Patent Publication Number: US-2005133684-A1

Title: Holder for rebar

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention provides a device for supporting vertical steel rebar of various diameters during the pouring of a concrete structure.  
      2. Description of the Prior Art  
      In typical construction projects which require concrete structures, such as foundations, vertical extending steel rebar is necessary to strengthen the structure.  
      In order to hold the rebar in position during the pouring of the concrete, the prior art typically utilized steel tie wires connecting the rebar to an underlying wood frame member. In essence, the tie wire is coupled to the rebar at one end and the wood frame at the other. After the concrete sets, the wood frame is removed from the adjacent concrete structure. Although the use of tie wires provides a simple technique for positioning the rebar, it requires a person to hold the rebar during the tying operation. In addition, the rebar often does not maintain a proper vertical orientation during the concrete pouring stage. Finally, wire cutters are needed to cut the tie wire in order to remove the wood frame after the concrete sets.  
      An improved vertical rebar positioning device is a hook and clamp type device that had once been manufactured by Precision Builders, Redding, Calif. The hook portion of this device fits about the rebar, the clamp portion being secured to the wood frame. Although providing advantages over the commonly used tie wires, it has serious disadvantages in that it is costly and difficult to remove the wood frame member after the concrete sets.  
      U.S. Pat. No. 5,688,428, issued on Nov. 18, 1997 to the applicant, discloses an improved device for positioning vertical steel rebar which is less expensive than those available in the prior art and wherein the installation time required for the vertical steel rebar is reduced, thus reducing labor costs. The device disclosed in the &#39;428 patent has found wide commercial acceptance and has a plurality of different sized holders for holding steel rebar of various external diameters. A device which utilizes a single holder issued as U.S. Pat. No. 6,017,014 on Jan. 25, 2000 to the applicant.  
      Although the holder disclosed in the &#39;428 patent provides significant advantages as noted hereinabove, circumstances may arise when more than a single rebar of the same diameter may be necessary to be used at the same time. The multiple holder disclosed in the &#39;428 patent is limited to using a single rebar of the same diameter at the same time; the device disclosed in the &#39;014 patent, as noted hereinabove, utilizes a single rebar holder.  
      What is thus desired is to provide an improved steel rebar holder device wherein at least two vertical rebars having the same outside diameter can be held, or supported, at the same time.  
     SUMMARY OF THE INVENTION  
      The present invention provides a member having first and second vertically extending leg portions, and a base member connecting one end of each leg member, a wood frame member for the concrete structure being positioned in the channel formed between the first and second leg portions. First and second cup shaped members have first and second internal diameters, respectively, are formed along the outside surface of said first leg portion, third and fourth of cup shaped members having third and fourth internal diameters respectively, being formed along the outside surface of said second leg portion, said first and third internal diameters being equal and said second and fourth internal diameters being equal. Vertical steel rebars of the same outside diameter are positioned and held in said first and third cup shaped members. Holes are formed in the base member to receive fasteners which are used to secure the member to the underlying wood frame member. Protrusions are provided on the bottom surface of the base member to provide a space between the surface and the adjacent top surface of the wood frame member to enable the device to be removed after the concrete sets.  
      The present invention thus provides a relatively inexpensive vertical steel rebar holder device which has the capability of supporting at least two rebars of the same diameter at the same time and wherein the device can be easily removed after the concrete is poured and sets. 
    
    
     DESCRIPTION OF THE DRAWINGS  
      For a better understanding of the present invention as well as other objects and further features thereof, reference is made to the following description which is to be read in conjunction with the accompanying drawing therein:  
       FIG. 1  is a perspective view of the device of the present invention;  
       FIG. 2  is a top plan view of the device shown in  FIG. 1 ;  
       FIG. 3  is a cross-sectional view along line  3 - 3  of  FIG. 2 ; and  
       FIG. 4  is a cross-sectional view along line  4 - 4  of  FIG. 3 .  
    
    
     DESCRIPTION OF THE INVENTION  
      Referring now to  FIGS. 1-4 , a vertical steel rebar holding device  10  of the present invention is illustrated. Device  10 , preferably made of plastic, comprises a U-shaped member having leg portions  12  and  14  joined by base member  16  and cup shaped members  20  and  22  integral with the outside surface  15  of leg portion  12  and cup shaped members  24  and  26  integral with the outside surface  17  of leg portion  14  as illustrated. The cupped shaped members  20 ,  22 ,  24  and  26  are essentially cylindrical in shape and have an extended longitudinal opening, or, slot formed along the entire length thereof as illustrated. The internal diameter of the shaped members are of a predetermined size and selected to correspond to the outside diameter of steel rebar having a specific diameter. In accordance with the teachings of the present invention members  20  and  24  have the same internal diameter and members  22  and  26  have the same internal diameter. In the example illustrated, cup shaped member  20  and  24  have an internal diameter of approximately 0.5 inches and are sized to frictionally engage the vertical steel rebar  30  and hold the rebar in place during the concrete pouring operation. Cup shaped members  22  and  26  in the example illustrated, have a internal diameter of approximately 0.75 inches and are sized to frictionally engage vertical rebar inserted therein. It should be noted that although the rebar is the preferred structural member to be inserted into member  20 , an anchor bolt can also be utilized if necessary. The length of device  10 , along its longitudinal dimension, is variable, typically in range from about 4 inches to about 6 inches and is selected to enable the steel rebar to be utilized for a particular project. A hole, or aperture,  40  is formed in base member  16  and a fastener, such as a nail, is positioned therethrough to secure device  10  to frame member  32 .  
      It should be noted that although the preferred embodiment illustrates cupped shaped members having different internal diameters formed along the outside surface of the same leg portion, the device can be configured such that the holders have the same internal diameter along the surface of either the first or second leg portion.  
      In operation, after the wood framing is constructed, device  10  is positioned over the top edge thereof in the manner shown in  FIGS. 2-4 . Fastener  42  is then inserted through hole  40  into the surface  31  of frame member  32 . Steel rebar  30  is then positioned into members  20  and  24  and thereafter the concrete is poured. It should be noted that the height of device  10  is selected, in conjunction with the height of wood frame member  32 , so that the level of the concrete is below the bottom surface of the cup shaped members. In essence, the device  10  is not embedded in the concrete after the concrete sets. After the concrete sets, device  10  is removed from frame member  32  by first removing fastener  42  and then using the claw portion of a hammer to remove device  10  and then hitting the side of wooden member  32  so that the wooden member slides free from the adjacent set concrete. Alternatively, device  10  can be hit in the direction facing the open portion of the cup members, thus causing the device to slide off frame member  32 .  
      Triangular shaped see-through apertures  70  are formed in base portion  16  enabling a user to look for a marking formed in the upper surface of wood frame member  32  and accurately position device  10 . A pair of protrusions  76  and  78  are formed in the lower surface  80  of base member  16  to provide a space  82  between surface  80  and the adjacent surface of frame member  32 .  
      Device  10  is preferably made of plastic and molded in a manner such that base member  16 , leg portions  12  and  14 , holder members  20 ,  22 ,  24  and  26  and protrusions  76  and  78  are integral.  
      While the invention has been described with reference to its preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its essential teachings.