar elements connected with a rod clip stand at the nodes of the grid. The rod clip stand includes a cradle portion having a first cradle with a first concaved surface formed therein and a second cradle laterally spaced from the first cradle with a second concaved surface formed therein. A first rebar element is supported in the first and second concave surfaces. An arched portion interconnects the first and second cradles in a spaced relationship. The arched portion has a third concaved surface formed at a crown of the arched portion. The third concave surface is generally perpendicular to the first and second concave surface axis and supports a second rebar element. A leg extends from the cradle portion opposite the arched portion. The leg preferably includes a first leg extending from the first cradle and a second leg extending from the second cradle. The rod clip stand couples the first rebar element to the second rebar element is generally perpendicular to on another. 
         [0007]    The simple unitary design of the rod clip stand is lightweight and significantly reduces the amount of material compared to that used in conventional rebar support chairs. The rod clip stand can be a plastic molded part arranged in chains of 16 units. These chains can be nested and stacked such that over 7000 units fit into a standard 2 ft×2 ft×2 ft box, thereby reducing storage volume and shipping cost. One or more chains can be carried on a belt so that a reinforcing ironworker or rod buster can quickly and efficiently fabricate a lattice or grid structure using these rod clip stands. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and: 
           [0009]      FIG. 1  is a perspective view of a rod clip stand in accordance with the present disclosure; 
           [0010]      FIG. 2  shows the rod clip stand illustrated in  FIG. 1  supporting two rods in a generally orthogonal orientation; 
           [0011]      FIG. 3  is a front elevation of the rod clip stand shown in  FIG. 1 ; 
           [0012]      FIG. 4  is a rear elevation of the rod clip stand shown in  FIG. 1 ; 
           [0013]      FIG. 5  is a left side elevation of the rod clip stand, it being understood that the right side elevation is a mirror image thereof; 
           [0014]      FIG. 6  is a top plan view of the rod clip stand; 
           [0015]      FIG. 7  is a bottom plan view of the rod clip stand; 
           [0016]      FIG. 8  is a top plan view showing a lattice of rod elements with a rod clip stand at each intersection forming a node; 
           [0017]      FIG. 9  is a perspective view showing 16 rod clip stands interconnected to form a chain; and 
           [0018]      FIG. 10  is a top plan view showing 14 chains of rod clip stands nested together for packaging and shipping. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    The following detailed description of the invention is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the following detailed description of the invention. 
         [0020]    With reference now  FIGS. 1-7 , a rod clip stand  10  is illustrated which interconnects and supports a pair of rod elements  12 ,  14  in a generally orthogonal or perpendicular arrangement. As seen in  FIG. 8 , a plurality of rod clip stands  10  can be used to assemble a lattice or grid of rod elements  12 ,  14 . In this regard, a rod clip stand  10  couples the rod elements  12 ,  14  together at each node, or in other words at each point where the rod elements  12 ,  14  intersect. The rod elements  12 ,  14  may be reinforcing bars or rebar used to support and strengthen concrete structures. The rod clip stand  10  may have utility in other applications such as pipe, conduit, etc. for fabricating a lattice or grid structure. 
         [0021]    Referring again to  FIGS. 1-7 , the rod clip stand  10  includes a cradle portion  16  having a first cradle  18  defined by a first concave surface  18   s  and second cradle  20  is laterally spaced from the first cradle  18 . The second cradle  20  is defined by a second concave surface  20   s.  As best seen in  FIG. 2 , the cradle portion  16  is configured to receive rod element  12 . The rod clips stand  10  also includes an arched portion  22  interconnecting the first and second cradles  18 ,  20  in a spaced relationship. The arched portion  22  includes a third concave surface  24   s  formed at a crown  24  of the arched portion  22 . As best seen in  FIG. 2 , the arched portion  22  is configured to receive the rod element  14 . The rod clips stand  10 , and in particular the generally perpendicular orientation of the third concave surface  24   s  with respect to the first and second concave surface  18   s,    20   s,  orients the rod elements  12 ,  14  in a generally perpendicular manner. The centroid  26  of the first concave surface and the centroid  28  of the second concave surface lie in a common plane defined by the X-Z axes shown in  FIGS. 3-5 . 
         [0022]    Rod clip stand  10  further includes leg portions  30 ,  32  extending from the first and second cradles  18 ,  20 . A centerline of the leg portions  30 ,  32  lie in a common plane with the centroid  26  of the first and second concave surface  18   s,    20   s  and the centroid  28  of the third concave surface  24   s  as best seen in  FIG. 5 . Similarly, the centroid  28  of the third concave surface bisects the distance between the first and second leg portions  30 ,  32  as best seen in  FIGS. 3 and 4 . In this way, any load on the rod elements  12 ,  14  is transferred through the rod clips stand  10  in a balanced manner. 
