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FIELD 
       [0001]    There is described a rebar support that supports rebar within concrete forms when forming concrete structures. 
       BACKGROUND 
       [0002]    There are various configurations of rebar support used when forming concrete structures. One type of rebar support is a rebar chair, A rebar chair is used to lift rebar, so it will become completely surrounded by and encased in concrete. The rebar chair is frequently made of polymer plastic. Examples of rebar chairs include: US Design Patents D444,244; D483,246; D500,668; D548,053; D548,056; D594,737; and D618,988. 
         [0003]    In some applications, engineering specifications call for the rebar to be supplemented. In such applications, the rebar is tied together by metal connectors, sometimes referred to as rebar “stirrups”. Once embedded in concrete, the metal connectors and the rebar together form an integrated reinforcement web which provides more reinforcement than rebar alone is capable of providing. 
       SUMMARY 
       [0004]    There is provided a rebar support for use in forming concrete structures, including a body formed from a single piece of an elongated metal substrate bent to define a first foot, a second foot positioned in spaced relation to the first foot, and a spanning segment that is vertically elevated, spans between the first foot and the second foot and has at least one rebar receptacle. 
         [0005]    The rebar support, as described above, is capable of functioning as a rebar chair. However, once embedded in concrete it also becomes part of an integrated reinforcement web which provides more reinforcement than is possible using rebar in combination with any of the polymer plastic rebar chairs identified above. The rebar support acts as a mechanical lock between beam and slab when engineered as a composite slab. The length of the first foot and the second foot allows for self-spacing. 
         [0006]    The actual configuration of the rebar support, such as the number of receptacles for holding rebar and their vertical and horizontal spacing can be varied. With the configuration that has been chosen for illustration and will hereinafter be described, the spanning segment includes: a central rebar receptacle of a first height centrally positioned between the first foot and the second foot, a first side rebar receptacle positioned between the first foot and the central rebar support, a second side rebar receptacle positioned between the second foot and the central rebar support. The height of the first side rebar receptacle and the second side rebar receptacle are shown as being lower than the first height of the central rebar receptacle. 
         [0007]    The rebar support, described above, can be made out of a variety of metal stock. In order to promote the flow of concrete around the support it is preferred that the body is circular in cross-section. Beneficial results have been obtained through the use of wire. 
         [0008]    In order to provide stability and resistance to tipping, it is preferred that an extremity of the first foot is oriented in a first direction and an extremity of the second foot is oriented in a second direction opposed to the first direction. It is also preferred that the central rebar receptacle, the first side rebar receptacle, and the second side rebar receptacle be defined by generally “U” shaped recesses oriented to support rebar in parallel spaced relation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    These, and other features will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to be in any way limiting, wherein: 
           [0010]      FIG. 1  is a perspective view of a rebar support. 
           [0011]      FIG. 2  is a side elevation view the rebar support of  FIG. 1 . 
           [0012]      FIG. 3  is a front elevation view the rebar support of  FIG. 1 . 
           [0013]      FIG. 4  is a bottom plan view the rebar support of  FIG. 1 . 
           [0014]      FIG. 5  is a perspective view the rebar support of  FIG. 1  positioned within a concrete form supporting rebar. 
           [0015]      FIG. 6  is a side elevation view, in section, of the rebar support positioned within a short composite slab. 
           [0016]      FIG. 7  is a side elevation view, in section of the rebar support positioned within a tall composite slab. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    A rebar support generally identified by reference numeral  10 , will now be described with reference to  FIG. 1  through  FIG. 7 . 
       Structure and Relationship of Parts: 
       [0018]    Referring to  FIG. 1 , a rebar support  10  is a body  12  formed from a single piece of wire. Body  12  includes a first foot  14 , a second foot  16  and a spanning segment  18 . First foot  14  has an extremity that is a first end  20  of wire body  12  and is oriented in a first direction  22 . Second foot  16  has an extremity that is a second end  24  of wire body  12  and is oriented in a second direction  26  which opposes first direction  22 . Spanning segment  18  spans between first foot  14  and second foot  16 . 
         [0019]    Spanning segment  18  includes central rebar receptacle  28 , a first side rebar receptacle  30  and a second side rebar receptacle  32 . Each of central rebar receptacle  28 , first side rebar receptacle  30  and second side rebar receptacle  32  are “U” shaped. Central rebar receptacle  28  is of a first height centrally positioned between first foot  14  and second foot  16 , while first side rebar receptacle  30  and second rebar receptacle  32  are of a second height lower than the first height. Referring to  FIG. 4 , first side rebar receptacle  30  is positioned between first foot  14  and central rebar support  28  and second side rebar receptacle  32  is positioned between second foot  16  and central rebar support  28 . Referring to  FIG. 3 , first side rebar receptacle  30  and second side rebar receptacle  32  may be of the same height or second side rebar receptacle  32  may be a third height which is lower than the first height and higher than the second height. 
         [0020]    Referring to  FIG. 5 , central rebar receptacle  28 , first side rebar receptacle  30  and second side rebar receptacle  32  are oriented to support rebar  34 A,  34 B and  34 C or a bundled rebar configuration in parallel spaced relation with rebar  34 A,  34 B and  34 C spaced both vertically and horizontally. 
       Operation: 
       [0021]    Referring to  FIG. 5 , multiple rebar supports  10  are placed in beam form  36  prior to pouring cement. Rebar supports  10  are placed such that central rebar receptacle  28 , first side rebar receptacle  30  and second side rebar receptacle  32  of one of rebar supports  10  are in alignment with those of the other rebar supports. First foot  14  and second foot  16  are placed in contact with bottom  38  of beam form  36  with spanning segment  18  spanning the space above first foot  14  and second foot  16 . Rebar  34  is inserted into central rebar receptacle  28  of rebar supports  10 , first side rebar receptacle  30  and second side rebar receptacle  32 . Once rebar  34  is in position, concrete can be poured into beam form  36  to create a rebar supported concrete beam-truss. Although first side rebar receptacle  30  and second side rebar receptacle  32  are shown as being at the same height, it will be understood that each of central rebar receptacle  28 , first side rebar receptacle  30  and second side rebar receptacle  32  may be at different heights which would allow for concrete blocks with rebar support in different areas. First foot  14  and second foot  16  are of a length designed to self-space which provides for shear reinforcement. 
         [0022]    Referring to  FIG. 6  and  FIG. 7 , show multiple rebar support  10  used in a composite slab to provide reinforcement. Body  12  provides support to rebar  34 A,  34 B, and  34 C. There is also an additional rebar  34 D, which rests on an angle to and on top of rebar  34 A to provide shear reinforcement. Body  12  of rebar supports  10 , together with rebar  34 A,  34 B and  34 C act as a mechanical lock between the beam and the concrete slab of the composite slab. 
         [0023]    It will be apparent to a person skilled in the art that instead of using wire for rebar support  10 , one could also make rebar support out of rebar or other elongated metal stock material. 
         [0024]    In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements. 
         [0025]    The following claims are to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, and what can be obviously substituted. Those skilled in the art will appreciate that various adaptations and modifications of the described embodiments can be configured without departing from the scope of the claims. The illustrated embodiments have been set forth only as examples and should not be taken as limiting the invention. It is to be understood that, within the scope of the following claims, the invention may be practiced other than as specifically illustrated and described.

Summary:
A rebar support for use in forming concrete structures, includes a body formed from a single piece of an elongated metal substrate bent to define a first foot, a second foot positioned in spaced relation to the first foot, and a spanning segment that is vertically elevated, spans between the first foot and the second foot and has at least one rebar receptacle.