         [0023]    The spaced relationship of the first concave surface  18   s  and second concave surface  20   s  ensures that the rod clip stand  10  has at least two points of contact with rod element  12 . As presently preferred, the third concave surface  24   s  is also configured to have at least two points of contact with rod element  14 . Various structural features may be included in the third concave surface  24   s  to provide for at least two points of contact. For example, as shown in  FIG. 7 , a plurality of protrusions  34  (shown in broken lines) may be formed on and extend from the third concave surface  24   s.  A local feature such as protrusions  34  insures that the rod clip stand  10  contacts of the rod element  14  at more than one point. For example, on rods that have ribs, such as rebar, the protrusions may rest in between the ribs making a stable contact. The protrusions may also function as a spring or biasing element for generating a clamping force on the rod elements as further described below. While the present disclosure describes and illustrates, the protrusions as being formed on the third concaved surface  24   s,  one skilled in the art will appreciate that the protrusions may be form on the first concaved surface and/or the second concaved surface in addition to or in place of the protrusions on the third concaved surface. 
         [0024]    The dimensions of the rod clip stand  10  are configured to releasably secure rod elements  12 ,  14  together. In this regard, the height h as shown in  FIG. 5  is equal to or slightly less than the sum of the diameters of rod elements  12 ,  14  for providing interference fit into the rod clip stand  10 . As such, the rod clips stand  10 , and more particularly the cradle portion  18  and the arch portion  20 , generate a clamping force that acts to hold rod elements  12 ,  14  together. The rod clip stand  10  may further include a retaining element, which is configured to engage one or both rod elements  12 ,  14  and securely couple the rod clip stand thereto. As best seen in  FIGS. 1 and 5 , the first and second cradles  18 ,  20  have a cam surface  36 ,  38  formed on an edge leading to the first and second concave surfaces  18   s,    20   s  that define a retaining element. During assembly, the rod clips stand  10  is rotated clockwise (as seen in  FIG. 5 ) so that rod element  12  engages the cam surfaces  36 ,  38  causing the rod clip stand to elastically deformed. Once the rod element  12  clears the cam surfaces  36 ,  38 , the rod clip stand  10  returns to its undeformed state and captures the rod element  12  within the cradle portion  16 . 
         [0025]    With reference now to  FIGS. 9 and 10 , the rod clip stand  10  may be a plastic part preferably fabricated using an injection molding process. The rod clip stand  10  is shown in the figured as a solid plastic part. One skilled in the art will readily recognize that the rod clip stand  10  may be molded to have certain voids or pockets to reduce weight and material necessary for its fabrication. In this regard, the rod clip stand  10  must have sufficient strength to support the rod elements  12 ,  14  and any load imparted thereon. One skilled in the art will also recognize that a plurality of the rod clip stands  10  may be molded at the same time and arranged in a chain  40  of rod clip stands  10  as shown in  FIG. 9 . Adjacent rod clip stands  10  in the chain  40  are interconnected by sprues  42  as best seen in  FIG. 10 . With continued reference to  FIG. 10 , individual chains  40  may be nested together to form a sheet  44  of rod clip stands  10 . Multiple sheets  44  of rod clip stands  10  may be readily stacked together and packaged for storage and shipping. 
         [0026]    The simple unitary design is lightweight, using about significantly less material of conventional rebar support chairs. While the number of rod clip stands  10  in a chain  40  may vary, it is presently preferred to include sixteen (16) individual rod clip stands  10  in a chain  40 . These chains  40  can be nested into a sheet  44 . Multiple sheets  44  may be stacked on top of one another to form a cube for compact storage and reduced shipping cost. For example, over 450 chains or more than 7200 rod clip stands may be nested and stacked so as to fit into a standard 2 ft×2 ft×2 ft box. One or more chains  40  can be carried on a belt so that a reinforcing ironworker or rod buster can quickly and efficiently fabricate a lattice or grid structure using these rod clip stands. 
         [0027]    In this configuration, the rod clip stand  10  can be used in a quick and efficient manner. For example, the reinforcing ironworker or rod buster may secure one to several chains  40  of rod clip stands  10  to a belt or other garment. Once a rebar grid is laid out, the rod buster simply breaks off a rod clip stand  10  and drops it down on top of rod element  14  so that it sits in the third concaved surface  24   s  of the arched portion  22 . Next, rod element  12  is held up against rod element  14  and the rod clip stand  10  is slid into engagement with rod element  12  and rotated clockwise as shown in  FIG. 5 ) so that it captures rod element  12  in the first and second concaved surfaces  18   s,    20   s  of the cradle portion  16  for securing rod elements  12 ,  14  together. So secured, the rod elements  12 ,  14  can be positioned on leg potions  30 ,  32  in a spaced relationship from a floor or other support surface. 
         [0028]    While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. In addition, one skilled in that art will appreciate that the shape and size of the embodiment may be varied to accommodate different types of rod elements. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.